Search This Blog

Tuesday, October 23, 2018

The American Economy Is Rigged

And what we can do about it.
By |
The American Economy Is Rigged
Credit: Andrea Ucini
Americans are used to thinking that their nation is special. In many ways, it is: the U.S. has by far the most Nobel Prize winners, the largest defense expenditures (almost equal to the next 10 or so countries put together) and the most billionaires (twice as many as China, the closest competitor). But some examples of American Exceptionalism should not make us proud. By most accounts, the U.S. has the highest level of economic inequality among developed countries. It has the world's greatest per capita health expenditures yet the lowest life expectancy among comparable countries. It is also one of a few developed countries jostling for the dubious distinction of having the lowest measures of equality of opportunity.

The notion of the American Dream—that, unlike old Europe, we are a land of opportunity—is part of our essence. Yet the numbers say otherwise. The life prospects of a young American depend more on the income and education of his or her parents than in almost any other advanced country. When poor-boy-makes-good anecdotes get passed around in the media, that is precisely because such stories are so rare.

Things appear to be getting worse, partly as a result of forces, such as technology and globalization, that seem beyond our control, but most disturbingly because of those within our command. It is not the laws of nature that have led to this dire situation: it is the laws of humankind. Markets do not exist in a vacuum: they are shaped by rules and regulations, which can be designed to favor one group over another. President Donald Trump was right in saying that the system is rigged—by those in the inherited plutocracy of which he himself is a member. And he is making it much, much worse.

America has long outdone others in its level of inequality, but in the past 40 years it has reached new heights. Whereas the income share of the top 0.1 percent has more than quadrupled and that of the top 1 percent has almost doubled, that of the bottom 90 percent has declined. Wages at the bottom, adjusted for inflation, are about the same as they were some 60 years ago! In fact, for those with a high school education or less, incomes have fallen over recent decades. Males have been particularly hard hit, as the U.S. has moved away from manufacturing industries into an economy based on services.

Deaths of Despair

Wealth is even less equally distributed, with just three Americans having as much as the bottom 50 percent—testimony to how much money there is at the top and how little there is at the bottom. Families in the bottom 50 percent hardly have the cash reserves to meet an emergency. Newspapers are replete with stories of those for whom the breakdown of a car or an illness starts a downward spiral from which they never recover.

In significant part because of high inequality [see “The Health-Wealth Gap,” by Robert M. Sapolsky], U.S. life expectancy, exceptionally low to begin with, is experiencing sustained declines. This in spite of the marvels of medical science, many advances of which occur right here in America and which are made readily available to the rich. Economist Ann Case and 2015 Nobel laureate in economics Angus Deaton describe one of the main causes of rising morbidity—the increase in alcoholism, drug overdoses and suicides—as “deaths of despair” by those who have given up hope.
Credit: Jen Christiansen; Sources: “The Fading American Dream: Trends in Absolute Income Mobility Since 1940,” by Raj Chetty et al., in Science, Vol. 356; April 28, 2017 (child-parent wealth comparison); World Inequality database (90% versus 1% wealth trend data)
Defenders of America's inequality have a pat explanation. They refer to the workings of a competitive market, where the laws of supply and demand determine wages, prices and even interest rates—a mechanical system, much like that describing the physical universe. Those with scarce assets or skills are amply rewarded, they argue, because of the larger contributions they make to the economy. What they get merely represents what they have contributed. Often they take out less than they contributed, so what is left over for the rest is that much more.

This fictional narrative may at one time have assuaged the guilt of those at the top and persuaded everyone else to accept this sorry state of affairs. Perhaps the defining moment exposing the lie was the 2008 financial crisis, when the bankers who brought the global economy to the brink of ruin with predatory lending, market manipulation and various other antisocial practices walked away with millions of dollars in bonuses just as millions of Americans lost their jobs and homes and tens of millions more worldwide suffered on their account. Virtually none of these bankers were ever held to account for their misdeeds.

I became aware of the fantastical nature of this narrative as a schoolboy, when I thought of the wealth of the plantation owners, built on the backs of slaves. At the time of the Civil War, the market value of the slaves in the South was approximately half of the region's total wealth, including the value of the land and the physical capital—the factories and equipment. The wealth of at least this part of this nation was not based on industry, innovation and commerce but rather on exploitation. Today we have replaced this open exploitation with more insidious forms, which have intensified since the Reagan-Thatcher revolution of the 1980s. This exploitation, I will argue, is largely to blame for the escalating inequality in the U.S.

After the New Deal of the 1930s, American inequality went into decline. By the 1950s inequality had receded to such an extent that another Nobel laureate in economics, Simon Kuznets, formulated what came to be called Kuznets's law. In the early stages of development, as some parts of a country seize new opportunities, inequalities grow, he postulated; in the later stages, they shrink. The theory long fit the data—but then, around the early 1980s, the trend abruptly reversed.

Explaining Inequality

Economists have put forward a range of explanations for why inequality has in fact been increasing in many developed countries. Some argue that advances in technology have spurred the demand for skilled labor relative to unskilled labor, thereby depressing the wages of the latter. Yet that alone cannot explain why even skilled labor has done so poorly over the past two decades, why average wages have done so badly and why matters are so much worse in the U.S. than in other developed nations. Changes in technology are global and should affect all advanced economies in the same way. Other economists blame globalization itself, which has weakened the power of workers. Firms can and do move abroad unless demands for higher wages are curtailed. But again, globalization has been integral to all advanced economies. Why is its impact so much worse in the U.S.?

The shift from a manufacturing to a service-based economy is partly to blame. At its extreme—a firm of one person—the service economy is a winner-takes-all system. A movie star makes millions, for example, whereas most actors make a pittance. Overall, wages are likely to be far more widely dispersed in a service economy than in one based on manufacturing, so the transition contributes to greater inequality. This fact does not explain, however, why the average wage has not improved for decades. Moreover, the shift to the service sector is happening in most other advanced countries: Why are matters so much worse in the U.S.?

Again, because services are often provided locally, firms have more market power: the ability to raise prices above what would prevail in a competitive market. A small town in rural America may have only one authorized Toyota repair shop, which virtually every Toyota owner is forced to patronize. The providers of these local services can raise prices over costs, increasing their profits and the share of income going to owners and managers. This, too, increases inequality. But again, why is U.S. inequality practically unique?

In his celebrated 2013 treatise Capital in the Twenty-First Century, French economist Thomas Piketty shifts the gaze to capitalists. He suggests that the few who own much of a country's capital save so much that, given the stable and high return to capital (relative to the growth rate of the economy), their share of the national income has been increasing. His theory has, however, been questioned on many grounds. For instance, the savings rate of even the rich in the U.S. is so low, compared with the rich in other countries, that the increase in inequality should be lower here, not greater.

An alternative theory is far more consonant with the facts. Since the mid-1970s the rules of the economic game have been rewritten, both globally and nationally, in ways that advantage the rich and disadvantage the rest. And they have been rewritten further in this perverse direction in the U.S. than in other developed countries—even though the rules in the U.S. were already less favorable to workers. From this perspective, increasing inequality is a matter of choice: a consequence of our policies, laws and regulations.

In the U.S., the market power of large corporations, which was greater than in most other advanced countries to begin with, has increased even more than elsewhere. On the other hand, the market power of workers, which started out less than in most other advanced countries, has fallen further than elsewhere. This is not only because of the shift to a service-sector economy—it is because of the rigged rules of the game, rules set in a political system that is itself rigged through gerrymandering, voter suppression and the influence of money. A vicious spiral has formed: economic inequality translates into political inequality, which leads to rules that favor the wealthy, which in turn reinforces economic inequality.

Feedback Loop

Political scientists have documented the ways in which money influences politics in certain political systems, converting higher economic inequality into greater political inequality. Political inequality, in its turn, gives rise to more economic inequality as the rich use their political power to shape the rules of the game in ways that favor them—for instance, by softening antitrust laws and weakening unions. Using mathematical models, economists such as myself have shown that this two-way feedback loop between money and regulations leads to at least two stable points. If an economy starts out with lower inequality, the political system generates rules that sustain it, leading to one equilibrium situation. The American system is the other equilibrium—and will continue to be unless there is a democratic political awakening.

An account of how the rules have been shaped must begin with antitrust laws, first enacted 128 years ago in the U.S. to prevent the agglomeration of market power. Their enforcement has weakened—at a time when, if anything, the laws themselves should have been strengthened. Technological changes have concentrated market power in the hands of a few global players, in part because of so-called network effects: you are far more likely to join a particular social network or use a certain word processor if everyone you know is already using it. Once established, a firm such as Facebook or Microsoft is hard to dislodge. Moreover, fixed costs, such as that of developing a piece of software, have increased as compared with marginal costs—that of duplicating the software. A new entrant has to bear all these fixed costs up front, and if it does enter, the rich incumbent can respond by lowering prices drastically. The cost of making an additional e-book or photo-editing program is essentially zero.

In short, entry is hard and risky, which gives established firms with deep war chests enormous power to crush competitors and ultimately raise prices. Making matters worse, U.S. firms have been innovative not only in the products they make but in thinking of ways to extend and amplify their market power. The European Commission has imposed fines of billions of dollars on Microsoft and Google and ordered them to stop their anticompetitive practices (such as Google privileging its own comparison shopping service). In the U.S., we have done too little to control concentrations of market power, so it is not a surprise that it has increased in many sectors.
Credit: Jen Christiansen; Sources: Economic Report of the President. January 2017; World Inequality database
Rigged rules also explain why the impact of globalization may have been worse in the U.S. A concerted attack on unions has almost halved the fraction of unionized workers in the nation, to about 11 percent. (In Scandinavia, it is roughly 70 percent.) Weaker unions provide workers less protection against the efforts of firms to drive down wages or worsen working conditions. Moreover, U.S. investment treaties such as the North Atlantic Free Trade Agreement—treaties that were sold as a way of preventing foreign countries from discriminating against American firms—also protect investors against a tightening of environmental and health regulations abroad. For instance, they enable corporations to sue nations in private international arbitration panels for passing laws that protect citizens and the environment but threaten the multinational company's bottom line. Firms like these provisions, which enhance the credibility of a company's threat to move abroad if workers do not temper their demands. In short, these investment agreements weaken U.S. workers' bargaining power even further.

Liberated Finance

Many other changes to our norms, laws, rules and regulations have contributed to inequality. Weak corporate governance laws have allowed chief executives in the U.S. to compensate themselves 361 times more than the average worker, far more than in other developed countries. Financial liberalization—the stripping away of regulations designed to prevent the financial sector from imposing harms, such as the 2008 economic crisis, on the rest of society—has enabled the finance industry to grow in size and profitability and has increased its opportunities to exploit everyone else. Banks routinely indulge in practices that are legal but should not be, such as imposing usurious interest rates on borrowers or exorbitant fees on merchants for credit and debit cards and creating securities that are designed to fail. They also frequently do things that are illegal, including market manipulation and insider trading. In all of this, the financial sector has moved money away from ordinary Americans to rich bankers and the banks' shareholders. This redistribution of wealth is an important contributor to American inequality.

Other means of so-called rent extraction—the withdrawal of income from the national pie that is incommensurate with societal contribution—abound. For example, a legal provision enacted in 2003 prohibited the government from negotiating drug prices for Medicare—a gift of some $50 billion a year or more to the pharmaceutical industry. Special favors, such as extractive industries' obtaining public resources such as oil at below fair-market value or banks' getting funds from the Federal Reserve at near-zero interest rates (which they relend at high interest rates), also amount to rent extraction. Further exacerbating inequality is favorable tax treatment for the rich. In the U.S., those at the top pay a smaller fraction of their income in taxes than those who are much poorer—a form of largesse that the Trump administration has just worsened with the 2017 tax bill.

Some economists have argued that we can lessen inequality only by giving up on growth and efficiency. But recent research, such as work done by Jonathan Ostry and others at the International Monetary Fund, suggests that economies with greater equality perform better, with higher growth, better average standards of living and greater stability. Inequality in the extremes observed in the U.S. and in the manner generated there actually damages the economy. The exploitation of market power and the variety of other distortions I have described, for instance, makes markets less efficient, leading to underproduction of valuable goods such as basic research and overproduction of others, such as exploitative financial products.
Credit: Jen Christiansen; Sources: World Inequality Report 2018. World Inequality Lab, 2017; Branko Milanovic
Moreover, because the rich typically spend a smaller fraction of their income on consumption than the poor, total or “aggregate” demand in countries with higher inequality is weaker. Societies could make up for this gap by increasing government spending—on infrastructure, education and health, for instance, all of which are investments necessary for long-term growth. But the politics of unequal societies typically puts the burden on monetary policy: interest rates are lowered to stimulate spending. Artificially low interest rates, especially if coupled with inadequate financial market regulation, often give rise to bubbles, which is what happened with the 2008 housing crisis.
It is no surprise that, on average, people living in unequal societies have less equality of opportunity: those at the bottom never get the education that would enable them to live up to their potential. This fact, in turn, exacerbates inequality while wasting the country's most valuable resource: Americans themselves.

Restoring Justice

Morale is lower in unequal societies, especially when inequality is seen as unjust, and the feeling of being used or cheated leads to lower productivity. When those who run gambling casinos or bankers suffering from moral turpitude make a zillion times more than the scientists and inventors who brought us lasers, transistors and an understanding of DNA, it is clear that something is wrong. Then again, the children of the rich come to think of themselves as a class apart, entitled to their good fortune, and accordingly more likely to break the rules necessary for making society function. All of this contributes to a breakdown of trust, with its attendant impact on social cohesion and economic performance.

There is no magic bullet to remedy a problem as deep-rooted as America's inequality. Its origins are largely political, so it is hard to imagine meaningful change without a concerted effort to take money out of politics—through, for instance, campaign finance reform. Blocking the revolving doors by which regulators and other government officials come from and return to the same industries they regulate and work with is also essential.
Credit: Jen Christiansen; Sources: Raising America’s Pay: Why It’s Our Central Economic Policy Challenge, by Josh Bivens et al. Economic Policy Institute, June 4, 2014; The State of Working America, by Lawrence Mishel, Josh Bivens, Elise Gould and Heidi Shierholz. 12th Edition. ILR Press, 2012
Beyond that, we need more progressive taxation and high-quality federally funded public education, including affordable access to universities for all, no ruinous loans required. We need modern competition laws to deal with the problems posed by 21st-century market power and stronger enforcement of the laws we do have. We need labor laws that protect workers and their rights to unionize. We need corporate governance laws that curb exorbitant salaries bestowed on chief executives, and we need stronger financial regulations that will prevent banks from engaging in the exploitative practices that have become their hallmark. We need better enforcement of antidiscrimination laws: it is unconscionable that women and minorities get paid a mere fraction of what their white male counterparts receive. We also need more sensible inheritance laws that will reduce the intergenerational transmission of advantage and disadvantage.

The basic perquisites of a middle-class life, including a secure old age, are no longer attainable for most Americans. We need to guarantee access to health care. We need to strengthen and reform retirement programs, which have put an increasing burden of risk management on workers (who are expected to manage their portfolios to guard simultaneously against the risks of inflation and market collapse) and opened them up to exploitation by our financial sector (which sells them products designed to maximize bank fees rather than retirement security). Our mortgage system was our Achilles' heel, and we have not really fixed it. With such a large fraction of Americans living in cities, we have to have urban housing policies that ensure affordable housing for all.

It is a long agenda—but a doable one. When skeptics say it is nice but not affordable, I reply: We cannot afford to not do these things. We are already paying a high price for inequality, but it is just a down payment on what we will have to pay if we do not do something—and quickly. It is not just our economy that is at stake; we are risking our democracy.

As more of our citizens come to understand why the fruits of economic progress have been so unequally shared, there is a real danger that they will become open to a demagogue blaming the country's problems on others and making false promises of rectifying “a rigged system.” We are already experiencing a foretaste of what might happen. It could get much worse.

This article was originally published with the title "A Rigged Economy"

MORE TO EXPLORE

The Price of Inequality: How Today's Divided Society Endangers Our Future. Joseph E. Stiglitz. W. W. Norton, 2012.

The Great Divide: Unequal Societies and What We Can Do about Them. Joseph E. Stiglitz. W. W. Norton, 2015.

Rewriting the Rules of the American Economy: An Agenda for Growth and Shared Prosperity. Joseph E. Stiglitz. W. W. Norton, 2015.

Globalization and Its Discontents Revisited: Anti-globalization in the Era of Trump. Joseph E. Stiglitz. W. W. Norton, 2017.

Data analysis

From Wikipedia, the free encyclopedia

Data analysis is a process of inspecting, cleansing, transforming, and modeling data with the goal of discovering useful information, informing conclusions, and supporting decision-making. Data analysis has multiple facets and approaches, encompassing diverse techniques under a variety of names, while being used in different business, science, and social science domains.

Data mining is a particular data analysis technique that focuses on modeling and knowledge discovery for predictive rather than purely descriptive purposes, while business intelligence covers data analysis that relies heavily on aggregation, focusing mainly on business information. In statistical applications, data analysis can be divided into descriptive statistics, exploratory data analysis (EDA), and confirmatory data analysis (CDA). EDA focuses on discovering new features in the data while CDA focuses on confirming or falsifying existing hypotheses. Predictive analytics focuses on application of statistical models for predictive forecasting or classification, while text analytics applies statistical, linguistic, and structural techniques to extract and classify information from textual sources, a species of unstructured data. All of the above are varieties of data analysis.

Data integration is a precursor to data analysis, and data analysis is closely linked to data visualization and data dissemination. The term data analysis is sometimes used as a synonym for data modeling.

The process of data analysis

Data science process flowchart from "Doing Data Science", Cathy O'Neil and Rachel Schutt, 2013

Analysis refers to breaking a whole into its separate components for individual examination. Data analysis is a process for obtaining raw data and converting it into information useful for decision-making by users. Data is collected and analyzed to answer questions, test hypotheses or disprove theories.

Statistician John Tukey defined data analysis in 1961 as: "Procedures for analyzing data, techniques for interpreting the results of such procedures, ways of planning the gathering of data to make its analysis easier, more precise or more accurate, and all the machinery and results of (mathematical) statistics which apply to analyzing data."

There are several phases that can be distinguished, described below. The phases are iterative, in that feedback from later phases may result in additional work in earlier phases.

Data requirements

The data is necessary as inputs to the analysis, which is specified based upon the requirements of those directing the analysis or customers (who will use the finished product of the analysis). The general type of entity upon which the data will be collected is referred to as an experimental unit (e.g., a person or population of people). Specific variables regarding a population (e.g., age and income) may be specified and obtained. Data may be numerical or categorical (i.e., a text label for numbers).

Data collection

Data is collected from a variety of sources. The requirements may be communicated by analysts to custodians of the data, such as information technology personnel within an organization. The data may also be collected from sensors in the environment, such as traffic cameras, satellites, recording devices, etc. It may also be obtained through interviews, downloads from online sources, or reading documentation.

Data processing

The phases of the intelligence cycle used to convert raw information into actionable intelligence or knowledge are conceptually similar to the phases in data analysis.

Data initially obtained must be processed or organised for analysis. For instance, these may involve placing data into rows and columns in a table format (i.e., structured data) for further analysis, such as within a spreadsheet or statistical software.

Data cleaning

Once processed and organised, the data may be incomplete, contain duplicates, or contain errors. The need for data cleaning will arise from problems in the way that data is entered and stored. Data cleaning is the process of preventing and correcting these errors. Common tasks include record matching, identifying inaccuracy of data, overall quality of existing data, deduplication, and column segmentation. Such data problems can also be identified through a variety of analytical techniques. For example, with financial information, the totals for particular variables may be compared against separately published numbers believed to be reliable. Unusual amounts above or below pre-determined thresholds may also be reviewed. There are several types of data cleaning that depend on the type of data such as phone numbers, email addresses, employers etc. Quantitative data methods for outlier detection can be used to get rid of likely incorrectly entered data. Textual data spell checkers can be used to lessen the amount of mistyped words, but it is harder to tell if the words themselves are correct.

Exploratory data analysis

Once the data is cleaned, it can be analyzed. Analysts may apply a variety of techniques referred to as exploratory data analysis to begin understanding the messages contained in the data. The process of exploration may result in additional data cleaning or additional requests for data, so these activities may be iterative in nature. Descriptive statistics, such as the average or median, may be generated to help understand the data. Data visualization may also be used to examine the data in graphical format, to obtain additional insight regarding the messages within the data.

Modeling and algorithms

Mathematical formulas or models called algorithms may be applied to the data to identify relationships among the variables, such as correlation or causation. In general terms, models may be developed to evaluate a particular variable in the data based on other variable(s) in the data, with some residual error depending on model accuracy (i.e., Data = Model + Error).

Inferential statistics includes techniques to measure relationships between particular variables. For example, regression analysis may be used to model whether a change in advertising (independent variable X) explains the variation in sales (dependent variable Y). In mathematical terms, Y (sales) is a function of X (advertising). It may be described as Y = aX + b + error, where the model is designed such that a and b minimize the error when the model predicts Y for a given range of values of X. Analysts may attempt to build models that are descriptive of the data to simplify analysis and communicate results.

Data product

A data product is a computer application that takes data inputs and generates outputs, feeding them back into the environment. It may be based on a model or algorithm. An example is an application that analyzes data about customer purchasing history and recommends other purchases the customer might enjoy.

Communication

Data visualization to understand the results of a data analysis.

Once the data is analyzed, it may be reported in many formats to the users of the analysis to support their requirements. The users may have feedback, which results in additional analysis. As such, much of the analytical cycle is iterative.

When determining how to communicate the results, the analyst may consider data visualization techniques to help clearly and efficiently communicate the message to the audience. Data visualization uses information displays (such as tables and charts) to help communicate key messages contained in the data. Tables are helpful to a user who might lookup specific numbers, while charts (e.g., bar charts or line charts) may help explain the quantitative messages contained in the data.

Quantitative messages

A time series illustrated with a line chart demonstrating trends in U.S. federal spending and revenue over time.
 
A scatterplot illustrating correlation between two variables (inflation and unemployment) measured at points in time.

Stephen Few described eight types of quantitative messages that users may attempt to understand or communicate from a set of data and the associated graphs used to help communicate the message. Customers specifying requirements and analysts performing the data analysis may consider these messages during the course of the process.
  1. Time-series: A single variable is captured over a period of time, such as the unemployment rate over a 10-year period. A line chart may be used to demonstrate the trend;
  2. Ranking: Categorical subdivisions are ranked in ascending or descending order, such as a ranking of sales performance (the measure) by sales persons (the category, with each sales person a categorical subdivision) during a single period. A bar chart may be used to show the comparison across the sales persons;
  3. Part-to-whole: Categorical subdivisions are measured as a ratio to the whole (i.e., a percentage out of 100%). A pie chart or bar chart can show the comparison of ratios, such as the market share represented by competitors in a market;
  4. Deviation: Categorical subdivisions are compared against a reference, such as a comparison of actual vs. budget expenses for several departments of a business for a given time period. A bar chart can show comparison of the actual versus the reference amount;
  5. Frequency distribution: Shows the number of observations of a particular variable for given interval, such as the number of years in which the stock market return is between intervals such as 0–10%, 11–20%, etc. A histogram, a type of bar chart, may be used for this analysis;
  6. Correlation: Comparison between observations represented by two variables (X,Y) to determine if they tend to move in the same or opposite directions. For example, plotting unemployment (X) and inflation (Y) for a sample of months. A scatter plot is typically used for this message;
  7. Nominal comparison: Comparing categorical subdivisions in no particular order, such as the sales volume by product code. A bar chart may be used for this comparison;
  8. Geographic or geospatial: Comparison of a variable across a map or layout, such as the unemployment rate by state or the number of persons on the various floors of a building. A cartogram is a typical graphic used.

Techniques for analyzing quantitative data

Author Jonathan Koomey has recommended a series of best practices for understanding quantitative data. These include:
  • Check raw data for anomalies prior to performing your analysis;
  • Re-perform important calculations, such as verifying columns of data that are formula driven;
  • Confirm main totals are the sum of subtotals;
  • Check relationships between numbers that should be related in a predictable way, such as ratios over time;
  • Normalize numbers to make comparisons easier, such as analyzing amounts per person or relative to GDP or as an index value relative to a base year;
  • Break problems into component parts by analyzing factors that led to the results, such as DuPont analysis of return on equity.
For the variables under examination, analysts typically obtain descriptive statistics for them, such as the mean (average), median, and standard deviation. They may also analyze the distribution of the key variables to see how the individual values cluster around the mean.

An illustration of the MECE principle used for data analysis.

The consultants at McKinsey and Company named a technique for breaking a quantitative problem down into its component parts called the MECE principle. Each layer can be broken down into its components; each of the sub-components must be mutually exclusive of each other and collectively add up to the layer above them. The relationship is referred to as "Mutually Exclusive and Collectively Exhaustive" or MECE. For example, profit by definition can be broken down into total revenue and total cost. In turn, total revenue can be analyzed by its components, such as revenue of divisions A, B, and C (which are mutually exclusive of each other) and should add to the total revenue (collectively exhaustive).

Analysts may use robust statistical measurements to solve certain analytical problems. Hypothesis testing is used when a particular hypothesis about the true state of affairs is made by the analyst and data is gathered to determine whether that state of affairs is true or false. For example, the hypothesis might be that "Unemployment has no effect on inflation", which relates to an economics concept called the Phillips Curve. Hypothesis testing involves considering the likelihood of Type I and type II errors, which relate to whether the data supports accepting or rejecting the hypothesis.

Regression analysis may be used when the analyst is trying to determine the extent to which independent variable X affects dependent variable Y (e.g., "To what extent do changes in the unemployment rate (X) affect the inflation rate (Y)?"). This is an attempt to model or fit an equation line or curve to the data, such that Y is a function of X.

Necessary condition analysis (NCA) may be used when the analyst is trying to determine the extent to which independent variable X allows variable Y (e.g., "To what extent is a certain unemployment rate (X) necessary for a certain inflation rate (Y)?"). Whereas (multiple) regression analysis uses additive logic where each X-variable can produce the outcome and the X's can compensate for each other (they are sufficient but not necessary), necessary condition analysis (NCA) uses necessity logic, where one or more X-variables allow the outcome to exist, but may not produce it (they are necessary but not sufficient). Each single necessary condition must be present and compensation is not possible.

Analytical activities of data users

Users may have particular data points of interest within a data set, as opposed to general messaging outlined above. Such low-level user analytic activities are presented in the following table. The taxonomy can also be organized by three poles of activities: retrieving values, finding data points, and arranging data points.

# Task General
Description
Pro Forma
Abstract
Examples
1 Retrieve Value Given a set of specific cases, find attributes of those cases. What are the values of attributes {X, Y, Z, ...} in the data cases {A, B, C, ...}? - What is the mileage per gallon of the Ford Mondeo? - How long is the movie Gone with the Wind?
2 Filter Given some concrete conditions on attribute values, find data cases satisfying those conditions. Which data cases satisfy conditions {A, B, C...}? - What Kellogg's cereals have high fiber? - What comedies have won awards?
- Which funds underperformed the SP-500?
3 Compute Derived Value Given a set of data cases, compute an aggregate numeric representation of those data cases. What is the value of aggregation function F over a given set S of data cases? - What is the average calorie content of Post cereals? - What is the gross income of all stores combined?
- How many manufacturers of cars are there?
4 Find Extremum Find data cases possessing an extreme value of an attribute over its range within the data set. What are the top/bottom N data cases with respect to attribute A? - What is the car with the highest MPG? - What director/film has won the most awards?
- What Marvel Studios film has the most recent release date?
5 Sort Given a set of data cases, rank them according to some ordinal metric. What is the sorted order of a set S of data cases according to their value of attribute A? - Order the cars by weight. - Rank the cereals by calories.
6 Determine Range Given a set of data cases and an attribute of interest, find the span of values within the set. What is the range of values of attribute A in a set S of data cases? - What is the range of film lengths? - What is the range of car horsepowers?
- What actresses are in the data set?
7 Characterize Distribution Given a set of data cases and a quantitative attribute of interest, characterize the distribution of that attribute’s values over the set. What is the distribution of values of attribute A in a set S of data cases? - What is the distribution of carbohydrates in cereals? - What is the age distribution of shoppers?
8 Find Anomalies Identify any anomalies within a given set of data cases with respect to a given relationship or expectation, e.g. statistical outliers. Which data cases in a set S of data cases have unexpected/exceptional values? - Are there exceptions to the relationship between horsepower and acceleration? - Are there any outliers in protein?
9 Cluster Given a set of data cases, find clusters of similar attribute values. Which data cases in a set S of data cases are similar in value for attributes {X, Y, Z, ...}? - Are there groups of cereals w/ similar fat/calories/sugar? - Is there a cluster of typical film lengths?
10 Correlate Given a set of data cases and two attributes, determine useful relationships between the values of those attributes. What is the correlation between attributes X and Y over a given set S of data cases? - Is there a correlation between carbohydrates and fat? - Is there a correlation between country of origin and MPG?
- Do different genders have a preferred payment method?
- Is there a trend of increasing film length over the years?
11 Contextualization Given a set of data cases, find contextual relevancy of the data to the users. Which data cases in a set S of data cases are relevant to the current users' context? - Are there groups of restaurants that have foods based on my current caloric intake?

Barriers to effective analysis

Barriers to effective analysis may exist among the analysts performing the data analysis or among the audience. Distinguishing fact from opinion, cognitive biases, and innumeracy are all challenges to sound data analysis.

Confusing fact and opinion

You are entitled to your own opinion, but you are not entitled to your own facts.
 
Daniel Patrick Moynihan

Effective analysis requires obtaining relevant facts to answer questions, support a conclusion or formal opinion, or test hypotheses. Facts by definition are irrefutable, meaning that any person involved in the analysis should be able to agree upon them. For example, in August 2010, the Congressional Budget Office (CBO) estimated that extending the Bush tax cuts of 2001 and 2003 for the 2011–2020 time period would add approximately $3.3 trillion to the national debt. Everyone should be able to agree that indeed this is what CBO reported; they can all examine the report. This makes it a fact. Whether persons agree or disagree with the CBO is their own opinion.

As another example, the auditor of a public company must arrive at a formal opinion on whether financial statements of publicly traded corporations are "fairly stated, in all material respects." This requires extensive analysis of factual data and evidence to support their opinion. When making the leap from facts to opinions, there is always the possibility that the opinion is erroneous.

Cognitive biases

There are a variety of cognitive biases that can adversely affect analysis. For example, confirmation bias is the tendency to search for or interpret information in a way that confirms one's preconceptions. In addition, individuals may discredit information that does not support their views.

Analysts may be trained specifically to be aware of these biases and how to overcome them. In his book Psychology of Intelligence Analysis, retired CIA analyst Richards Heuer wrote that analysts should clearly delineate their assumptions and chains of inference and specify the degree and source of the uncertainty involved in the conclusions. He emphasized procedures to help surface and debate alternative points of view.

Innumeracy

Effective analysts are generally adept with a variety of numerical techniques. However, audiences may not have such literacy with numbers or numeracy; they are said to be innumerate. Persons communicating the data may also be attempting to mislead or misinform, deliberately using bad numerical techniques.

For example, whether a number is rising or falling may not be the key factor. More important may be the number relative to another number, such as the size of government revenue or spending relative to the size of the economy (GDP) or the amount of cost relative to revenue in corporate financial statements. This numerical technique is referred to as normalization or common-sizing. There are many such techniques employed by analysts, whether adjusting for inflation (i.e., comparing real vs. nominal data) or considering population increases, demographics, etc. Analysts apply a variety of techniques to address the various quantitative messages described in the section above.

Analysts may also analyze data under different assumptions or scenarios. For example, when analysts perform financial statement analysis, they will often recast the financial statements under different assumptions to help arrive at an estimate of future cash flow, which they then discount to present value based on some interest rate, to determine the valuation of the company or its stock. Similarly, the CBO analyzes the effects of various policy options on the government's revenue, outlays and deficits, creating alternative future scenarios for key measures.

Other topics

Smart buildings

A data analytics approach can be used in order to predict energy consumption in buildings. The different steps of the data analysis process are carried out in order to realise smart buildings, where the building management and control operations including heating, ventilation, air conditioning, lighting and security are realised automatically by miming the needs of the building users and optimising resources like energy and time.

Analytics and business intelligence

Analytics is the "extensive use of data, statistical and quantitative analysis, explanatory and predictive models, and fact-based management to drive decisions and actions." It is a subset of business intelligence, which is a set of technologies and processes that use data to understand and analyze business performance.

Education

Analytic activities of data visualization users

In education, most educators have access to a data system for the purpose of analyzing student data. These data systems present data to educators in an over-the-counter data format (embedding labels, supplemental documentation, and a help system and making key package/display and content decisions) to improve the accuracy of educators’ data analyses.

Practitioner notes

Initial data analysis

The most important distinction between the initial data analysis phase and the main analysis phase, is that during initial data analysis one refrains from any analysis that is aimed at answering the original research question. The initial data analysis phase is guided by the following four questions:

Quality of data

The quality of the data should be checked as early as possible. Data quality can be assessed in several ways, using different types of analysis: frequency counts, descriptive statistics (mean, standard deviation, median), normality (skewness, kurtosis, frequency histograms, n: variables are compared with coding schemes of variables external to the data set, and possibly corrected if coding schemes are not comparable.
The choice of analyses to assess the data quality during the initial data analysis phase depends on the analyses that will be conducted in the main analysis phase.

Quality of measurements

The quality of the measurement instruments should only be checked during the initial data analysis phase when this is not the focus or research question of the study. One should check whether structure of measurement instruments corresponds to structure reported in the literature.

There are two ways to assess measurement: [NOTE: only one way seems to be listed]
  • Analysis of homogeneity (internal consistency), which gives an indication of the reliability of a measurement instrument. During this analysis, one inspects the variances of the items and the scales, the Cronbach's α of the scales, and the change in the Cronbach's alpha when an item would be deleted from a scale.

Initial transformations

After assessing the quality of the data and of the measurements, one might decide to impute missing data, or to perform initial transformations of one or more variables, although this can also be done during the main analysis phase.

Possible transformations of variables are:
  • Square root transformation (if the distribution differs moderately from normal);
  • Log-transformation (if the distribution differs substantially from normal);
  • Inverse transformation (if the distribution differs severely from normal);
  • Make categorical (ordinal / dichotomous) (if the distribution differs severely from normal, and no transformations help).

Did the implementation of the study fulfill the intentions of the research design?

One should check the success of the randomization procedure, for instance by checking whether background and substantive variables are equally distributed within and across groups.
If the study did not need or use a randomization procedure, one should check the success of the non-random sampling, for instance by checking whether all subgroups of the population of interest are represented in sample.

Other possible data distortions that should be checked are:
  • dropout (this should be identified durin. the initial data analysis phase);
  • Item nonresponse (whether this is random or not should be assessed during the initial data analysis phase);
  • Treatment quality (using manipulation checks).

Characteristics of data sample

In any report or article, the structure of the sample must be accurately described. It is especially important to exactly determine the structure of the sample (and specifically the size of the subgroups) when subgroup analyses will be performed during the main analysis phase.

The characteristics of the data sample can be assessed by looking at:
  • Basic statistics of important variables;
  • Scatter plots;
  • Correlations and associations;
  • Cross-tabulations;

Final stage of the initial data analysis

During the final stage, the findings of the initial data analysis are documented, and necessary, preferable, and possible corrective actions are taken.

Also, the original plan for the main data analyses can and should be specified in more detail or rewritten.

In order to do this, several decisions about the main data analyses can and should be made:
  • In the case of non-normals: should one transform variables; make variables categorical (ordinal/dichotomous); adapt the analysis method?
  • In the case of missing data: should one neglect or impute the missing data; which imputation technique should be used?
  • In the case of outliers: should one use robust analysis techniques?
  • In case items do not fit the scale: should one adapt the measurement instrument by omitting items, or rather ensure comparability with other (uses of the) measurement instrument(s)?
  • In the case of (too) small subgroups: should one drop the hypothesis about inter-group differences, or use small sample techniques, like exact tests or bootstrapping?
  • In case the randomization procedure seems to be defective: can and should one calculate propensity scores and include them as covariates in the main analyses?

Analysis

Several analyses can be used during the initial data analysis phase:
  • Univariate statistics (single variable);
  • Bivariate associations (correlations);
  • Graphical techniques (scatter plots).
It is important to take the measurement levels of the variables into account for the analyses, as special statistical techniques are available for each level:
  • Nominal and ordinal variables
    • Frequency counts (numbers and percentages);
    • Associations
      • circumambulations (crosstabulations);
      • hierarchical loglinear analysis (restricted to a maximum of 8 variables);
      • loglinear analysis (to identify relevant/important variables and possible confounders);
    • Exact tests or bootstrapping (in case subgroups are small);
    • Computation of new variables;
  • Continuous variables
    • Distribution;
      • Statistics (M, SD, variance, skewness, kurtosis);
      • Stem-and-leaf displays;
      • Box plots;

Nonlinear analysis

Nonlinear analysis will be necessary when the data is recorded from a nonlinear system. Nonlinear systems can exhibit complex dynamic effects including bifurcations, chaos, harmonics and subharmonics that cannot be analyzed using simple linear methods. Nonlinear data analysis is closely related to nonlinear system identification.

Main data analysis

In the main analysis phase analyses aimed at answering the research question are performed as well as any other relevant analysis needed to write the first draft of the research report.

Exploratory and confirmatory approaches

In the main analysis phase either an exploratory or confirmatory approach can be adopted. Usually the approach is decided before data is collected. In an exploratory analysis no clear hypothesis is stated before analysing the data, and the data is searched for models that describe the data well. In a confirmatory analysis clear hypotheses about the data are tested.

Exploratory data analysis should be interpreted carefully. When testing multiple models at once there is a high chance on finding at least one of them to be significant, but this can be due to a type 1 error. It is important to always adjust the significance level when testing multiple models with, for example, a Bonferroni correction. Also, one should not follow up an exploratory analysis with a confirmatory analysis in the same dataset. An exploratory analysis is used to find ideas for a theory, but not to test that theory as well. When a model is found exploratory in a dataset, then following up that analysis with a confirmatory analysis in the same dataset could simply mean that the results of the confirmatory analysis are due to the same type 1 error that resulted in the exploratory model in the first place. The confirmatory analysis therefore will not be more informative than the original exploratory analysis.

Stability of results

It is important to obtain some indication about how generalizable the results are. While this is hard to check, one can look at the stability of the results. Are the results reliable and reproducible? There are two main ways of doing this:
  • Cross-validation: By splitting the data in multiple parts we can check if an analysis (like a fitted model) based on one part of the data generalizes to another part of the data as well;
  • Sensitivity analysis: A procedure to study the behavior of a system or model when global parameters are (systematically) varied. One way to do this is with bootstrapping.

Statistical methods

Many statistical methods have been used for statistical analyses. A very brief list of four of the more popular methods is:

Free software for data analysis

  • DevInfo – a database system endorsed by the United Nations Development Group for monitoring and analyzing human development;
  • ELKI – data mining framework in Java with data mining oriented visualization functions;
  • KNIME – the Konstanz Information Miner, a user friendly and comprehensive data analytics framework;
  • Orange – A visual programming tool featuring interactive data visualization and methods for statistical data analysis, data mining, and machine learning;
  • PAST – free software for scientific data analysis;
  • PAW – FORTRAN/C data analysis framework developed at CERN;
  • R – a programming language and software environment for statistical computing and graphics;
  • ROOT – C++ data analysis framework developed at CERN;
  • SciPy and Pandas – Python libraries for data analysis.

International data analysis contests

Different companies or organizations hold a data analysis contests to encourage researchers utilize their data or to solve a particular question using data analysis. A few examples of well-known international data analysis contests are as follows.

Quality assurance

From Wikipedia, the free encyclopedia
Quality assurance (QA) is a way of preventing mistakes and defects in manufactured products and avoiding problems when delivering solutions or services to customers; which ISO 9000 defines as "part of quality management focused on providing confidence that quality requirements will be fulfilled". This defect prevention in quality assurance differs subtly from defect detection and rejection in quality control, and has been referred to as a shift left as it focuses on quality earlier in the process i.e. to the left of a linear process diagram reading left to right.

The terms "quality assurance" and "quality control" are often used interchangeably to refer to ways of ensuring the quality of a service or product. For instance, the term "assurance" is often used as follows: Implementation of inspection and structured testing as a measure of quality assurance in a television set software project at Philips Semiconductors is described. The term "control", however, is used to describe the fifth phase of the Define, Measure, Analyze, Improve, Control (DMAIC) model. DMAIC is a data-driven quality strategy used to improve processes.

Quality assurance comprises administrative and procedural activities implemented in a quality system so that requirements and goals for a product, service or activity will be fulfilled. It is the systematic measurement, comparison with a standard, monitoring of processes and an associated feedback loop that confers error prevention. This can be contrasted with quality control, which is focused on process output.

Quality assurance includes two principles: "Fit for purpose" (the product should be suitable for the intended purpose); and "right first time" (mistakes should be eliminated). QA includes management of the quality of raw materials, assemblies, products and components, services related to production, and management, production and inspection processes. The two principles also manifest before the background of developing (engineering) a novel technical product: The task of engineering is to make it work once, while the task of quality assurance is to make it work all the time.

Historically, defining what suitable product or service quality means has been a more difficult process, determined in many ways, from the subjective user-based approach that contains "the different weights that individuals normally attach to quality characteristics," to the value-based approach which finds consumers linking quality to price and making overall conclusions of quality based on such a relationship.

History

Initial efforts to control the quality of production

During the Middle Ages, guilds adopted responsibility for the quality of goods and services offered by their members, setting and maintaining certain standards for guild membership.

Royal governments purchasing material were interested in quality control as customers. For this reason, King John of England appointed William de Wrotham to report about the construction and repair of ships. Centuries later, Samuel Pepys, Secretary to the British Admiralty, appointed multiple such overseers to standardize sea rations and naval training.

Prior to the extensive division of labor and mechanization resulting from the Industrial Revolution, it was possible for workers to control the quality of their own products. The Industrial Revolution led to a system in which large groups of people performing a specialized type of work were grouped together under the supervision of a foreman who was appointed to control the quality of work manufactured.

Wartime production

During the time of the First World War, manufacturing processes typically became more complex, with larger numbers of workers being supervised. This period saw the widespread introduction of mass production and piece work, which created problems as workmen could now earn more money by the production of extra products, which in turn occasionally led to poor quality workmanship being passed on to the assembly lines. Pioneers such as Frederick Winslow Taylor and Henry Ford recognized the limitations of the methods being used in mass production at the time and the subsequent varying quality of output. Taylor, utilizing the concept of scientific management, helped separate production tasks into many simple steps (the assembly line) and limited quality control to a few specific individuals, limiting complexity. Ford emphasized standardization of design and component standards to ensure a standard product was produced, while quality was the responsibility of machine inspectors, "placed in each department to cover all operations ... at frequent intervals, so that no faulty operation shall proceed for any great length of time."

Out of this also came statistical process control (SPC), which was pioneered by Walter A. Shewhart at Bell Laboratories in the early 1920s. Shewhart developed the control chart in 1924 and the concept of a state of statistical control. Statistical control is equivalent to the concept of exchangeability developed by logician William Ernest Johnson also in 1924 in his book Logic, Part III: The Logical Foundations of Science. Along with a team at AT&T that included Harold Dodge and Harry Romig, he worked to put sampling inspection on a rational statistical basis as well. Shewhart consulted with Colonel Leslie E. Simon in the application of control charts to munitions manufacture at the Army's Picatinny Arsenal in 1934. That successful application helped convince Army Ordnance to engage AT&T's George Edwards to consult on the use of statistical quality control among its divisions and contractors at the outbreak of World War II.

Postwar

In the period following World War II, many countries' manufacturing capabilities that had been destroyed during the war were rebuilt. General Douglas MacArthur oversaw the re-building of Japan. During this time, General MacArthur involved two key individuals in the development of modern quality concepts: W. Edwards Deming and Joseph Juran. Both individuals, as well as others, promoted the collaborative concepts of quality to Japanese business and technical groups, and these groups utilized these concepts in the redevelopment of the Japanese economy.

Although there were many individuals trying to lead United States industries towards a more comprehensive approach to quality, the U.S. continued to apply the Quality Control (QC) concepts of inspection and sampling to remove defective product from production lines, essentially unaware of or ignoring advances in QA for decades.

Approaches

Failure testing

A valuable process to perform on a whole consumer product is failure testing or stress testing. In mechanical terms this is the operation of a product until it fails, often under stresses such as increasing vibration, temperature, and humidity. This exposes many unanticipated weaknesses in a product, and the data is used to drive engineering and manufacturing process improvements. Often quite simple changes can dramatically improve product service, such as changing to mold-resistant paint or adding lock-washer placement to the training for new assembly personnel.

Statistical control

Statistical control is based on analyses of objective and subjective data. Many organizations use statistical process control as a tool in any quality improvement effort to track quality data. Any product can be statistically charted as long as they have a common cause variance or special cause variance to track.

Walter Shewart of Bell Telephone Laboratories recognized that when a product is made, data can be taken from scrutinized areas of a sample lot of the part and statistical variances are then analyzed and charted. Control can then be implemented on the part in the form of rework or scrap, or control can be implemented on the process that made the part, ideally eliminating the defect before more parts can be made like it.

Total quality management

The quality of products is dependent upon that of the participating constituents, some of which are sustainable and effectively controlled while others are not. The process(es) which are managed with QA pertain to Total Quality Management.

If the specification does not reflect the true quality requirements, the product's quality cannot be guaranteed. For instance, the parameters for a pressure vessel should cover not only the material and dimensions but operating, environmental, safety, reliability and maintainability requirements.

Models and standards

ISO 17025 is an international standard that specifies the general requirements for the competence to carry out tests and or calibrations. There are 15 management requirements and 10 technical requirements. These requirements outline what a laboratory must do to become accredited. Management system refers to the organization's structure for managing its processes or activities that transform inputs of resources into a product or service which meets the organization's objectives, such as satisfying the customer's quality requirements, complying with regulations, or meeting environmental objectives. WHO has developed several tools and offers training courses for quality assurance in public health laboratories.

The Capability Maturity Model Integration (CMMI) model is widely used to implement Process and Product Quality Assurance (PPQA) in an organization. The CMMI maturity levels can be divided into 5 steps, which a company can achieve by performing specific activities within the organization.

Company quality

During the 1980s, the concept of "company quality" with the focus on management and people came to the fore in the U.S. It was considered that, if all departments approached quality with an open mind, success was possible if management led the quality improvement process.

The company-wide quality approach places an emphasis on four aspects (enshrined in standards such as ISO 9001):
  1. Elements such as controls, job management, adequate processes, performance and integrity criteria and identification of records;
  2. Competence such as knowledge, skills, experiences, qualifications
  3. Soft elements, such as personnel integrity, confidence, organizational culture, motivation, team spirit and quality relationships;
  4. Infrastructure (as it enhances or limits functionality).
The quality of the outputs is at risk if any of these aspects is deficient.

QA is not limited to manufacturing, and can be applied to any business or non-business activity, including: design, consulting, banking, insurance, computer software development, retailing, investment, transportation, education, and translation.

It comprises a quality improvement process, which is generic in the sense that it can be applied to any of these activities and it establishes a behavior pattern, which supports the achievement of quality.
This in turn is supported by quality management practices which can include a number of business systems and which are usually specific to the activities of the business unit concerned.

In manufacturing and construction activities, these business practices can be equated to the models for quality assurance defined by the International Standards contained in the ISO 9000 series and the specified Specifications for quality systems.

In the system of Company Quality, the work being carried out was shop floor inspection which did not reveal the major quality problems. This led to quality assurance or total quality control, which has come into being recently.

In practice

Medical industry

QA is very important in the medical field because it helps to identify the standards of medical equipments and services. Hospitals and laboratories make use of external agencies in order to ensure standards for equipment such as X-ray machines, Diagnostic Radiology and AERB. QA is particularly applicable throughout the development and introduction of new medicines and medical devices. The Research Quality Association (RQA) supports and promotes the quality of research in life sciences, through its members and regulatory bodies.

Aerospace industry

The term product assurance (PA) is often used instead of quality assurance and is, alongside project management and engineering, one of the three primary project functions. Quality assurance is seen as one part of product assurance. Due to the sometimes catastrophic consequences a single failure can have for human lives, the environment, a device, or a mission, product assurance plays a particularly important role here. It has organizational, budgetary and product developmental independence meaning that it reports to highest management only, has its own budget, and does not expend labor to help build a product. Product assurance stands on an equal footing with project management but embraces the customer's point of view.

Software development

Software Quality Assurance consists of a means of monitoring the software engineering processes and methods used to ensure quality. The methods by which this is accomplished are many and varied, and may include ensuring conformance to one or more standards, such as ISO 9000 or a model such as CMMI. In addition, enterprise quality management software is used to correct issues such as: supply chain disaggregation and regulatory compliance which are vital among medical device manufacturers.

Using contractors or consultants

Consultants and contractors are sometimes employed when introducing new quality practices and methods, particularly where the relevant skills and expertise are not available within the organization or when allocating the available internal resources are not available. Consultants and contractors will often employ Quality Management Systems (QMS), auditing and procedural documentation writing CMMI, Six Sigma, Measurement Systems Analysis (MSA), Quality Function Deployment (QFD), Failure Mode and Effects Analysis (FMEA), and Advance Product Quality Planning (APQP).

Cooperative

From Wikipedia, the free encyclopedia ...