Los Angeles Times

Economics isn’t unreliable, we are

Most modern financial crises occur because we ignore what we know.

- By John Ioannidis John P. A. Ioannidis isa professor of medicine, health research and policy, biomedical data science, and statistics at Stanford University and a director of its Meta-Research Innovation Center.

The financial crises of the last two decades, and our failure to predict them, have wreaked havoc on more than just the global economy. The bursting of the dot-com bubble in 2000, the Enron scandal and the global financial crisis of 2008 have led to a loss of faith in economics itself.

But these crises and scandals do not mean that the science of economics is inherently unreliable. Most of them occurred because we ignored what we knew.

Perhaps most obviously, we deputized — and continue to deputize — the wrong people as authoritie­s. For instance, many assume that the real experts on the subject of money are those who have a lot of it. But the opinions of wealthy tycoons are often dissociate­d from scientific evidence, out of touch with reality and all too plainly wrong. Amassing wealth as an individual is not the same thing as building and sustaining broad economic growth across nations. Often, making a private fortune is a matter of luck. “Fortuna” is the Latin word for luck, after all.

What’s more, our culture elevates prediction­s about the stock market and the course of the economy at large, when any good economist will tell you that the most advanced models are not much better than gut feeling. Credit rating agencies and highly paid gurus are largely selling products of little or no value to the gullible.

Similarly, politician­s rarely use economic science to make decisions and set new laws. Indeed, it is scary how little science informs political choices on a global scale. Those who decide the world’s economic fate typically have a weak scientific background or none at all.

This isn’t a distinctiv­ely American problem. The Eurogroup, the body of finance ministers from nations that use the euro, does not include any top scientists. The group’s chair, Jeroen Dijsselblo­em, at one point claimed that he held a master’s degree in economics from University College Cork, but he had to remove that statement from his official website because it wasn’t true.

The former finance minister of Greece, Yanis Varoufakis, built his political career on the notion that he is a top-caliber professor of economics. But a search of scientific databases shows that Varoufakis has published only one paper in the 40 most respected journals of economics.

The U.S. government generally has more access to economic knowledge — the Federal Reserve employs several hundred people who hold graduate degrees in economics — and this has helped to curtail the ignorance of some of its politician­s.

Still, knowledge has often gone unheeded. The repeated bursting of bubbles in the real estate market might have been partly averted had standard principles of economics been applied, had someone checked the math more carefully, and had we learned more from past errors.

All that said, while it’s true that economic knowledge is often overlooked, it is also true that there are problems in the field that affect its overall reliabilit­y.

In economics, scientific evidence can come in many different forms — theoretica­l models and simulation­s, observatio­nal and survey data, and experiment­al studies, for example. Not all forms of evidence have equal validity.

Most empirical data do not come from experiment­s but from non-experiment­al sources such as surveys and routinely collected informatio­n. Along with Chris Doucouliag­os and Tom Stanley, my research center examined 6,700 empirical studies encompassi­ng 159 topics. We found that there is probably substantia­l bias in much of this literature.

For example, the value of a statistica­l life, which measures how much people are willing to pay to reduce their risk of death, appears to have been exaggerate­d by a factor of eight. On average, the strength of the results may have been exaggerate­d by a factor of two. In a third of the studies, by a factor of four.

Most published studies use limited data. By a conservati­ve estimate, the average study has 18% power to detect a modest associatio­n if one exists. Due to this low power of prediction, researcher­s could easily miss a genuine associatio­n. Or, they could declare a spurious, non-existing associatio­n, having been , led astray by small amounts of bias.

In several areas, researcher­s are gathering more data than they can possibly analyze, and this is itself becoming a problem. Much of this informatio­n is prone to error, with major biases that are difficult to correct. Results are often cherry-picked and exaggerate­d. Many companies are investing in big data without scrutinizi­ng the quality of the informatio­n.

Thankfully, economists are increasing­ly turning to experiment­al methods, which have the best reproducib­ility record. According to one evaluation, two-thirds of experiment­al studies were fully reproducib­le when other researcher­s tried to repeat them.

Several economics journals, moreover, are now employing standards that are likely to enhance transparen­cy and reproducib­ility. These journals require researcher­s to share all of their protocols, raw data, software and code.

Although the discipline has gotten a bad rap, economics can be quite reliable and trustworth­y. Where evidence is deemed unreliable, we need more investment in the science of economics, not less. Until then, the pseudo experts can claim anything.

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