The Tyranny of Numbers: Mismeasurement and Misrule.

• Author: Doherty, Brian

In the beginning was the Word, but the end will undoubtedly be announced with a number. A solemn poll: Sixty-eight percent disapprove of annihilation; 24 percent support it, with 8 percent undecided. Margin of error, plus or minus 3 percent.

Any consumer of news is surfeited with numbers; no statement can be made, no conclusion reached safely in public discourse nowadays without the cushion of often incomprehensible or irrelevant numbers. The presidential campaign is handicapped with almost daily poll results, even though the readers of the poll are often ignorant about how the relevant questions were asked. (The order and specific wording of the questions can affect the results.) The fate of our economy is forecast not in entrails but in numerals, huge macroaggregates that are actually measuring - what?

The sort of numbers we encounter in newspapers every day can be troublesome on many different levels. Among those problems:

* Practical problems of aggregation. Is it a count or a survey? Do you have reason to trust the sampling techniques if it is a survey? Do you have reason to trust the raw data of especially large counts? An anecdote from novelist Anthony Burgess's memoirs, Little Wilson and Big God, casts light on a problem with data collection that is often ignored, possibly because its ramifications are so unpleasant.

Burgess writes about having to send numerical records back to the home office in London about classes he supposedly taught fellow soldiers while stationed in Gibraltar during World War II. He fabricated them from thin air. Those "statistics were sent to the War Office. These, presumably, got into official records which nobody read." Surely we all have enough anecdotal awareness of similar lapses to guess that these sort of shenanigans are common. The basic counts that underlie the huge numbers we deal with ought not necessarily be trusted. We don't necessarily know everything that a cold number on a page can make us think we know.

* Theoretical problems of the meaning of aggregation. Economic macroaggregates dominate newspaper reporting - trade deficits, GDP, and the like. But what are these numbers good for? The bigger the aggregation, the more places error can creep in; and economic aggregates are often not even direct counts of anything meaningful. Do they tell us anything worth knowing? Overemphasis on such things as trade deficits (or racial population breakdowns) clouds discussion of whether such concepts are worth anyone's concern. Cobbling together macroaggregates and behaving as if they in some way interact to create real-world economic effects is bound to confuse. Knowing those sorts of numbers is not necessarily knowing anything useful about understanding the workings of a national economy. When dealing with areas where causality is as inherently complicated as economics, the wisdom of Austrian economist Ludwig von Mises is apposite: The kind of numerical empiricism implicit in macroaggregates doesn't always lead to useful knowledge of anything but history.

* The intentions of those spreading the numbers. Numbers don't come to the attention of the populace in some ideal Pythagorean way - beamed into our brains, untouched by grubby material considerations. They arrive via an information economy, the retail end of which is usually daily newspapers and TV news shows - media with particular qualities and predilections that make them easy conduits for shoddy or confusing numerical displays.

These four books, all concerned to one degree or another with quality control in the information economy, touch on permutations of all the above difficulties. They all to some degree scrape beneath the varnish to expose the sometimes unfinished and shoddy nature of the scaffolding on which so much public argument stands.

The information economy has a proclivity to spin the audience's mind with so many conflicting reports that neither trained nor untrained minds can be certain of what to believe. In her book Tainted Truth, Wall Street Journal reporter Cynthia Crossen walks her readers step by tortuous step through some current such conflicts related to health: the continuing sagas of caffeine and oat bran, the public scares over Alar and silicone implants. The lesson seems to be that little of the expensive studies and number manipulations of modern medical science have improved much on what the ancient Greeks could have...