Hold on to your hats. The barrage of election-year statistics is upon us.

Politicians want to persuade you, so they will pick the statistics that support their cases. They may even try to fool you, knowing that the odds of tricking you are on their side. Let's face it, even if you're sharper than most people, you probably never had a statistics course. Your high school probably didn't even offer one. And at college, the popularity of statistics courses rates somewhere between watching your toenails grow and listening to a nose flute concert.

But don't despair. Here, just in time for the election, is a short course that will help you through the treacherous rapids of political fast-talking. There are five statistics politicians will use to trick you this fall in the election-year debates and discussions:

(1) The Everything's-Going-Up Statistic: Politicians love to claim that more people are employed (or receiving support payments, or whatever) than ever before. They're right. But this is because there are more people than ever before. A more accurate statistic is the employment rate (or the portion of the population receiving support payments, etc.).

Because of inflation, the Everything's-Going-Up statistic is especially tricky when used to make a point about money. For example, politicians might boast that the median family income rose from 1973 to 1980 by about $12,000 -- or 60 percent. But if you adjust for inflation (using what are called "constant" dollars), you see that income actually decreased by about $1,300 in 1980 "constant" dollars -- to minus 6 percent.

We all heard another example of the Everything's-Going-Up statistic at a recent political convention, where it was claimed that the other party had run up a bigger deficit in their four years than all the other presidents since George Washington combined.

Of course, those politicians "forgot" to use "constant" dollars. That means they added an 1803 dollar (when you could buy the whole Louisiana territory for $15 million) to a 1983 dollar (when you can't even buy a square block of New Orleans for that). A $180 billion deficit is a lot of money. But if you adjust for inflation and add up the deficits just from 1940 on, you find a total almost three times greater than the deficit for the accused party.

(2) The Best-Foot Statistic: Here the politicians put their best foot forward by selecting the one of several variants that best supports their case. For example, they could choose between the median family income and the mean family income. The median family income is the income figure where half of the families have higher income and half lower. If the rich get richer and the poor get poorer, the median will stay unchanged.

The mean family income, on the other hand, is the average income for all families. There are only a few very rich families in America. But mean income is dragged up by increases in the incomes of the very rich. If the few rich get richer -- and even if the incomes for the great majority of families remain unchanged -- the mean family income will be dragged up.

An important trick to picking the correct statistic, whether it be mean or median, is to pick the right year for comparison. If politicians want to show an increase in family income, they compare the present with a recession year. For example, comparing 1980 with 1975, they can show that median family income has increased about $10,000 (using unadjusted dollars, of course). If they wanted to be honest, they could use 1980 constant dollars, but then median income would only increase about $20 -- not much to crow about.

If they want to show that income has dropped, they compare the present with an earlier, banner year. As we already saw, they could say that, comparing 1980 with 1973, median family income decreased 6 percent.

(3) The Gee-Whiz Statistic: If the politicians can't find a Best-Foot statistic, they'll look for a Gee-Whiz statistic. A Gee-Whiz statistic gives numbers for only part of the population. For example, if the unemployment rate doesn't tell the tale the politicians want, they can talk about the unemployment rate for teen-agers, or the unemployment rate in the industrialized states.

The Gee-Whiz statistic is also known as a Half-Truth statistic. The politicians don't tell you everything you need to know to understand. They'll say that the increases in defense spending from 1980 to 1982 led to increases in the national debt. That's true. But even if we'd held defense spending constant from 1980 to 1982, the debt would still have grown substantially, so there's more to the story. Increased non-defense spending leads to increased deficits as surely as increased defense spending does.

Moreover, the amount of money coming into the treasury from taxes is critical. Obviously, if we collect less in taxes, we go further in debt. The politicians may not tell us these facts. But the Gee-Whiz statistic can be very catchy -- a real zinger on the 6 o'clock news.

(4) The Anecdote Statistic: If politicians are really hard-pressed to find support for their position, they can always find an anecdote. They can quote Mrs. Gladpenny, who lives in Kalamazoo with her cat Fluffy, etc., etc., declaring how the cutting of her support payments was the best thing that ever happened to her. Such politicians can then ignore that cuts of support payments have resulted in a larger portion of the population below the poverty level. Mrs. Gladpenny, after all, is happy.

The flip side of the Anecdote statistic is the Everyone-Is-Average statistic. For example, because the average man can lift more weight than the average woman, it is conveniently forgotten that some women can lift more weight than a large number of men. Gynophobic politicians -- courting their male constituents -- love to use this type of argument to keep all women from being combat soldiers, firefighters or whatever job they want.

(5) The Coincidence Statistic: Here the politicians state that two things have increased (or decreased) together over time and jump directly to the conclusion that one caused the other. This same illogic is also used in cases where one thing went up just as another was going down.

By the "logic" of the Coincidence statistic, rising tides cause rush hours, and birds starting to sing in the morning cause an upsurge in coffee-drinking. Absurd, right? But beware: This same type of statistical "logic" is used by politicians from all sides to "prove" things like lack of established school prayer causes a decline in American morals, or defense spending causes poverty.

Politicians use the Coincidence statistic every time we have a recession: Whoever's in office at that moment is blamed for it. Never mind that a think tank full of economists can't agree on what causes a recession. One thing the economists do know is that recessions are beyond the control of any one politician -- or economist.

A variant of the Coincidence statistic holds that if one event occurs before another, the first event caused the second. We've all heard politicians promise to make kids smarter by getting the school "back to basics." No one can prove, however, that courses in basketweaving cause math scores to go down.

But the same trick of statistical reasoning has been used to make people buy a lot of things -- like "trickle-down" economics, for example. Just because a rise in the incomes of the rich might precede a rise in incomes for the poor, doesn't mean the first caused the second or, indeed, that the second even really happened. As we have already seen, it might actually be because politicians are using that trusty "mean income" statistic, which is dragged up automatically, even if not a single penny has trickled down to the poor.

The election debates should be fun. But be on guard. You'll want to listen carefully and watch for these five tricks before buying the campaign rhetoric.

As British politician and Prime Minister Benjamin Disraeli once put it: "There are three kinds of lies: lies, damned lies and statistics."