According to a recent article by Barron’s Magazine title The Cramer Effect (& Defect), readers who follow Jim Cramer’s stock picks from his show are more than likely to lose money in the long run.

We also looked at a database of Cramer’s Mad Money picks maintained by his Website, TheStreet.com. It covers only the past six months, but includes an astounding 3,458 stocks — Buys mainly, punctuated by some Sells. These picks were flat to down in relation to the market. Count commissions and you would have been much better off in an index fund that simply tracks the market.

When we asked Cramer and CNBC for their own records of Mad Money’s stock-picking performance, they had more excuses than a Tour de France cyclist dodging a blood test. They complained that the list from YourMoneyWatch.com contained some stocks from the program’s “Lightning Round,” in which Cramer gives a quick analysis and a buy or sell decision on stocks phoned in live by viewers. These, they argued, shouldn’t count in our tally.

CNBC officials also said that viewers should buy Cramer’s picks a week after they’re aired. They said that the show is mainly educational, and not just about stock-picking. In the end, they said we should focus only on the tiny universe of stock selections — about 12 a week — that Cramer researches the most. And we should do it only for the issues picked this year. CNBC analyzed these stocks, and said that if held for one month, they beat the S&P by 0.8%, or 1.7% after two months. They offered no results for the year-to-date.

It turns out that CNBC did its analysis incorrectly, and that the stocks beat the S&P by 0.4% in one month and 1.2% over two months. CNBC measured the stocks’ performance against the average performance of the S&P year-to-date, instead of against the performance of the S&P from the date of each stock pick. Also, it included more than 100 recently recommended stocks that weren’t held for the full one- or two-month holding period that CNBC claimed.

More important, the stocks fell short of the S&P by a statistically significant 2.2% through last week.

Our question is: How are viewers supposed to know that they should pay attention only to this subset of stock picks each week and ignore the thousands of others that Cramer makes on his show?

Then there’s the day-after-pop phenomenon. Our analysis of Cramer’s picks over the past two years, from YourMoneyWatch.com, showed that, on average, the stocks jumped 2% the day after he mentioned them. From there, they usually moved sideways or down for the following 30 trading days (see chart). This offered an opportunity to make money — 5% to 30% a year — by selling Cramer’s selections short.

Cramer agrees that there is a shorting opportunity in the temporary effect he has on stocks — a trade that he’d jump on if he still were at a hedge fund. “If you short the bump, you will do well,” he said last week. “I’ve said it on the show many times.”

I really don’t think people should be taking stock tips from a guy who has about a minute to analyze the stocks on his show. He may be a really smart guy but how can he properly evaluate a stock in the short time period he has?

I hope there aren’t too many people who base their stock investing solely based on his recommendations. But if they’re that ignorant or lazy, I guess they get what they deserve!