Let’s skip the mathematical definition. Capturing alpha means making more money in the stock market than the mathematicians think you should be able to make.
Of course you can make money in a bull market. Buy an index fund and hold it. That is not capturing alpha.
If people are allowed to bet more than they can afford to lose, some of them will do very well. That’s what caused the recent financial and housing crashes. That is not capturing alpha. That’s luck.
Capturing alpha requires a lot of work and the best tools. Capturing alpha means constantly doing better than the average stock trader. At Trade-Ideas, our tools are not for the person who’s curious about his 401k, or trying to leverage himself more than is usually allowed. Our tools are designed to give traders the best advantages so they can capture alpha.