After reading a heated discussion in a personal finance forum earlier this week, I thought it would be a great idea to write my thoughts on one of the most intensely debated and discussed issues in finance. This is a question that I ask MBA grads during 1st round interviews. You’d be surprised how often very smart people can sound very stupid when asked if markets are efficient, and what to do about it.

There are two basic schools of thought in regards to investing in the stock market. In one corner we have the active investor. She believes that markets are inherently inefficient. An inefficient market is one where prices do not accurately reflect the value of an asset at that point in time. Therefore, some stocks will be “cheap” and others “expensive”. The goal of the active investor is to purchase the “cheap” stocks and then sell when they match/exceed their true value.

On the flip side we have the passive investor. He believes that the market is efficient and all prices accurately portray the true value of an asset. There are no “cheap” stocks. Everything is priced to perfection for that point in time. Depending on how far the investor is on the passive scale, they either base purchases purely on future expectations, or opt for the ultimate in passive investing: indexing.

Which is the better approach? Read more