1. Financial Concepts: Introduction
  2. Financial Concepts: The Risk/Return Tradeoff
  3. Financial Concepts: Diversification
  4. Financial Concepts: Dollar Cost Averaging
  5. Financial Concepts: Asset Allocation
  6. Financial Concepts: Random Walk Theory
  7. Financial Concepts: Efficient Market Hypothesis
  8. Financial Concepts: The Optimal Portfolio
  9. Financial Concepts: Capital Asset Pricing Model (CAPM)
  10. Financial Concepts: Conclusion


Efficient market hypothesis (EMH) is an idea partly developed in the 1960s by Eugene Fama. It states that it is impossible to beat the market because prices already incorporate and reflect all relevant information. This is also a highly controversial and often disputed theory. Supporters of this model believe it is pointless to search for undervalued stocks or try to predict trends in the market through fundamental analysis or technical analysis.

Under the efficient market hypothesis, any time you buy and sell securities, you're engaging in a game of chance, not skill. If markets are efficient and current, it means that prices always reflect all information, so there's no way you'll ever be able to buy a stock at a bargain price.

This theory has been met with a lot of opposition, especially from the technical analysts. Their argument against the efficient market theory is that many investors base their expectations on past prices, past earnings, track records and other indicators. Because stock prices are largely based on investor expectation, many believe it only makes sense to believe that past prices influence future prices.

Financial Concepts: The Optimal Portfolio

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