A Random Walk Down Wall Street
What you will learn
Explain diversification, recurring costs and the limits of an efficient-market framework.
Read and apply
Read the A Random Walk Down Wall Street book page (opens in a new tab)
On the book page, choose one idea relevant to the objective above. Write what evidence would support it and what could weaken it. Then complete the filing or source activity below and return to these course questions.
Check your understanding
Choose an answer, then open the feedback.
What is one purpose of broad diversification?
A. Eliminate all losses. B. Reduce dependence on one company or sector. C. Guarantee an index return.Show answer and feedback
B. Diversification spreads company-specific exposure, while market risk remains.
What does the efficient-market discussion challenge?
A. The ease of repeatedly exploiting public information after costs. B. The need to compare risk. C. The existence of price changes.Show answer and feedback
A. The theory is a framework with limits, not a promise that prices are always right.
Why do investment costs matter in an index approach?
A. They remove volatility. B. They predict the next market cycle. C. They reduce the return an investor keeps.Show answer and feedback
C. Recurring costs affect net outcomes over time.
Why question: Why is a past chart pattern insufficient to promise a future return?
Show a sample explanation
The pattern is historical; future information, prices and investor behavior may differ, and trading costs can erode results.
Try the diversification model
Open the course allocation calculator. Open the course allocation calculator with its default age-35, moderate-risk, long-horizon, balanced-goal and $50,000 inputs. Record the mix, then change only risk to Conservative and describe what shifts. This model illustrates a trade-off, not an expected return.
Key takeaways
- Diversification spreads company-specific exposure, while market risk remains.
- The theory is a framework with limits, not a promise that prices are always right.
- Recurring costs affect net outcomes over time.
This activity is for financial education. An example or book framework does not guarantee investment results.
AI responses are for educational purposes. Always verify with official course materials.
This lesson teaches a concept. It is general education, not advice about your money. Before you act on anything you learn here, speak to someone licensed.
Sources and reference material
Primary sources and original reference material for the concepts discussed on this page.
- Burton G. Malkiel: A Random Walk Down Wall Street (publisher record)
- Eugene Fama: Efficient Capital Markets II, Journal of Finance
- FINRA: Active vs. Passive Investing
References added 14 October 2026.
AI responses are for educational purposes. Always verify with official course materials.
This lesson teaches a concept. It is general education, not advice about your money. Before you act on anything you learn here, speak to someone licensed.
This lesson teaches a concept. It is general education, not advice about your money. Before you act on anything you learn here, speak to someone licensed.
