---
title: "100-Day Reading Sharing Plan — Day 65"
type: "Topics"
locale: "en"
url: "https://longbridge.com/en/topics/38760420.md"
description: "$Cleveland Cliffs(CLF.US) $Novo Nordisk AS(NVO.US) $Amazon(AMZN.US) LOL 😆 "A Random Walk Down Wall Street" 1. In statistical terms, the covariance of the two companies' returns is negative. As long as there is a lack of co-movement in the profitability of individual companies within the economy, diversification can reduce risk. 2. Using a theory that is only correct half the time to guide practice is less economical than flipping a coin. 3. Roughly speaking, there are four factors that allow irrational market behavior to exist..."
datetime: "2026-02-17T14:57:00.000Z"
locales:
  - [en](https://longbridge.com/en/topics/38760420.md)
  - [zh-CN](https://longbridge.com/zh-CN/topics/38760420.md)
  - [zh-HK](https://longbridge.com/zh-HK/topics/38760420.md)
author: "[长期主义接班人](https://longbridge.com/en/profiles/16386327.md)"
---

# 100-Day Reading Sharing Plan — Day 65

$Cleveland Cliffs(CLF.US) $Novo Nordisk AS(NVO.US) $Amazon(AMZN.US) LOL😆

"A Random Walk Down Wall Street"

1\. In statistical terms, the covariance of the two companies' returns is negative). As long as there is a lack of consistent co-movement in the profitability of individual companies within the economy, diversification can reduce risk.

2\. Using a theory that is correct only half the time to guide practice is less economical than flipping a coin.

3\. Roughly speaking, there are four factors that allow irrational market behavior to exist: overconfidence, judgment bias, herd mentality, and loss aversion.

4\. The fancy term "arbitrage traders" is used to describe a type of person who trades to profit whenever market prices deviate from their rational value.

5\. In experiments with college students, it was found that 80% to 90% of subjects always claimed to be better and safer drivers than their classmates.

### Related Stocks

- [AMZN.US](https://longbridge.com/en/quote/AMZN.US.md)
- [CLF.US](https://longbridge.com/en/quote/CLF.US.md)
- [NVO.US](https://longbridge.com/en/quote/NVO.US.md)

## Comments (2)

- **Soul C · 2026-02-17T15:03:57.000Z**: Happy New Year🎉🎉
  - **长期主义接班人** (2026-02-17T15:05:33.000Z): Happy New Year!