J. M. Keyes put all his money in on tock, and the stock doubled in value in a matter of months. He did this three times in a row with three different stocks. J. M. got his picture on the front page of the Wall Street Journal. However, the paper never mentioned the thousands of investors who made similar bets on other stocks and lost most of their money. This is an example of the problem in deciding how efficient the markets are.
a. Magnitude
b. Selection bias
c. Lucky event
d. Small firm

c.Lucky event.

Explanation:

This an example of lucky event problem.

Since for every one successful manager, there are many managers who lost, who are not brought into lime light.

Magnitude problem means only managers with high amount of investments will show considerable profits.

Selection bias means only those with portfolios which generate profits are published.

you can lose ranking 2 ways.

1) you don't have enough points due to you expending them by asking questions/your answers are deleted.

2) your brainliest's expired. this means that brainliests, once they exceed the 30 day limit, expires. this is to ensure that you continue to contribute into the community at a constant rank if you want to continue to have/exceed the rank you have right now.

if you go to profile, and click "show more information" located on the bottom left of the box with your information (on top of the questions answered, questions asked, and friends), you will be given the following information (example):

member since : 02/13/2017, 18: 11

questions answered: 9741

questions asked: 162

no. of brainliest answers: 1575

brainliest answers in last 30 days: 10

warnings: 0 view

questions/answers reported: 2637

questions/answers incorrectly reported: 64

look at the "brainliest answers in the last 30 days". this is the one that will affect your rank other than your points. again, once your brainliest expires (was earned 31+ days ago), it will not be counted.

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