NPR logo 17,205 People Guessed The Weight Of A Cow. Here's How They Did.

17,205 People Guessed The Weight Of A Cow. Here's How They Did.

A few weeks ago, we asked the Internet a simple question: how much does this cow weigh?

Over 17,000 people responded.

We wanted to know how good the collective guess of the crowd would be. The idea was to understand this eerie phenomenon that drives everything from the stock market to the price of orange juice. (We explain at length in today's podcast.)

In this case, at least, the collective guess of the crowd was pretty good!

Among all the people in our poll, the average guess was 1,287 pounds. Penelope weighed 1,355 pounds. So the average was only off by 68 pounds (about 5 percent). Interestingly, the crowd was kind of split: people either thought Penelope weighed between 850 and 950 pounds or they thought she weighed between 1,250 and 1,350 pounds.

Interesting side note: Google's answer to "average cow weight" is 1,500 pounds, which is heavier than the cow we weighed, and much higher than most of our guesses.

We asked everyone who responded whether they have ever worked with cows. We wanted to compare their guesses against the crowd as a whole. Self-described cow experts actually did slightly worse than the crowd. Their average guess was off by 83 pounds (or 6 percent).

Update (8/17/2015): Some of you have asked for the raw data used for the graphs above. Here it is with outliers removed.