Hacker News new | ask | show | jobs
by mcherm 3901 days ago
He never said that the mode was 0.5... he said "The mode (most common number) will be below [1 search per day] too."

And it is. According to his numbers, the mode is precisely 0. The most common number of searches is zero... more people do 0 Google searches in a day than do 7 or 1 or any other specific number.

This is not a USEFUL statistic, but (according to this data) it is accurate.

2 comments

> According to his numbers, the mode is precisely 0.

I was referring to the fact that the graphs - e.g. https://theoverspill.files.wordpress.com/2015/10/screenshot-... - are using using mode = 0.5

Actually, it's not. He's taken the mean average over the course of 30 days to get the average number of searches per day for all users. That doesn't give you the average number of searches per user per day!

In order to get the mode, you'd need to know how many searches each person does each day. You can't get the mode from the figures he's been provided.

But in the article, he wrote:

"I tried modelling what search activity probably looks like on mobile: I used a mean = 0.925 (as per Singhal) and mode = 0.5. The mode must be below the mean because of the long tail of higher values; 0.5 is a guess, but moving it around doesn’t have a large effect. This gives a median of 0.94, close to the mean, which you’d also expect."

He made some guesstimates which he used as input parameters to form a Pareto Distribution.

As for the mode always being less than the mean, that's wrong too.