Hacker News Reader

I was overwhelmed too (here's simple wrong solution #1, here's simple wrong solution #2, here's incredibly complicated but more correct statistical solution #3 that you may not understand) but since this is relevant to my day job and we use PHP, I did find this:

http://www.derivante.com/2009/09/01/php-content-rating-confi...

I'm not a statistician so I can't speak to the correctness of this implementation.

Here's my version that we use on MyBankTracker.com. We hardcode the z variable using a power of 0.05.

https://gist.github.com/2292254

"if you don't have a statistics package handy or if performance is an issue you can always hard-code a value here for z. (Use 1.96 for a confidence level of 0.95.)"

Ouch, I managed not to see that at all. Thanks!

Googling "Wilson score confidence interval php" returns an implementation as the top result.

See this example: http://www.derivante.com/2009/09/01/php-content-rating-confi...

However, if you install the stats package for PHP you can use stats_cdf_normal() as well.

Aren't there libraries for PHP like for other languages?