ci_lower_bound.sql

-- From the Evan Miller's article http://www.evanmiller.org/how-not-to-sort-by-average-rating.html
SELECT widget_id, ((positive + 1.9208) / (positive + negative) - 
	1.96 * SQRT((positive * negative) / (positive + negative) + 0.9604) / 
	(positive + negative)) / (1 + 3.8416 / (positive + negative)) 
AS ci_lower_bound 
FROM widgets 
WHERE positive + negative > 0 
ORDER BY ci_lower_bound DESC;