The plebble-rating™ is designed to give a real-time index of customer satisfaction levels for businesses and other organisations.
It ranges from -5 to +5 and is based on a weighted average of the scores from ratings received on Plebble.com plus aggregated ratings from third party rating and review websites.
The calculation gives current ratings a greater influence than historic ones, as it simply doesn't make sense to have a rating two years old holding the same influence as a rating today. The plebble-rating™ therefore uses a declining S-curve equation based on the rates at which things naturally decay in nature. Historic ratings are adjusted by an influence factor which is determined according to the average number of ratings the business/organisation receives per month.
The number that you see next to each business/organisation (the plebble-rating™) is the weighted average of the ratings calculated as described above. The sources which make up the plebble-rating™ for each business/organisation can be viewed under the plebble-rating™ number.