It’s been more than four years since Zomato started. Over these years, we have served about 55 million visitors on Zomato through our website and mobile apps. Zomato ratings have over time become the de facto look up system for our customers to decide whether they should  visit a particular restaurant or not.

Given the traffic on Zomato, a lot of restaurant owners, or their agents (PR companies), or competitors try to game the system by giving out unfair positive or negative ratings for restaurants on Zomato. This leads to a huge amount of what we call “rating spam” in the system. This eventually leads to a poor customer experience on the website, eventually making Zomato lose credibility in the eyes of the customer.

However, with all the experience we have with us, we have made some significant improvements to our system to weed out spam and unworthy votes from the system. Broadly, we have classified user behaviour on the website on the scale of 1 to 10, where 1 is ‘dubious’ and 10 is ‘trustworthy’. So, overall, from today onwards, any ratings from ‘dubious’ users do not count towards the ratings aggregates shown on Zomato; whereas we are allocating more weight to users who we deem to be ‘trustworthy’.

There are still some things we need to improve and think about. For example, the votes count next to the ratings shows the total votes received for the restaurant. Not necessarily the votes being considered towards the aggregate. We are not sure yet if we should be that transparent. In our opinion, more transparency leads to more spam, which is something nobody wants (e.g. Google never reveals its search ranking algorithms).

Also, there is a lot of science going behind classifying users between ‘dubious’ and ‘trustworthy’. This is a mix of manual and algorithmic grading. Our users who we have met in real life (we meet a lot of our users over lunches :-)), are automatically given 10 on the trust scale.

I am hoping this will go a long way towards improving the authenticity of ratings being shown on Zomato, and help our valued users discover more great places to eat around them.