Reviewed: The 10-point Rating System

The 10-point Rating System

In The Anthropocene Reviewed by John Green, Green writes his thoughts on the format of the review: “Booklist reviews were limited to 175 words, which meant each sentence must work multiple jobs. Every review had to introduce a book while also analysing it. Your compliments needed to live right alongside your concerns”. 

In many ways, this is what I attempt to do here– except that we get a slightly more generous 2200 characters on Instagram, which converts to about 400 words.

Recently, in my capacity as a resource panel member, I’d had the opportunity to review and user-test some new toolkits on designing ground-up projects for public health. After about an hour of giving our opinions on the various aspects, we were asked to offer a rating out of 10.

The 10-point rating scale doesn’t exist for humans; it exists for data aggregation systems. Everyone's experience is different and thus fundamentally incommensurable. But it is almost impossible to quantify experiences, and so we settle for lesser measures like ratings.

There were about five of us in the call. Some ratings were given as “7.5” or “8.5”. I offered a “7”.

Another common rating measure is the 5-star scale. My view is that the only way to make these two systems interoperable, is that the 10-point system must thus disallow decimal points. 

My error was in applying the mental shortcut that 5 is the midpoint grade of 10. On a 5-star scale, I realise that because 0 is not an option and 5 is the maximum rating, the midpoint is actually 3 and not 2.5. This is consistent with what we perceive as “Neutral”. I would have given 4 stars in this case, which rightfully translates to 8-points. I note this for the future, that I could sooner grade on a five-star scale, and then convert it up.

I followed up with an email affirming the team on the effort and research done to develop such a resource from the ground up, which is a tall order.

Green continues: “[W]hen people write reviews, they are really writing a kind of memoir– here’s what my experience was eating at this restaurant or getting my hair cut at this barbershop”. 

I give the 10-point rating system two and a half stars.