How do you rate a board game? A movie? A restaurant? You want a scale with consistency and clear communication.

What do people normally do?

There are two main scales:

1. A, B, C, D, F
2. 1–5, 1–10, 1–100

These both have the same problem: ambiguity. Everyone has a different idea of which values map to good / bad / meh / average. Is a C "average", or is it falling short of expectations?

Rotten Tomatoes considers < 60 bad, 60–74 good, and 75+ really good.

Metacritic ranges are < 49 is bad, 50–74 is average or uncertain, 75+ is good. So there's a 10 point range (50–59) where Metacritic thinks something is alright, but Rotten Tomatoes doesn't.

Net Promoter Score uses 1–10, but their interpretation is unintuitive. 9–10 are beneficial customers, 7–8 do nothing for you, and ≤ 6 are harmful to your reputation. Before learning this, I figured rating a product an 8 was pretty good!

Amazon, Uber, etc. all use a 5-point scale. A 4.7 means steer clear of that product or driver! Or maybe it's 4.3? Well, definitely avoid anything under 4.

On Google Maps, a 4.7-star restaurant in one city might be a 3.2 in another.

No one can agree on what number even means good vs bad, much less how good or bad! Adding digits of precision only makes things worse: if you're not sure what somebody's 7 vs 8 means, having them give you a 72 sure won't help.

Introducing the "Three" Scale

I have converted all my friends to use this. They start off reluctant: it's weird, and what's wrong with 1 through 10? But they quickly stop grumbling when they see how easy it is to communicate our experiences to each other, and then make decisions from that.

How it works

Everything is rated from −3 to +3.

Zero is neutral: "I have no strong feelings one way on the other". Take it or leave it.

+1 is mild positive sentiment. It's alright, if there's nothing better available.

+2 is strong positive sentiment. You'll normally say 'yes' to eating here, watching this, playing this.

+3 is one of the best of its kind. Your favorite restaurants, and the movies you tell everyone they have to see. It just doesn't get better than this!

Negative numbers are the same, but for hating something.

"Okay but so what?"

Now, you & your friends have a common language for ratings. Now, they're legible.

You agree what's neutral. You agree what's positive, and what's negative. No guessing. There's not much room for ambiguity in between 1 and 3.

If someone in your group gives the restaurant a −1 rating, it's clear that place shouldn't be in the group's normal rotation. If they said −2, you had better have a good reason for going back. If they'd said "C-"... who knows what that means 🤷‍♂️

My wife and I watch the trailers in the movie theater and whisper our ratings. In one word, we each know whether we're going to see a film together, separately, or at all. Whether we'll spend to see it in theaters, or wait for streaming.

I keep a spreadsheet tracking the ratings my board gaming group gives games. Because everyone's speaking the same language, I can sort & group games to see what old favorites we should replay.

The lack of precision helps, not hurts. If this was widened to ±10, we could at least tell positive/neutral/negative, but we'd be back to guessing how a +5 is different from a +7.

I don't think I've found a situation where the Three Scale is worse than letter grades or 1–10.

Some friends and I pondered if it should be cut down to ±2 or ±1, but it's not clear that there's a big win there. ±3 seems like the right granularity to express mild/strong/excessive sentiment.

"I don't want to explain this to people!"

In my experience, you just have to say "I rate things from −3 to +3". That's it — they get it.

In conclusion

It's great! Use it!

Appendix: where did this come from?

I swear I read about this in some medical or social sciences research paper. I recall researchers asked subjects to rate something on the Three Scale, and I loved the idea. But any time I mention this, nobody's ever seen it before. Even people who read social science research.