Exploration of the stars (ratings)

September 27, 2005 / Filed under: Design, Usability

I mentioned a while ago how the web and desktop applications are more frequently using a system of "star ratings," in order to "rate" what you are experiencing.

This is a great way to "aggregate" similar content - for example, a collection of all of your favorite songs.

"Star ratings," however beneficial they may seem, have some very large drawbacks, which are generating much confusion.

Netflix movies

For example, at Netflix - I have a choice to rate each movie I see, with a number of stars. One star is the lowest, and five stars is the highest.

It seems pretty straight-forward, especially when I really like a particular movie. The only issue, then, is to decide whether to give the movie four or five stars.

But what happens when I don’t like a particular movie? Better yet - what happens when I really dislike a movie?

Do I give it one star? Most would say "yes."

But take a second to think about what you are doing. By giving something just a single star, aren’t you still elevating it in some way? After all, when you give something a star, you are saying there is something "good" about it.

iTunes songs

Another good example is iTunes. In iTunes, you can also give each song a star rating of 1-5.

And, like I said before, it’s real easy when I really like a particular song. But my problem arrives when I don’t like a particular song.

Why would I even bother rating it low? My theory is... if I don’t like I a song - why do I even keep it around? Why should I waste valuable space on my iPod (or hard drive) with songs I don’t even like?

Well... there’s a couple reasons:

  1. Although a single song is bad - that song is still part of an entire album, which means I would never delete just a single song. The whole beauty of an album is the immersion of each track, next to each other.
  2. It’s not cost-effective to pay for songs, and then trash them. So, knowing this, the extra disk space is not that big of a deal.

But... my point stands. I don’t find any need to rate a song with only one or two stars. For songs I don’t like - I just ignore them.

Visual design

The problem with "star ratings" is that they are not good visuals, when it comes to rating systems.

The reason being, as mentioned before, is that giving something just a single star still elevates is somewhat.

If you truly dislike something, it shouldn’t be "elevated" at all.

The "visual appearance" of such a rating system is extremely important.

A "star" icon presents the feeling of something good. However, if Netflix and iTunes used dead squirrel icons in their star rating systems - I don’t think many people would rate their movies too high.

As you can see, we are mixing the "whole-hearted" value of an icon, with a scale of acceptance.

This is where the visual design comes into play.

Rather than using stars that are all the same size:

Screen shot of Netflix star rating system Screen shot of iTunes star rating system

... each star should be a different size, to indicate "strength," or "weight."

Five stars illustrating a rating system

Above we see a four star rating.

Five stars illustrating a rating system

A little different shape, at a five star rating.

In both cases, the size of the star also indicates it’s importance.

These examples are just "exploration." It would be very hard to implement such a rating system on a web page.

Comments/Mentions

# Jennifer Grucza at 9/28/2005 9:40 am cst

Hmm, interesting idea.

Here's another question: how would you represent something that had no rating yet?

# Matthom at 9/28/2005 12:19 pm cst

Jennifer, that's interesting - because iTunes HIDES the stars, but Netflix just shows them "grayed out."

Representing that in a more "creative" way is definitely something to explore.

# Becky at 10/5/2005 7:37 am cst

I like that Netflix also has a "not interested" button. For me, that's the best way indicate the movies I hate.

# Matthom at 10/5/2005 8:57 am cst

Becky, it seems that movies rated as 'not interested' don't show up in my ratings total. I wonder how those movies are "grouped," and if they are used to generate suggestions (or lack of suggestions, in this case).