Their argument that historgrams are just.awful. (I didn't care for the extra periods) seems to have two components: 1. asserting that historgrams are bad 2. showing us 3 histograms and saying they tell you the same thing about all 3 movies, when in fact there is a very clear and important difference between the histograms.
Its completely obvious from inspection ("people are really good at seeing patterns") that Starship Troopers has a much lower percentage of 5 star ratings than the other two, and a much higher fraction of 0 star ratings. It also appears to me that the Fifth Element has a higher fraction of 4 or 5 star ratings, and is probably the most apprciated of the 3 films, although Blade Runner is fairly close.
If you are going to cherry a set of 3 specific films to make your point, you should be sure to at least pick 3 films that support your point instead of refuting it.
We then learn about their hypothesis that while 5-star rating system sucks, a system that relies on two correlated 5-star ratings is great. They demonstrate this by using the two question system to draw the exact same conclusion I drew from the histograms of the 1 question ratings.
I would've liked some sort of objective attempt to compare the two rating systems. Perhaps it would be possible to measure how frequently the two question system leads people to make a better choice than the one question system, or at least some sort of statistical wonkery that would purport to show me that the two question system in practice draws more distinctions than the one question system. Unfortunatley we only get this one rather uninspired example ("watch this if you’re in the mood for something really good").
They also didn't address why "would you re-watch this film" is a better choice than any other second question. There are attempts to justify it being a good question, but no real evidence that other questions were tried and didn't perform.
Finally, the thing that really irked me was that this proposed system doesn't seem to do anything to address most of the actual problems with the regular 5 star system, namely that people who feel really strongly about something are more likely to rate so that most ratings tend towards the extremes, and that without context we have no idea why someone rated something a 5 instead of a 1. Those problems now exist along two dimensions instead of one.
I see this less as an article and more as an advertisement hitching a ride on an xkcd comic.
Speaking as a film buff; this is actually quite a good guide to the sort of movie it is (when combined with quality). If lots of people mark it good quality, but wouldn't watch it again, that implies that you have to be in the right mood for it.
If people mark rewatchability high, even if the quality rating varies, you know it is much more easy going film.
And so on. Combining data points is good :)
Oh well I'll answer your question anyway. Because 90% of everything is crap (probably more than that on P2P sites). Re-watching a movie can be like walking in the same park more than once, looking at pleasant things with a sense of recognition. You could put a movie in to suit your mood. Sometimes you'd rather watch a good "original" movie again than watch yet another crappy remake or rip-off.
This is not about picking a movie to watch again after you have already seen it once: this is about picking a movie you haven't seen but that is so good that other people like to watch it again and again.
So rewatchability roughly translates to "emotional connection + quality".
If you've got kids, you know they'll just watch the same flashy animated movies over and over again, even if their opinion of the content is "meh".
What would probably happen is that family films, especially animated ones, would have skewed results.
Plus, they do not normally use online rating systems...
Yes it would, and the article shows why and how. Scatter plots are easy to read (for comp./math. educated people). Two histograms side by side are easy to read (and find correlations) for nobody.
Also, side-by-side histograms aren't the only way to display two parameters in a single histogram. What about stacked histograms? They scale up to an arbitrary number of parameters and everybody who can read a histogram can read a stacked histogram. Scatter plots seem like thermonuclear overkill for a problem which most movie sites seem to consider to be "solved".
Read the text of the article describing each movie. The correlations are absolutely meaningless. He doesn't hit on them at all. In fact, with comments like "almost nobody" he's specifically looking at averages. Then coming to a conclusion effectively based on the average of Score 1 and the average of Score 2 to determine what type of movie it is.
So on this Quality/Rewatchability grading system:
Starship Troopers: 3:4 The Fifth Element: 4:4 Blade Runner: 4.5:3.8
Drop that in place of the graphs and the conclusions would sound as seemingly valid.
It would be nice if the article actually compared different visualizations of the same data, rather than showing histograms of 2 separate data sets and scatter plots of a 3rd data set.
A scatterplot conveys objectively more information.
Actually it is fundamentally different as the histograms show aggregate data and scatterplots show individual data points.
As far as reading the distribution, two separate histograms are definitely more readable and understandable in order to understand the distribution. Adding the complexity of a scatter plot because it also shows a correlation that people are not actually interested in makes things less understandable.
And when I am looking at user rankings for a movie, almost by definition I am only concerned with rankings for movies I haven't yet seen, since I already have an internal self-ranking for a movie I've seen already.
Histograms are extremely useful for knowing the spread of rankings, which the scatter plot also illuminates.
It looks like they would still give a good picture of the data, as the trends are mostly linear.
If you gave someone those 3 histograms and those 3 scatterplots, I bet they could match them up correctly.
Aside- The scatterplots are an awful user interface because of the cognitive effort to interpret them, but perhaps there's a way to present the same information in a usable way.
Then trying to conclude that some convoluted scatter plot system makes more sense is laughable.
Not to mention, this system is still just a star rating system. This would be no different than having two histograms side by side.. assuming, of course, that you'd even want to rate different aspects of the same thing.
I can't even imagine scatter plots on amazon, or trying to convince the general public that "it makes more sense"