In parallel to my series of posts on famous statisticians, I also seem to be running a series of posts on characters from the Mr. Men books. Previously we had a post about Mr. Wrong. And now I have to tell you about Mr. Greedy. In doing so, you’ll hopefully learn something about the limitation of Statistics.
It was widely reported in the media last weekend (here, here and here for example) that a recent study had shown that the Mr. Greedy book is as complex a work of literature as various American classics including ‘Of Mice and Men’ and ‘The Grapes of Wrath’, each by John Steinbeck, the latter having won the Pulitzer prize for literature.
To cut a long story short, the authors of the report have developed a method of rating the readability of a book, based essentially on the complexity and phrasing of the words that it uses. They’ve done this by measuring these features for a large number of books, asking people to read the books, measuring how much they understood, and then creating a map from one to the other using standard regression techniques from Statistics. A detailed, though – irony alert! – not very easily readable, description of the analysis is given here.
The end result of this process is a formula which takes the text of a book and converts it into a ‘readability’ score. Mr. Greedy got a score of 4.4, ‘Of Mice and Men’ got 4.5 and ‘The Grapes of Wrath’ got 4.9. The most difficult book in the database was ‘Gulliver’s Travels’, with a score of 13.5. You can check the readability index value – labelled BL for ‘Book Level’ – for any book in the database by using this dialog search box.
So, yes, Mr. Greedy is almost as complex a piece of literature as the Steinbeck classics.
But… there’s a catch, of course. Any statistical analysis is limited to its own terms of reference, which in this case means that comprehension is measured in a strictly literal sense; not comprehension in a narrative sense. In other words, no attempt was made to assess whether readers understood the sum total in a literary sense of what they were reading, just the individual words and sentences. As such, the values 4.4, 4.5 or anything else say nothing about how difficult a book is to read in terms of narrative comprehension. Sure, the words and sentence structure of Mr. Greedy and The Grapes of Wrath are of similar complexity, but having understood the words in both, understanding the full meaning of Mr. Greedy is likely to be an easier task.
Does this have any relevance at all to sports modelling? Admittedly, not much. Except, it’s always important to understand what has, and has not, been included in a sports model. For example, in a football model based only on goals, when using predictions, it’s relevant to consider making adjustments if you are aware that a team has been especially unlucky in previous games (hit the post; marginal offside; etc etc). But if the model itself already included data of this type in its formulation, then it’s likely to be incorrect to make further adjustments, as doing so would be to double-count the effects.
In summary, if you are using a statistical model or analysis, make sure you know what it includes so as to avoid double-counting in sports models, or buying your 2 year-old nephew a Pulitzer prize winning American masterpiece for their birthday.