So Many Numbers - Harry Potter and the Token Black Guy

June 12, 2011

Is Dean Thomas the "token black guy."

This image intrigued me slightly. Obviously, to look at it it seems like Dean Thomas is indeed a “token black guy”, who was just inserted into the story to make a story about middle-class white kids a bit more politically correct. I wanted to find out whether this was the case; in other words, whether it would have been likely for there to have been one black guy in Dumbledore’s Army.

To start with, I worked out the percentage of Afro-Caribbean people in Britain at the approximate time that Harry Potter is set. The books take place throughout the 1990’s, so I took my figures from 1991 (although Order of the Phoenix is set in 1995, figures for ‘95 are less easy to find.)

In 1991, there were roughly 500,000 Afro-Caribbean people in Britain, out of an overall population of 57,808,000. This means that Afro-Caribbean people made up 0.8649% of Britain.

Okay, here’s where the real maths starts.

Let X be the number of members of Dumbledore’s Army who are black. There are a total of 15 members in the above picture, so:

X ~ Bin(15, 0.008649)

So, the probability that there would be one Afro-Caribbean student in the Army is:

P(X=1) = ¹⁵C₁ × 0.008649¹ × (1-0.008649)¹⁴

= 0.1148792105

= 11.5% (1 d.p.)

Assuming a 5% level of significance (i.e. we would only consider it unlikely if P(X=1) was less than 5%, which is the norm), there is no reason to assume that a group of 15 Hogwarts students would not contain anyone of Afro-Caribbean origin.

Obviously, to reach this result I’ve had to make a couple of assumptions, namely:

The ethnic distribution of Hogwarts students is more or less the same as Britain as a whole (i.e. magical ability is spread evenly between ethnicities.)
The ethnicity of members of Dumbledore’s Army is random (to not assume this would be to suggest that morality and/or bravery varies by ethnicity, so I think this is a safe assumption to make.)

But overall, I think it’s reasonably safe to conclude that Dean Thomas was not necessarily levered into Dumbledore’s Army in an attempt to represent all ethnic minorities. Although, with a reasonable knowledge of today’s media, it’s also entirely possible that he was. :P

Yes, I’m fully aware that the original image was a joke, it just sparked a certain curiosity which I wanted to satisfy.

Have I made a mistake? Tell me, I’ll be happy(ish) to admit I was wrong. :P

If you have any suggestions for future posts similar to this, please feel free to ask. :)

8:53pm | URL: http://tmblr.co/Z4KBNx61DT-j

(Notes: 5)