Psychology by the numbers
Psychology would seem, at first look, to be one of the sciences with the least involvement with mathematics. After all, psychology is all about the mind, all about people – what does mathematics have to do with that?
Well, as it turns out, a lot! The main reason is that mathematics is of use, is that psychology has one aspect that most people don’t consider. Most think of psychology as relating to a single person, but there is one other consideration. We also care about how groups respond, and how the individual compares to the group.
To this end, we need a simple way to describe groups, so we can compare them to each other and to the individual. The best way to do this reliably is to use mathematics – and we are interested in two particular concepts – the idea of what the average value of a group is, and the idea of how much the group is distributed.
In this post, I will cover the basic mathematics you will need to describe these concepts – which you will need for your Empirical Research Activity (ERA) report that is due at the end of term 4. The mathematics is *not* difficult, and you will be able to the majority of it on your computer, by using microsoft excel (or a similar piece of software).
So, let’s hit the concepts then. Here they are, with the formal language we use to describe them:
1. Measures of Central Tendency: otherwise known as the average, there are three possible choices: Mean, Median & Mode. We are most interested in the mean. You are probably familiar with these from Maths in years 8 and 9.
2. Measures of Spread: these are probably newer to you, but you may have done them recently. The ones we are interested in are Interquartile range and standard deviation.
The first thing you need to do is access the file with the results from our Perceptions of Mental Health survey. They are stored on a google drive accessible to you with your Melba Login. Here is the link: ERA Files.
The mathematics and techniques of calculating the average (“mean”) and spread (“standard deviation”) are covered in this video.
I will explain more after I know some of you have read this far, and watched the video, I will update this post with more information after six students have commented on this post. It’ll be interesting to see who comments, and how long it takes…
I hope you’re enjoying your holidays and making progress on your folio project.