So this week I decided to do quite a simple blog, but on a topic that I’ve always struggled to get into my brain. Every experiment and every piece of research talks about variables in varying terminology yet is always something that confuses me each time I read about them. Obviously I understand the dependent and the independent variable. However, when reading through my Andy Field book (having a particularly nerdy moment, it has to be said that these are rare) I’ve come across different types of variables that I’ve never really heard of before.

A binary variable- there are only two categories, for example; yes or no.

It has to be said, that the following I have actually heard of, but I always get confused between which ones should be applied to which research. I’ve included these in my blog in the hope that others like me, who may get slightly more confused than the average population will be able to gain a greater understanding.

A nominal variable- there are more than two categories

Ordinal variable- these are the same as a nominal variable but they have a logical order

Interval variable- equal intervals on the variable represent equal differences in the property being measured

Ratio variable- the same as an interval variable, but the ratios of score on the scale must also make sense.

Variables can also be split into continuous and categorical; binary, nominal and ordinal are all categorical whereas interval and ratio are continuous.

Continuous means that the entities get a distinct score and categorical means that the entities are divided into distinct categories.

So, hopefully after reading this you’ll have gained more of an insight into the wonderful topic of variables.. or just revised something you may have already known. For those of you who may want to read more about variables then its all in Andy Fields ‘Discovering Statistics Using SPSS’ book, or have a look at this website http://www.socialresearchmethods.net/kb/variable.php which explains things quite well too 🙂