Casio Fx-991ES PLUS Statistics: Standard Deviation, Normal Distribution and Regression

NOTE: the normalised variate t does not need to be divided by x (someone in the comments helpfully pointed this out). It turns out that the calculator manual got this formula wrong and I stupidly repeated it in the video - sorry about that.

In this video we are going to take an in-depth look at the statistics functions that are built into your Casio FX-991 ES Plus Calculator. We will look first at single variable statistics (mode 3 1) which can be used to do summations and find the mean and standard deviation of a sample.

We will then look at the normal (Gaussian) distribution function which will let us calculate P(t), Q(t), R(t) and, of course the normalised function t itself.

Finally I will show you how to find Pearson's r (with a little background theory) and do a linear regression calculation. The calculator is able to do other regression calculations such as logarithmic and exponential regressions and this works in much the same way as linear regression but uses one of the other modes.