Statistical tests

• the correlation coeffecient is just r value which you have learned from maths
• PMCC, the correlation coefficient is the best test for looking at the strength of a relationship between 2 variables
• spearmans rank cc is very similar to r value and you will be given the formula to calculate it.

  this is the one that appears in tests so if you want to test the relationship and strength between variables you would use this.
• t values are used to compare the means of related and independent date sets.

  a t value of 0 means the means are the same

  the t test is not used if there are outliers or skews
• the t test used for related variables is the paired student's t test
• the t test used for independent variables is the unpaired student's t test
• The chi-squared test is used to measure the variance between observed and expected results
• When is the T test appropriate to use?

  When testing for the difference between two means(independent variables).