Data Analysis 3
Parametric Inferential Test
You can only use a parametric inferential test if you have ratio or interval data!!
You have three choices of parametric inferential tests: A Dependent T-test, An Independent T-test or A Pearson Product Moment Correlation Test.
You use a dependent T-Test when you want to prove or disprove there is a difference between two related scores. By related scores it could mean comparing the same subjects' scores before and after an intervention. For example, is there a significant difference between subjects' speed performance before taking an energy drink and after taking an energy drink. Another example could be is there a significant difference between your participants' strength scores before a warm up and after a warm up. The similarities between the two examples given are that they have a before and after score from the same participants. If you have this then you can use a dependent t-test!
You use an independent T-Test when you want to prove or disprove there is a difference between two different group's scores. For example males compared to females, Man Utd compared to Fulham FC, Creatine compare to protein. For example, is there a significant difference between the group taking creatine and the group taking protein? Another example could be is there a significant different between the female group's flexibility scores and the male group's flexibility scores. The similarities between the two examples given are that they are comparing different groups!. If you have this then you can use an independent t-test!
PEARSON PRODUCT MOMENT CORRELATION
Used if you are trying to identify a relationship (correlation) between two variables. For example, is there a correlation between number of calories eaten and amount of body fat? Is there a relationship between taking protein shakes and an increase in muscle mass? Is there a relationship/correlation between the number of shots taken by a player and their confidence levels?