inferential statistical tests

Question 1

what is the first step in stats tests?

Answer 1

● writing a null hypothesis (where there is no relationship between the 2 variables - any perceived relationship is due to chance)

Question 2

chi squared test

Answer 2

● used when data is categorical

● looks for differences between observed (what you see) and expected data(what it would be if null hypothesis was true)

● e.g. do different species prefer a different habitat

Question 3

spearman’s rank (correlation coefficient)

Answer 3

● used when examining an association between 2 sets of data

● -1 = negative correlation

● 0 = no correlation

● +1 = positive correlation

● e.g. how does snake length effect snake body mass

Question 4

student t test

Answer 4

● used when comparing the mean value of 2 sets (2 means) of data

● e.g. is there a difference between mean mass of 2 different populations of gorillas