math skills Flashcards
what is the standard deviation?
how far on average the data values are from one another
when do you use the chi squared test?
when comparing frequenciues from observed and expected values
when do you use the spearmans rank correlation coefficient?
when checking the relationship between two variables
i.e HR at rest and number of hours of exercise per week
when do we use unpaired t-test?
the difference between the mean of two seperate groups
i.e heart rate between dogs and cats
when do use paired t-test?
difference between the mean of two different measurements of the same group
how to normaly caluclate degrees of freedom?
n-1
how to caluclate degrees of freedom for unpaired t-test?
(n group A - 1) + (n group B - 1)
what happens when the stats test is greater than the critical vaule?
reject null hypothesis
not due to chance
their is a significant difference
what happens when the stats test is lower than the critical vaule?
accept null hypothesis
due to chance
their is not a significant difference
