Testing Proportions - Week 9 Pt 2 Flashcards
When can chi squared be used?
When one nominal variable with 2+ categories present
(Compare observed freq and expected freq)
Hypothesis in one nominal variables
H0= No inconsistency between observed/expected frequency (same distribution)
H1= Inconsistency between observed/expected frequency (don’t follow same distribution)
What are proportions measured through?
Effect Sizes
How can sample data be analysed to reflect preference in populations?
Through CIs
DF for proportion significant testing
Number of categories - 1
How can CIs be used for significance?
If overlap by 50% = non-significant
Hypothesis for chi squared using two nominal variables
H0= relative proportion of 1 variable are independent to second variable
H1= Relative proportions of 1 variable aren’t independent of second variable
What is a p-value of 0.00 reported as?
p < .001
When are chi-squared tests unreliable?
When any expected frequency is <5
(Especially if num of categories is small)
How can we test proportions and statistical power?
Sample size and effect size = positive relationship
Large bias easier to detect than small bias
Larger N easier to detect than small N