Research Methods - Statistial Tests Flashcards
When do you select a chi squared test
When research is a test of difference or association
The level of measurement is nominal
The test is used with an unrelated design - independent groups
Contingency table normally used
What two values do you need to interpret a chi squared test
A calculated value of x2 (will be already calculated)
And critical value from table
For a chi squared how do you find the critical value
Level of significance
If it is a one tailed (directional hypothesis) or two tailed (non directional )hypothesis
Degrees of freedom : this found by (no of rows -1) x (columns-1)
For the results to be significant in a chi squared what must the calculated test be ?
Needs to be more than or equal to the critical value
How would you write up the results for a chi squared test
As the calculated value of X2 (_______) is greater than the critical value of X2 ______ (P≤0.05, df=_____) the result is significant and we can reject the null hypothesis. There is a difference/ association between __________ and ___________.
“As the calculated value of X2 (_______) is smaller than the critical value of X2 ______ (P≤0.05, df=_____) the result is not significant and we can accept the null hypothesis. There is no difference/ association between __________ and ___________.”
When is a mann Whitney test used for ?
Test is used when looking for a difference
Using an independent groups design
And the data is ordinal
Eg number of things in another thing
Chocolate chips in a cookie
What two things are needed for a Mann Whitney test
Calculated value of U
And critical value of N which means number of participants
How would you use a critical table in Mann Whitney test to see if results are significant
Identify the significance level
Identify if it is one tailed or two tailed test
Identify number of participants
When are the results from a Mann Whitney significant
U value must be equal to or less than the critical value of U found in the critical value table for the test to be significant.
How would you write out the results from a Mann Whitney test
As the calculated value of U (____) is less than or equal to critical value of U (____) (N= ____ p ≤ 0.05) the result is significant and we must reject the null hypothesis. There is a difference between ______ and ________.’
• ‘As the calculated value of U (____) is more than the critical value of U (____) (N= ____ p ≤ 0.05) the result is not significant and we must accept the null hypothesis. There is no difference between ______ and ________.’
When is a wilcoxon test used for
When looking for a difference using a repeated measures design
The level of measurement required is ordinal
What two things do you need to use a wilcoxon test
Calculated value of T
And critical value of T using N
For a wilcoxon test how do you find the critical value of T from the critical value table
Identify if it is one tailed or two tailed hypothesis
Significance level used in the study
Number of participants (this will be the same for each condition or group as design is related )
For the results from a wilcoxon test how do we know if the results are significant
If the value of t calculated from the statistical test is equal to or less than the critical value of T found in the critical value table to be significant
How do we report the results of wilcoxon test
As the calculated value of T (____) is less than or equal to critical value of T (____) (N= ____ p ≤ 0.05) the result is significant and we must reject the null hypothesis. There is a difference between ______ and ________.’
• ‘As the calculated value of T (____) is more than the critical value of T (____) (N= ____ p ≤ 0.05) the result is not significant and we must accept the null hypothesis. There is no difference between ______ and ________.’
