stats tests Flashcards
What are the three factors used to decide which statistical test to use?
- Level of measurement
- Wether the researcher is looking for a difference or a correlation.
- (If it’s a difference- which experimental design is being used).
What are the three levels of measurement?
Nominal
Ordinal
Interval
What is nominal data?
Data represented in the form of categories.
What is a feature of nominal data?
Nominal data is discrete as only one item can appear in one of the categories.
What is ordinal data?
Data that is ordered in some way but does not have equal intervals.
Give an example of ordinal data.
A scale of 1 to 10.
What is a feature of ordinal data?
It is subjective as it takes into account people’s opinions so it can be considered to lack precision.
What is interval data?
Data on a measurement scale which has equal intervals.
Give an example of interval data.
Things used to take measurements on such as thermometer, stopwatches or weighing scales.
Give a feature of interval data.
Interval data is precise and sophisticated.
How do we work out if a researcher is looking for a difference or a correlation?
It will usually be clear from the wording of the hypothesis. E.g relationship= correlation but difference= difference.
What are the three types of experimental design?
Independent groups
Repeated measures
Matched pairs
Which types of experimental design are considered ‘related’?
Repeated measures
Matched pairs
Which types of experimental design are considered ‘unrelated’?
Independent groups.
Why are repeated measures and matched pairs considered as related?
In a repeated measures design, the SAME participants are used in all conditions. In matched pairs, participants have been matched based on the SAME variable.
Why is independent groups considered to be unrelated?
The participants in each condition are different.
What are the three tests of correlation?
-Chi-squared
-Spearman’s rho
-Pearson’s r
What are the 6 tests of difference?
-Chi-sqared
-Mann-Whitney
-Unrelated t-test
-Sign test
-Wilcoxon
-Related t-test
Which test is used for nominal, unrelated data?
Chi-squared
Which test is used for ordinal,unrelated data?
Mann-Whitney
Which test is used for interval, unrelated data?
Unrelated t-test
Which test is used for nominal, related data?
Sign test
Which test is used for ordinal, related data?
Wilcoxon
Which test is used for interval, related data?
Related t-test
