Statistical Analysis Flashcards
(16 cards)
What is normal distribution?
Data that has the same mean, mode and median with symmetry about the centre.
What is nominal data?
Frequency/count data that consists of the number of participants falling into categories.
What is ordinal data?
Data that is presented in rank order.
What is interval data?
Data that has a set difference between all values on a scale.
What is positive and negative skewed data?
Positively skewed data:the mean is greater than the median
Negatively skewed data: the mean is less than the median
What do inferential statistics tell us?
Tells us whether or not it is safe so say that the results from the investigation are valid.
What are the levels of significance?
95%(0.05) vs 99% 90.01)
(Always look for 0.05 on the tables first).
What is one tailed and two tailed meaning?
One tailed (directional)-predicts a specific outcome.
-one condition is better/worse than the other
Two tailed (non-directional)-a difference is predicted, but not specific
Statistical analysis table
Independent measures. Repeated measured. Association/correlation
Nominal. Chi-squared. Binominal sign squared. Chi-squared
Ordinal Mann-Whitney u. Wilcoxon signed-rank test. Spearman’s rho
What are type 1 and type 2 errors?
Type 1 error-false negative
-saying there is a difference but there isn’t
Type 2 error-false positive
-saying there is a difference but accepting the null
Under what 2 circumstances would you use a Wilcoxon test?
Repeated measures.
Ordinal data.
What are the 3 levels of measurement?
Nominal, ordinal, interval.
What does standard deviation measure?
Distance of data between the means.
Measure of dispersion- range.
Why would you use a Mann-Whitney u test?
An experiment, ordinal data and independent measures.
When would you use a spearman’s rank test?
Correlational data
Ordinal data
When would you use are chi-squared test?
Nominal data, correlation.
