data analysis part 3 inferential/statistical tests and probability Flashcards
what is the point of a significance level
the confidence of which the alternative or null hypothesis can be accepted
what is the significance level used in psychology
0.05 or 5%. this means there is a 95% the results are experimentally significant, and it strikes a balance between making a type i or ii error a researcher can not be 100% sure of this as it means testing every single member of the population in every possible circumstance
what are statistical tests used for
they determine whether the result of an experiment is significant. if a difference is found between the scores of two groups then it may be because of the tested difference but it might actually be due to chance factors instead
what is a statistically significant result
the result is highly likely to have happened due to the IV so it is therefore statistically significant
what do researchers use when researching a sensitive topic
they use a stricter level of measurement, like 1% or 0.01 to be even more sure they have signifcant results
what is the nominal level of measurement
it is used for categorical variables such as assigning whether a person is female or male
what is the ordinal level of measurement
assigning scores so they represent the rank order of the individual - rating variables
what is the interval level of measurement
assigning scores using numerical scales where intervals have same interpretation throughout such as temperature
what is the rule for statistical test with r in its name
significance level should be equal or greater than to its critical value
whats a type i error
alternative/experimental hypothesis mistakenly accepted so null is rejected. researcher says there is a significant difference between the groups when there isnt. chance = 5% due to conventional significance being 0.05
whats a type ii error
null hypothesis mistakenly accepted, alternative rejected. happens when signifcance level too strict like 1%
What are the eight statistical tests in psychology
The Chi Squared test
The Sign test
Mann-Whitney test
Wilcoxon test
Spearman’s Rho
Pearson’s r
Related t-test
Unrelated t-test
pnemonic for tests
Simon (sign) Cowell (Chi) Wants (Wilcoxon) More (Mann-Whitney) Singers (Spearman’s) Receiving (Related -t) Unanimous (Unrelated-t) Praise (Pearson’s)
describe structure of table
top of table = test of difference, underneath test of difference is related design and unrelated design
on right side is test of association
on the side it goes from nominal, ordinal, interval
