inferential testing Flashcards
what is the signs test nature and use
statistical test of difference that allows a researcher to determine the significance of their investigation. It is used in studies that have used a repeated measures design, where the data collected is nominal.
what is nominal data
Data in categories
how do you calculate using the sign test
- Subtract the ‘exercise before test’ score from the ‘no exercise’ score and add the answer to the ‘difference’ column e.g. …
2.If the score after subtraction is positive, place a + before the number in the ‘difference’ column. …
3.Count the number of + and – signs.
4.Identify the critical value using a statistical table.
what is meant by probability
the likelihood of an event occurring. It can be expressed as a number (0.5) or a percentage (50%). Statistical tests allow psychologists to work out the probability that their results could have occurred by chance, and in general psychologists use a probability level of 0.05.
what is meant by statistically significant
the claim that a result from data generated by testing or experimentation is likely to be attributable to a specific cause.
what are critical values
the value of the test statistic which defines the upper and lower bounds of a confidence interval, or which defines the threshold of statistical significance in a statistical test.
what is a type 1 error
(false-positive) occurs if an investigator rejects a null hypothesis that is actually true in the population
what is a type 2 error
occurs if the investigator fails to reject a null hypothesis that is actually false in the population.
when would you use spearmans RHO test
COS
correlational or ordinal information
when wold you use Pearsons r test
CIP
correlational interval
when would you use the wilcoxin test
WORD
ordinal, repeated measures, differences
when would you use the manwhitney test
MIDO
independent groups, differences, ordinal
when would you use the related T test
DIRRT
difference, interval, repeated measures
when would you use the unrelated t test
UNIITD
interval, independent groups, difference
when would you use the chi-square test
CANDI
association, nominal, difference, independent groups
what is nominal data
data in categories and in rhetoric form of frequencies
what is ordinal data
data which can be ordered and ranked
what is interval data
time, temperature, weight, height
