Descriptive Stats/Hypothesis Testing

measures of central tendency

estimate of performance - mean, median, mode

measures of variability

how reliable that estimate is - sum of squares, variance, SD, range, standard error

inferential statistics

draw conclusions about irregularities, make inferences about population and test hypotheses

Z score

how many SD score is away from a mean

Z tests

if the difference between 2 means is statistically significant

T tests

use when population mean Is known but SD is not known

hypothesis testing steps

formulate hypotheses, choose statistical test and significance level, collect and analyse data, interpret results, draw conclusions

modality

no. of peaks - unimodal, bimodal, rectangular

skew

symmetry of tails around distribution - positive or negative

kurtosis

peakedness/tailedness

platykurtic (flat with thinner tail)

leptokurtic (peaked with heavier tail)

single sample

compare mean of sample to known/hypothesized population mean

repeated measures t test

compare means of 2 related groups

independent groups t test

compare means of 2 independent groups