exam 2 Flashcards
(23 cards)
mean
average
sum/size
interval and ratio
median
middle
interval and ratio
mode
most
nominal and ordinal
range
y max - y min
describes the extremes of the data around the typical case
variance
x = samples
x bar = mean
x - x bar
x - bar ^2
total / n-1 = variance
takes into account all variables
SD
sq rt of variance
summarizes the data more than the variance bc SD is in the same unit as the mean
says if something is unexpected
bell curve
hypothesis testing
compare means of 2 groups
n =
sample size
x bar =
sample mean
u =
population mean
s =
sample SD
o =
population SD
a =
level of confidence
degrees of freedom =
sample size - 1
z test =
population
t test =
sample (n-1)
central tendency
describes the typical case in a data set
mean
median
mode
dispersion
if there is no variability, all measures will be 0
Nominal/ordinal - nominal/ordinal =
cross tabs ch. Sq tests
interval/ratio - nominal-ordinal =
regression
interval/ration- interval/ratio =
scatterplots, regression
nominal/ordinal - interval/ratio =
box plots, dif. Means. tests
Chisquare =
sum of the squared difference between observed and expected frequencies in each cell/expected frequency for each cell
The chi-square test is a hypothesis test designed to test for a statistically significant relationship between nominal and ordinal variables organized in a bivariate table. In other words, it tells us whether two variables are independent of one another.
