A survey of TV watching habits is conducted with the following results
This reference flowchart is one of a series of three, designed by Stella Dudzic.
The series includes: Hypothesis tests for one sample, Hypothesis tests for two samples, and
Experimental Design and Hypothesis tests for several samples: ANOVA (Analysis of Variance)
The series is also available as a set of three full colour posters in A2 size for wall display.
To view the colour posters and to place an order please visit the MEI website at
www.mei.org.uk
Number of hours of TV watched per week
Does this provide evidence that
Sample size
Sample mean
Sample variance
there is a difference in the
Women
50
11.2
135.2
mean number of hours of TV
Men
60
9.6
66.9
watched by men and women?
Do you know
the variance
of the
differences?
Yes
Test on
difference of
means/medians
Do you
have large
samples?
Yes
No
Matched
(paired)
samples
Are the
differences
Normally
distributed?
Unpaired
samples
No
Testing whether
they are from
the same
distribution
Do yo u
have large
samples?
No
Are the data
from Normal
distributions?
No
This reference flowchart is one of a series of three, designed by Stella Dudzic.
The series includes: Hypothesis tests for one sample, Hypothesis tests for two samples, and
Experimental Design and Hypothesis tests for several samples: ANOVA (Analysis of Variance)
The series is also available as a set of three full colour posters in A2 size for wall display.
To view the colour posters and to place an order please visit the MEI website at
www.mei.org.uk
Are the
differences
sym metrically
distributed?
Do you
know
the
variances?
Yes
Test on
difference
of variances
No
Estimate variance of differences
using s² and use Normal test
Yes
Normal test
No
Estimate variance of differences
using s² and use t test
Wilcoxon paired
sample test
No
Sign test
Kolmogorov-Smirnov 2-sample test
Yes
Test on difference
of means/medians
Normal test
Yes
To do a test
on paired samples, first find the
differences between paired data
values and then proceed as for
a single sample test
Are your
samples
matched?
Do you know
the variance
of the
differences?
Yes
Do you
know
the
variances?
Are the data
from distribu
tions
with the same
shape?
Yes
Normal test
No
Estimate variances using
s²,s² and use Normal test
Yes
Normal test
Yes
No
Are the
variances
equal?
t test with pooled
estimate of variance
No
No suitable simple test
Yes
Wilcoxon rank sum test
or Mann Whitney U test
No
No suitable simple test
F test