Sign test

State the Hypothesis (directional hypothesis requires a one tailed test and non-directional requires a 2 tailed test)

for each pair of data add a sign column (+ or -) depending on which item in the pair is greater. if no difference then leave blank

inferential statistics do not account for sample bias

find the calculated value of the test statistic (S) which is the frequency of the less frequent sign (either + or -)

find the critical value of S from the table of critical values; where N = total number of scores (ignoring blank rows) and choosing a one or two tailed test and a level of significance (either 0.05 or 0.01).

compare the calculated value with the critical value; following the instructions below the table to see whether the difference is significant and if the hypothesis can be accepted

calculated value must be equal or less than critical value to be significant.

Sign test is test of difference

Repeated measures design

Nominal Data