Sign test

• When to use a sign test

  Used for a test of difference

  • Nominal data
  • Related design so repeated measures or matched pairs in the experiment
• Step 1

  Work out the difference between 2 sets of data in the graph

  Subtract the column

  No difference is 0 and is ignored

  Find the least occuring sign

  S is the least occuring sign this is the calculated value

  N VALUE IS NUMBER OF PARTICIPANTS NOT INCLUDING 0 VALUES

  COMPARE CALCULATED VALUE TO CRITICAL VALUE
• Is the test one tailed or two tailed

  What is the significant level (0.05)

  How many participants are they? N VALUE

  This gives a critical values

  The calculated value S must be equal to or less than the critical value in order to be significant