Stats tests - psych

• Binomial sign test


  1. Give a (+) if condition B is greater than A

  2. Give a (-) if condition A is greater than B

  3. Add up the less frequent sign (s value)

  4. Add up the no. of participants who scored (n value)
• Critical value


  The value used to determine statistical significance in the binomial sign test
• Chi-squared test


  1. Calculate the totals

  2. Calculate the expected frequency (Row total x column total / overall total)

  3. Calculate (O-E)^2/E

  4. Add up the totals to get the chi-square value
• Chi-squared test


  • degree of freedom (no. of rows -1)x(no. of column -1)
  • The critical value is compared to the calculated chi-square value to determine statistical significance
• Mann-Whitney U test


  1. n=no. of ps

  2. Work out U for A

  3. Work out U for B

  4. Add up the smallest U value
• Formula for Mann-Whitney U


  U = n1n2 + n1(n1+1)/2 - R1
• Spearman's rank correlation


  1. Rank the scores

  2. Calculate the difference (d)

  3. Square the differences (d^2)

  4. Add up d2 =to get Ed2. Use the formula: rho = 1 - 6Σd^2 / (n(n^2-1))
• Rule of R - if a test has an R in the name then the significance must be gReater than or equal to
• Wilcoxon signed-rank test


  1. Calculate the difference (A-B)

  2. Rank the scores (ignoring 0s)

  3. Count the ranks associated with the less frequent sign (call this T)

  4. W = the no. of ps - those that scored the same