inferential tests

• calculate sign test by:

  1. enter pairs of related data in a table
  2. for each pair, score + or - (+ if item is smaller than 1, - if item is bigger than 1)
  3. S = number of less frequent sign (+ or -)
  4. compare calculated values with critical value
• calculate degrees of freedom for unrelated t-test by:

  df= Na + Nb - 2
• calculate degrees of freedom for related t-test by:

  df = N - 1