parametric tests: unrelated and related t-test

• to interpret the unrelated and related t-test

  1. calculated value will always be given to you
  2. hypothesis (one tailed or two tailed)
  3. experimental design
  4. critical values table (given to you)
  5. level of significance (given to you, if not assume its 0.05)
  6. no. of participants (found on the stem)
  7. formula to calculate df (given to you)
• unrelated: df = Na + Nb - 2 


  related: df = N - 1
• results are not significant if the calculated value is lower than the critical value

  H1 alternative hypothesis has to be rejected

  so H0 null hypothesis has to be accepted
• results are significant if the calculated value is higher than the critical value

  H1 alternative hypothesis can be accepted

  so H0 null hypothesis can be rejected
• when answering a question, apply your conclusion to the scenario

  e.g we can conclude that participants had significantly higher stress levels when holding a real snake compared to a toy snake