Statistical testing

• What is the purpose of statistical testing?

  To determine if data differences are significant
• What does a significance difference indicate?

  It is greater than chance occurrence
• What do critical values indicate?

  Thresholds for determining significance
• What information is needed to find the critical value?

  Significance level, N value, hypothesis type
• What does the significance level usually equal?

  0.05 or 5%
• What is the difference between directional and non-directional hypotheses?

  Directional specifies the expected outcome
• What is the first step in calculating the sign test?

  Subtract condition B score from condition A
• What should be calculated after finding the sign of difference?

  Total number of pluses and minuses
• What does the S value represent in the sign test?

  Total of the less frequent sign
• What are the steps involved in the sign test calculation?

  1. Subtract condition B from condition A
  2. Calculate total pluses and minuses
  3. Disregard participants with same scores
  4. Determine S value from less frequent sign
  5. Compare S with critical value for significance