Use of Sign Test

• What is the purpose of statistical testing?

  To determine whether hypotheses should be rejected or accepted
• What does statistical testing help identify in experiments?

  Whether differences or relationships between variables are statistically significant
• What is an example of a statistical test mentioned in the material?

  The sign test
• What are the conditions for using a sign test?

  • Look for a difference, not an association
  • Use a related experimental design (repeated measures)
  • Collect nominal data
• What is the first step in conducting a sign test?

  State the hypotheses, including both the alternative and null hypothesis
• How do you determine the sign in a sign test?

  The sign is negative (-) if the value decreased and positive (+) if it increased
• What should you do if a value stays the same in a sign test?

  Ignore that value and adjust N to exclude it
• What does S represent in the sign test?

  S is the number of times the less frequent sign occurs
• How do you find the critical value of S?

  Use the calculated N value and p = 0.05
• What does it mean if S is less than the critical value?

  Reject the null hypothesis; there is a significant difference
• What should you conclude if S is greater than or equal to the critical value?

  Accept the null hypothesis; there is no significant difference
• What should be included in the conclusion of a sign test?

  Refer back to the hypothesis and mention the IV, DV, and exact values of critical value, S, N, and p value