Sign Test

• What are the 3 reasons for using a sign test?

  1. You're looking for a difference
  2. The design is either matched pairs or repeated measures
  3. The data is nominal or has been converted to nominal data
• How to carry out a sign test?

  1. Calculate the difference between condition A and B
  2. Put the sign in the final column (+/-)
  3. Add up the number of time the less frequent sign occurs - obtained value 's'
  4. Find the critical value from the table given
  5. Compare 's' value with the critical value - 's' must be less than or equal to the critical value
  6. Statement of significance