Calculating a Standard Score

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<h3>Calculating a Standard Score</h3>

Standard score is a statistics term. The standard score shows how far away from the mean a score falls. It is also known as a z-score. Using a z-score table, you can find where the score falls on the table and figure out what percentile the score falls in. This is a way of standardizing tests in order to curve the scores to fit around the mean. If everyone does poorly on a test, the score distribution will curve up to fit around the average score on the test.

Step 1

Find the mean and standard deviation of your data set. For example, assume you have a data set with a mean of 24 and a standard deviation of 5. You want to find the standard score of 28 in the data set.



Step 2

Subtract the mean from the data for which you want a standard score. In the example, 28 minus 24 equals 4.

Step 3

Divide the difference between the data and the mean by the standard deviation. In the example, 4 divided by 5 equals a standard score of 0.8. You can use this score on a z table to see where it falls as a percentage of the rest of the scores.

Things Needed

  • Data set
  • Mean of data set
  • Standard deviation of data set
Dave Pennells

By Dave Pennells

Dave Pennells, MS, has contributed his expertise as a career consultant and training specialist across various fields for over 15 years. At City University of Seattle, he offers personal career counseling and conducts workshops focused on practical job search techniques, resume creation, and interview skills. With a Master of Science in Counseling, Pennells specializes in career consulting, conducting career assessments, guiding career transitions, and providing outplacement services. Her professional experience spans multiple sectors, including banking, retail, airlines, non-profit organizations, and the aerospace industry. Additionally, since 2001, he has been actively involved with the Career Development Association of Australia.