LESSON: Further Interpreting of Z-Scores and the Normal Distribution
| Site: | Mountain Heights Academy OER |
| Course: | Introductory Statistics Q2 |
| Book: | LESSON: Further Interpreting of Z-Scores and the Normal Distribution |
| Printed by: | Guest user |
| Date: | Friday, 4 April 2025, 11:54 AM |
Finding Percentiles
What does "percentile" mean? A percentile is a measure that indicates the value below which a given percentage of observations falls.
For example, if I told you that you scored in the 60th percentile on your ACT test, that would mean that 60% of people who took the test scored less than you. Another way of interpreting this percentile would be that you scored in the top 40% of people who took the ACT.
In this lesson video you will learn how to use the standard normal distribution curve to find percentiles.
Finding Data Points from Z-Scores
In this lesson video you'll see how we can work backwards when given a z-score to find the actual data point the z-score represents. As long as we know the mean and the standard deviation for the data set, then we're good to go!
Identifying Unusual Z-Scores
How do we determine if a z-score is interesting, unusual or atypical? In this lesson video you will learn the rule we follow for identifying unusual data points.
(PS. Please ignore his Wookie voice at the beginning. I promise he is a credible source!)