Chapter 3notes

Chapter 3notes - Review of Chapter 2 Range: one measure of...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Review of Chapter 2 Range : one measure of variability Not used to calculate the variance Calculating mean : (aka “the average”) the fulcrum around which all the other scores balance
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Review of Chapter 2 Calculating the variance: 1. find the mean 2. subtract the mean from each score This is the deviation score 3. Square the deviation score 4. Add the squared deviation scores This is the Sums of Squares 5. Divide the Sums of Squares by n-1 “n” = the number of participants **The range is not needed for these calculations
Background image of page 2
Standard Deviation *Not mentioned in Chapter 2* Standard Deviation : the square root of the variance If the mean and standard deviation of a normal distribution are known it is possible to compute the percentile rank associated with any given score. In a normal distribution, about 68% of the scores are within one standard deviation of the mean and about 95% of the scores are within two standards deviations of the mean
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Calculating Variance and the Standard Deviation Participant Score Deviation Score Squared Deviation 1 4 4-5.6=1.6 1.6^2=2.56 2 5 5-5.6=-.6 -.6^2=.36 3 9 9-5.6=3.4 3.4^2=11.56 4 10 10-5.6=4.4 4.4^2=19.36 5 0 0-5.6=-5.6 -5.6^2=31.36 Mean=5.6
Background image of page 4
Calculating Variance and the Standard Deviation Sum of Deviation score 2.56 .36 11.56 19.36 + 31.36
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/30/2008 for the course PSYC 2094 taught by Professor Trcunningham during the Fall '07 term at Virginia Tech.

Page1 / 21

Chapter 3notes - Review of Chapter 2 Range: one measure of...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online