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Correlation. Statistic that describes the relationship between scores (Pearson r).Number is the correlation coefficient.Ranges between 1.00 and 1.00.Positive is direct relationship.Negative is inverse relationship..00 is no relationship.Does not mean cause and effect.Measured by a Z score.
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1. Correlation, Reliability and Regression Chapter 7
2. Correlation Statistic that describes the relationship between scores (Pearson r).
Number is the correlation coefficient.
Ranges between +1.00 and 1.00.
Positive is direct relationship.
Negative is inverse relationship.
.00 is no relationship.
Does not mean cause and effect.
Measured by a Z score.
Generally looking for scores greater than .5
3. Reliability Statistic used to determine repeatability
Number ranges between 0 and 1
Always positive
Closer to one is greater reliability
Closer to 0 is less reliability
Generally looking for values greater than .8
4. Scattergram or Scatterplot Designate one variable X and one Y.
Draw and label axes.
Lowest scores are bottom left.
Plot each pair of scores.
Positive means high on both scores.
Negative means high on one and low on the other.
IQ and GPA?
~ 0.68
5. Example (high correlation with systematic bias)