Presentation on theme: "Quantitative assessment of the strength of the relationship between x & y. It is the measure of the extent to which x & y are linearly related. *It is."— Presentation transcript:
Quantitative assessment of the strength of the relationship between x & y. It is the measure of the extent to which x & y are linearly related. *It is strong if the points lie close to a straight lint and is weak if they are widely scattered about a line.
It’s a number between -1 and 1. The closer it is to the ends, the stronger the positive or negative relationship. It gives the strength and direction. 0 1 Strong Positive No Correlation Strong Negative
If you are asked to interpret a correlation start by looking at a scatterplot of the data. Then be sure to address direction, form, strength, and outliers and put your answer in context.
It does not depend on the unit of measurement. It doesn’t depend upon which of the 2 variables is “x” It’s between -1 and 1 It equals -1 or 1 if all points lie on a straight line It is strongly affected by a few outliers
Scatterplots show relationships – not cause and effect.
Create scatterplot Find the correlation Describe the association Fat (g)Sodium 29920 311150 341200 351095 391180 391120 431260