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Section 4.1. How Can We Describe the Relationship between two sets of Quantitative Data?. Consider the Relationship Between Length and Weight in some Lengths of Channel Iron:. Scatter Plot. Correlation Coefficient. Here is how to do it by hand:. Compute
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Section 4.1 How Can We Describe the Relationship between two sets of Quantitative Data?
Consider the Relationship Between Length and Weight in some Lengths of Channel Iron:
Correlation Coefficient • Here is how to do it by hand: • Compute • Determine for each observation • Compute for each observation • Determine • Divide the sum by n-1
Channel Iron Correlation: • = 35.8 & Sx = 15.1888 • = 319.6 & Sy= 151.4754 • Correlation Coefficient is r = .998 … strong correlation!!! r = = .998
Temp/Elevation Correlation: • Calculate the Correlation Coefficient • r = -.951 • What does the negative value reveal about the data?
Temp/Elevation Correlation: • Let’s get the TI – 84 to do all this tedious work for us • Web link to a good graphing calculator regression: • http://www.youtube.com/watch?v=nw6GOUtC2jY