In: Statistics and Probability
Consider the following sample data for the relationship between advertising budget and sales for Product A:
Observation | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
---|---|---|---|---|---|---|---|---|---|---|
Advertising ($) | 50,000 | 60,000 | 60,000 | 70,000 | 70,000 | 80,000 | 90,000 | 90,000 | 100,000 | 110,000 |
Sales ($) | 299,001 | 371,000 | 364,000 | 430,000 | 440,000 | 485,000 | 535,000 | 546,000 | 595,000 | 675,000 |
What is the correlation value for the relationship between advertising and sales?
Please round your answer to the nearest hundredth.
Solution:
X Values
∑ = 780000
Mean = 78000
∑(X - Mx)2 = SSx =
3360000000
Y Values
∑ = 4740001
Mean = 474000.1
∑(Y - My)2 = SSy =
120493650000.9
X and Y Combined
N = 10
∑(X - Mx)(Y - My) = 20069972000
R Calculation
r = ∑((X - My)(Y - Mx)) /
√((SSx)(SSy))
r = 20069972000 / √((3360000000)(120493650000.9)) = 0.998