The data set shown below gives the calories and salt content in 17 brands of meat hot
Question:
The data set shown below gives the calories and salt content in 17 brands of meat hot dogs.
Brand | Calories | Sodium (mg) |
---|---|---|
1 | 173 | 458 |
2 | 191 | 506 |
3 | 182 | 473 |
4 | 190 | 545 |
5 | 172 | 496 |
6 | 147 | 360 |
7 | 146 | 387 |
8 | 139 | 386 |
9 | 175 | 507 |
10 | 136 | 393 |
11 | 179 | 405 |
12 | 153 | 372 |
13 | 107 | 144 |
14 | 195 | 511 |
15 | 135 | 405 |
16 | 140 | 428 |
17 | 138 | 339 |
a. Enter the data set into Excel. Using Excel, perform a least-squares regression on the data set. Use Sodium as the y variable and Calories as the x variable. Make a scatter plot with the regression line plotted as well. Using Excel, compute the correlation coefficient.
b. Discuss the scatter plot and regression line. Are there outliers? Does your correlation coefficient support your analysis? Does it tell you anything else?
c. If there is an outlier, remove the outlier from the data set and repeat the previous two parts.
d. Can you conclude that hot dogs with more calories will have more sodium (i.e. discuss correlation and causation)?
The outliers affect the amount of correlation between the dependent and the independent variables and they could also decrease the overall standard error of the model.
Stats Data and Models
ISBN: 978-0321986498
4th edition
Authors: Richard D. De Veaux, Paul D. Velleman, David E. Bock