a. Determine the slope (?1) and the y-intercept (?0). b. Formulate the estimated simple linear regression equation. c. Illustrate the regression line using a graph.
Inverse Normal Distribution
The method used for finding the corresponding z-critical value in a normal distribution using the known probability is said to be an inverse normal distribution. The inverse normal distribution is a continuous probability distribution with a family of two parameters.
Mean, Median, Mode
It is a descriptive summary of a data set. It can be defined by using some of the measures. The central tendencies do not provide information regarding individual data from the dataset. However, they give a summary of the data set. The central tendency or measure of central tendency is a central or typical value for a probability distribution.
Z-Scores
A z-score is a unit of measurement used in statistics to describe the position of a raw score in terms of its distance from the mean, measured with reference to standard deviation from the mean. Z-scores are useful in statistics because they allow comparison between two scores that belong to different normal distributions.
The marketing manager of a supermarket chain would like to determine the effect of shelf space
on the sales of pet food. A random sample of 10 stores was selected, and the results are presented
below.
| Store | shelf space in cm | weekly sales in thousand pesos |
| 1 | 45 | 18 |
| 2 | 45 | 21 |
| 3 | 75 | 15 |
| 4 | 80 | 18 |
| 5 | 95 | 23 |
| 6 | 100 | 26 |
| 7 | 135 | 22 |
| 8 | 140 | 27 |
| 9 | 185 | 25 |
| 10 | 190 | 28 |
a. Determine the slope (?1) and the y-intercept (?0).
b. Formulate the estimated simple linear regression equation.
c. Illustrate the regression line using a graph.
d. Using the estimated simple linear regression equation, estimate the weekly sales when the
shelf space is 230cm? 250cm?
e. Compute the coefficient of determination and interpret its value.
Step by step
Solved in 3 steps with 1 images
