Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

The local ice cream shop keeps track of how much ice cream they sell versus the

ID: 3198851 • Letter: T

Question

The local ice cream shop keeps track of how much ice cream they sell versus the temperature on that day, here are their figures for the last 4 days:
Ice Cream Sales vs Temperature Temperature (C) | Ice cream Sales 2 | 27 5 | 17 7 | 10 11 | 8
Find the slope of the regression line: The local ice cream shop keeps track of how much ice cream they sell versus the temperature on that day, here are their figures for the last 4 days:
Ice Cream Sales vs Temperature Temperature (C) | Ice cream Sales 2 | 27 5 | 17 7 | 10 11 | 8
Find the slope of the regression line:
Ice Cream Sales vs Temperature Temperature (C) | Ice cream Sales 2 | 27 5 | 17 7 | 10 11 | 8
Find the slope of the regression line:

Explanation / Answer

Result:

The local ice cream shop keeps track of how much ice cream they sell versus the temperature that day. Here are their figures for the last 4 days:

Regression Analysis

0.917

n

4

r

0.958

k

1

Std. Error

38.127

Dep. Var.

sales

ANOVA table

Source

SS

df

MS

F

p-value

Regression

160,218.6163

1  

160,218.6163

110.22

1.02E-06

Residual

14,536.3004

10  

1,453.6300

Total

174,754.9167

11  

Regression output

confidence interval

variables

coefficients

std. error

   t (df=10)

p-value

95% lower

95% upper

Intercept

-159.4742

54.6407

-2.919

.0153

-281.2213

-37.7270

Temp

30.0879

2.8659

10.499

1.02E-06

23.7022

36.4735

Predicted values for: sales

95% Confidence Interval

95% Prediction Interval

Temp

Predicted

lower

upper

lower

upper

Leverage

20

442.2831

416.341

468.225

353.459

531.107

0.093

Predicts sales when Temperature is 20 is 442.2831

Not applicable. We are predicting the sales from temperature not otherway.

The slope of the line tells you that when the temperature increases by 1 , then the sales will increases by 30.0879.

Calculate residual for the point (14.2, 215)

Predicted sales for Temperature 14.2 = -159.4742+30.0879*14.2 =267.77398

Residual =(215-267.77398) =-52.77398

=-52.7740 ( 4 decimals)

Regression Analysis

0.917

n

4

r

0.958

k

1

Std. Error

38.127

Dep. Var.

sales

ANOVA table

Source

SS

df

MS

F

p-value

Regression

160,218.6163

1  

160,218.6163

110.22

1.02E-06

Residual

14,536.3004

10  

1,453.6300

Total

174,754.9167

11  

Regression output

confidence interval

variables

coefficients

std. error

   t (df=10)

p-value

95% lower

95% upper

Intercept

-159.4742

54.6407

-2.919

.0153

-281.2213

-37.7270

Temp

30.0879

2.8659

10.499

1.02E-06

23.7022

36.4735

Predicted values for: sales

95% Confidence Interval

95% Prediction Interval

Temp

Predicted

lower

upper

lower

upper

Leverage

20

442.2831

416.341

468.225

353.459

531.107

0.093