In: Statistics and Probability
Using Excel:
Regression Statistics | ||||
Multiple R | 0.9021 | |||
R- Square | 0.8138 | |||
Adjusted R Square | 0.7828 | |||
Standard Error | 9.4006 | |||
ANOVA | ||||
df | SS | MS | F | |
Regression | 1 | 2317.6 | 2317.6 | 26.226 |
Residual | 6 | 530.23 | 88.372 | |
Total | 7 | 2847.9 | ||
Coefficients | Standard Error | t Stat | P-value | |
Intercept | 45.897 | 5.5447 | 8.2776 | 0.0002 |
Number of Surgeries (x) | 5.1951 | 1.0144 | 5.1211 | 0.0022 |
1. r = 0.90 strong positive correlation 2. y = 5.195 x + 45.897 , 3. r2 = 0.8138 , and 4. Se = 9.4006
5. Results of the Pearson correlation indicated that there was a significant positive association between age and number and surgeries with r = 0.90 . The results of the regression indicated the predictor explained 81% of the variance (R2 =0.81, F(1,6)= 26.2, p < 0.01).
Exercise 1: Use the sample data below to answer the following question(s). The paired data consist of the cost of regionally advertising (in thousands of dollars) a certain pharmaceutical drug and the number of new prescriptions written (in thousands).
Cost | 9 | 2 | 3 | 4 | 2 | 5 | 9 | 10 |
Number | 85 | 52 | 55 | 68 | 67 | 86 | 83 | 73 |
we will solve it by using excel and the steps are
Enter the Data into excel
Click on Data tab
Click on Data Analysis
Select Regression
Select input Y Range as Range of dependent variable.
Select Input X Range as Range of independent variable
click on labels if your selecting data with labels
click on ok.
So this is the output of Regression in Excel.
SUMMARY OUTPUT | ||||||||
Regression Statistics | ||||||||
Multiple R | 0.7077 | |||||||
R Square | 0.5009 | |||||||
Adjusted R Square | 0.4177 | |||||||
Standard Error | 2.5473 | |||||||
Observations | 8.0000 | |||||||
ANOVA | ||||||||
df | SS | MS | F | Significance F | ||||
Regression | 1.0000 | 39.0678 | 39.0678 | 6.0209 | 0.0495 | |||
Residual | 6.0000 | 38.9322 | 6.4887 | |||||
Total | 7.0000 | 78.0000 | ||||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | |
Intercept | -7.2756 | 5.2839 | -1.3769 | 0.2177 | -20.2048 | 5.6536 | -20.2048 | 5.6536 |
Number | 0.1796 | 0.0732 | 2.4538 | 0.0495 | 0.0005 | 0.3587 | 0.0005 | 0.3587 |
1)the value of the linear correlation coefficient r = 0.7077
2) the equation of the regression line, letting Number of Surgeries be the independent (x) variable
Cost = -7.2756+0.1796Number of Surgeries
3)t he coefficient of determination.
R-square = 0.5009
4)
the standard error of estimate se = 2.5473