In: Statistics and Probability
A suburban hotel derives its revenue from its hotel and restaurant operations. The owners are interested in the relationship between the number of rooms occupied on a nightly basis and the revenue per day in the restaurant. Below is a sample of 25 days (Monday through Thursday) from last year showing the restaurant income and number of rooms occupied.
| Day | Revenue | Occupied | Day | Revenue | Occupied | ||||||||
| 1 | $ | 1,452 | 60 | 14 | $ | 1,425 | 31 | ||||||
| 2 | 1,361 | 20 | 15 | 1,445 | 51 | ||||||||
| 3 | 1,426 | 21 | 16 | 1,439 | 62 | ||||||||
| 4 | 1,470 | 80 | 17 | 1,348 | 45 | ||||||||
| 5 | 1,456 | 70 | 18 | 1,450 | 41 | ||||||||
| 6 | 1,430 | 29 | 19 | 1,431 | 62 | ||||||||
| 7 | 1,354 | 30 | 20 | 1,446 | 47 | ||||||||
| 8 | 1,442 | 21 | 21 | 1,485 | 43 | ||||||||
| 9 | 1,394 | 15 | 22 | 1,405 | 38 | ||||||||
| 10 | 1,459 | 36 | 23 | 1,461 | 36 | ||||||||
| 11 | 1,399 | 41 | 24 | 1,490 | 30 | ||||||||
| 12 | 1,458 | 35 | 25 | 1,426 | 65 | ||||||||
| 13 | 1,537 | 51 | |||||||||||
the scatterplot of the given data is

using excel>data>data analysis>Regression
we have
| Regression Analysis | ||||||
| Regression Statistics | ||||||
| Multiple R | 0.333809151 | |||||
| R Square | 0.11142855 | |||||
| Adjusted R Square | 0.072795008 | |||||
| Standard Error | 41.20806786 | |||||
| Observations | 25 | |||||
| ANOVA | ||||||
| df | SS | MS | F | Significance F | ||
| Regression | 1 | 4897.748295 | 4897.748295 | 2.884243735 | 0.102940121 | |
| Residual | 23 | 39056.4117 | 1698.104857 | |||
| Total | 24 | 43954.16 | ||||
| Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | |
| Intercept | 1399.801394 | 22.61097777 | 61.90804345 | 4.33867E-27 | 1353.027023 | 1446.575765 | 
| Occupied | 0.843363346 | 0.496590884 | 1.698306137 | 0.102940121 | -0.183913166 | 1.870639857 | 
the p value of F stat is 0.1029 which is greater than 0.05 so we conclude that there exist no relationship between the number of rooms occupied on a nightly basis and the revenue per day in the restaurant.
Using t test
the value of r = 0.334
n = 25
the null and alternative hypothesis is
H0: ρ ≤ 0;
H1: ρ > 0 (one tailed)
=
= 1.70
1. the decision rule for 0.01 significance level: is reject Ho if t > 2.50
since value of test stat t is < 2.50 so reejct Ho
2.] 11.1 percent of the variation in revenue in the restaurant is accounted for by the number of rooms occupied