Introduction to Linear Regression Analysis. Douglas C. Montgomery

      Example 2.9 The Delivery Time Data

      Consider the soft drink delivery time data introduced in Chapter 1. The 25 observations on delivery time y and delivery volume x are listed in Table 2.11. The scatter diagram shown in Figure 1.1 indicates a strong linear relationship between delivery time and delivery volume. The Minitab output for the simple linear regression model is in Table 2.12.

      The sample correlation coefficient between delivery time y and delivery volume x is

       TABLE 2.11 Data Example 2.9

Observation	Delivery Time, y	Number of Cases, x
1	16.68	7
2	11.50	3
3	12.03	3
4	14.88	4
5	13.75	6
6	18.11	7
7	8.00	2
8	17.83	7
9	79.24	30
10	21.50	5
11	40.33	16
12	21.00	10
13	13.50	4
14	19.75	6
15	24.00	9
16	29.00	10
17	15.35	6
18	19.00	7
19	9.50	3
20	35.10	17
21	17.90	10
22	52.32	26
23	18.75	9
24	19.83	8
25	10.75	4

       TABLE 2.12 MlNITAB Output for Soft Drink Delivery Time Data

Regression Analysis: Time versus Cases
The regression equation is
Time = 3.32 + 2.18 Cases
Predictor	Coef	SE Coef	T	P
Constant	3.321	1.371	2.42	0.024
Cases	2.1762	0.1240	17.55	0.000
S = 4.18140	R- Sq= 93.0%	R- Sq(adj) = 92.7%
Analysis of Variance
Source	DF	SS	MS	F	P
Regression	1	5382.4	5382.4	307.85	0.000
Residual Error Скачать книгу В начало < 31 32 33 34 35 36 37 38 39 > В конец e-mail: [email protected]