Random sample of coin weights
Quarter Nickel Penny
7.9 9.5 6.7
7.2 7.0 7.1
7.8 8.7 6.5
8.1 7.6 7.1
7.9 N/A 5.5
Test at a 1% level of significance whether the population mean
weights of any two watchband
types are different? State the required assumptions for the test.
Hint: Use sum of x^2=794.02
Fit a multiple linear regression model of the form y=β0 + β1 x1
+ β2 x2 + β3 x3 + ε. Here, ε is the random error term that is
assumed to be normally distributed with 0 mean and constant
variance. State the estimated regression function. How are the
estimates of the three regression coefficients interpreted here?
Provide your output, and interpretations in a worksheet titled
“Regression Output.”
Obtain the residuals and prepare a box-plot of the residuals.
What information...
Assignment on Multiple Linear Regression
The Excel file BankData shows the values of the following
variables for randomly selected 93 employees of a bank. This real
data set was used in a court lawsuit against discrimination.
Let
= monthly salary in dollars (SALARY),
= years of schooling at the time of hire (EDUCAT),
= number of months of previous work experience (EXPER),
= number of months that the individual was hired by the bank
(MONTHS),
= dummy variable...
We consider the multiple linear regression with LIFE (y) as the
response variable, and MALE, BIRTH, DIVO , BEDS, EDUC, and INCO, as
predictors.
QUESTION: Plot the standardized residuals against the fitted
values. Are there any notable points. In particular look for points
with large residuals or that may be influential.
# please screenshot the Rcode for the plot.
# data information are as follows:
"STATE" "MALE" "BIRTH" "DIVO" "BEDS" "EDUC" "INCO" "LIFE"
AK 119.1 24.8 5.6 603.3 14.1 4638...
What is the difference between simple linear regression and
multiple linear regression?
What is the difference between multiple linear regression and
logistic regression?
Why should you use adjusted R-squared to choose between models
instead of R- squared?
Use SPSS to:
Height (Xi)
Diameter (Yi)
70
8.3
72
10.5
75
11.0
76
11.4
85
12.9
78
14.0
77
16.3
80
18.0
Create a scatterplot of the data above. Without conducting a
statistical test, does it look like there is a linear...
Questions 16-23
A multiple linear regression was used to study how family spending
( y) is influenced by income ( x 1),
family size ( x 2), and additions to savings (
x3). The variables y, x
1, and x 3 are measured in thousands
of dollars per year. The following results were obtained.
ANOVA
DF
SS
Regression
42.450
Residual
11
2.141
Total
Coefficients
Standard Error
Intercept
0.012
x 1
0.742
0.071
x 2
0.201
0.186
x 3
-0.540...
When we estimate a linear multiple regression model (including a
linear simple regression model), it appears that the calculation of
the coefficient of determination, R2, for this model can be
accomplished by using the squared sample correlation coefficient
between the original values and the predicted values of the
dependent variable of this model.
Is this statement true? If yes, why? If not, why not? Please use
either matrix algebra or algebra to support your reasoning.
Regression
Make a distinction between simple linear and multiple linear
regression. Can you think of examples in your business world where
these techniques are or should be applied? Share the details, where
possible.