BUS 229 CP 28 Problems
Multiple Regression Models
1.
A mail-order catalog business that sells personal computer supplies, software, and hardware
maintains a centralized warehouse for the distribution of products ordered. Management is currently
examining
CP 27 Problems
Inference about the Slope, Correlation Coefficient and Estimation of Mean Values and Prediction of
Individual Values
1.
In our previous problem on pet foods and shelf space, the marketing manager used shelf space for pet
food to predict wee
229 CP 25 Problems
Determining the Simple Linear Regression Equation and Using It for Prediction
1.
The marketing manager of a large supermarket chain has the business objective of using shelf
space more efficiently. Toward that goal, she would like to us
229 CP 26 Problems
Measures of Variation and Durbin Watson Test
1.
In an earlier problem, you used the summated rating to predict the cost of a restaurant meal. Perform a
residual analysis for these data (stored in Restaurants2). Evaluate whether the assu
229 CP 23 Problems and Answers
F-Test for the Ratio of Two Variances
1.
2.
3.
4.
Determine the following upper tail critical values of F in each of the following two tailed tests
=0.10, n1 = 16, n2 = 20
1.87
I think there was some information missing for
229 CP 24
Determining Appropriate Two Sample Statistic
1.
Do male and female students study the same amount per week? In a recent year, 58 sophomore
business students were surveyed at a large university that has more than 1,000 business students
each year
229 CP 21
Two Sample Tests and Comparing the Means of Two Related Samples
1.
An experimental design for a paired t test has 25 pairs of identical twins. How many degrees of freedom
are there in this t test? 24 degrees of freedom
2.
Target vs Walmart: who
229 CP 22 Problems
Comparing the Proportions of Two Independent Populations
1.
2.
Let n1 = 100, X1 = 50, n2 = 100, and X2 = 30.
A.
At the the 0.05 level significance, is there evidence of a significant difference between the two
population proportions? Ye
229 CP 20 Problems
Two Sample Tests and Comparing the Means of Two Independent Samples
1.
Assume that you have a sample of n1 = 8, with the sample mean X1 = 42, and a sample standard
deviation S1 = 4, and you have an independent sample of n2 = 15 from ano
229 CP 17 Problems
Hypothesis Testing with the t test
1.
If the sample of n = 16 selected from a normal population,
tstat if you are testing null Hypothesis H0 : =50 ? 2
X
= 56 and S = 12, what is the value of
2.
In problem 1, what are the critical values
229 CP 19 Problems
Z Test of Hypothesis for the Proportion
1.
If, in a random sample of 400 items, 88 are defective, what is the sample proportion of defective items?
0.22
2.
In problem 2, if the null hypothesis is that 20% of the items in a population ar
229 CP 18 Problems
Hypothesis Testing and One Tailed Tests
1.
2.
3.
4.
5.
6.
A.
B.
C.
D.
In a one-tailed hypothesis test where you reject H0 only in the upper tail, what is the p-value if Zstat =
+2.00?
0.0228
In problem 1, what is your statistical decisi
229 CP 16 Problems
Hypothesis Testing Methodology
1.
If you use a 0.05 level of significance in a two-tailed hypothesis test. What decision will you make if Zstat
= -0.76? Do not reject the null hypothesis
2.
If you use a 0.05 level of significance in a t
229 CP 15
Confidence Interval Estimates and Determining Sample Size
1. A manufacturing company produces electric insulators for power lines. If the insulators break while in use,
a short circuit is likely to occur. To test the strength of the insulators,
CP 10
Evaluating Normality
Include screenshots of your graphical and tabular analysis in this word document and upload at the end of
class.
1.
The file SUV.xls contains the overall miles per gallon (MPG) of 2012 small SUVs (n=18). Download this
file from
229 CP 13
Confidence Interval Estimation
X = 85, = 8, n = 64, construct a 95% confidence interval estimate for the population mean, .
83.04 .86.96
X = 125, = 24, n = 24, construct a 99% confidence interval estimate for the population mean, .
2.
112.38 137
229 CP 11
Sampling Distributions
A.
B.
C.
D.
1. Given a distribution of with =100 and =10 , if you select a sample of n = 25, what is the probability
that the sample X is
less than 95? 0.006
between 95 and 97.5? 0.10565
above 102.2? 0.13567
There is a 65%
229 CP 12 Problems
Sampling Distribution of the Proportion
1. In a random sample of 64 people, 48 are classified as successful.
a. Determine the sample proportion, p of successful people. 0.75
b. If the population proportion is 70, determine the standard
229 CP 14 Problems
Confidence Interval Estimation
If X = 75, S = 24, and n = 36, and assuming that the population is normally distributed, construct a
1.
95% confidence interval estimate for the population mean, .
66.88 83.12
2. Assuming that the populati
229 CP 9
Normal Distributions and Probabilities
1.
Given a normal distribution with =100
A.
X > 75? 0.9938
B.
X < 70? 0.0013
C.
X < 80 or X > 110? 0.8186
2.
In 2011, the per capita consumption of coffee in the United States was reported to be 4.16 kg or 9
229 CP 8
1.
Given the probability distribution for two funds X and Y in the table below:
Compute the
a.
E(X) 140 and E(Y) 160
of x of y SD(X)= 48.98979 SD(Y)= 48.98979
b.
of xy -2400
c.
d.
E(X+Y) 300
2.
You are trying to develop a strategy for investing
229 CP 6 Problems
1.
While tablets sales has slowed according to a recent report by IDC, there is still strong interest in using
them to consume entertainment.
http:/www.computerworld.com/s/article/9248653/IDC_drops_tablet_sales_forecast_sees_phablets_enc
BIA 229 CP 5
1.
What is the preferred way to order fast food? A survey conducted in 2009 but the sample sizes were not
reported. Suppose the results based on the sample of 100 males and 100 females, were as follows:
If a respondent is selected at random,
229 CP 7
1.
Below are two distributions interruptions per day in two large computer networks (A and B).
1. Compute the expected value for each distribution
Network A
Standard
Deviation
# Interruptions
P(X=x)
0
0.5
0
1
0.2
0.2
2
0.15
0.3
3
0.1
0.1
4
0.05
0
229 CP 4
1.
A manufacturing company produces electric insulators for power lines. If the insulators break while in
use, a short circuit is likely to occur. To test the strength of the insulators, destructive testing is carried
out to determine how much fo
BIA 229 CP2
1.
Who goes to the train the trainers workshop?
A firm has the following 30 junior associates and 10 senior associates. The need to select 4 junior
associates and 2 senior associates.
Junior Associates
1 Chen
5 Pearl
9 Ghosh
13 Shank
17 Robert