Recall that "very satisfied" customers give the XYZ-Box video
game system a rating that is at least 42. Suppose that the
manufacturer of the XYZ-Box wishes to use the random sample of 64
satisfaction ratings to provide evidence supporting the claim that
the mean composite satisfaction rating for the XYZ-Box exceeds
42.
(a) Letting µ represent the mean
composite satisfaction rating for the XYZ-Box, set up the null
hypothesis H0 and the alternative hypothesis
Ha needed if we wish to attempt to provide
evidence supporting the claim that µ exceeds 42.
H0: µ (Click to select)=≠≤><≥
42 versus Ha: µ (Click to
select)≥=>≤<≠ 42.
(b) The random sample of 64 satisfaction ratings yields a sample mean of x¯=42.970x¯=42.970. Assuming that σ equals 2.67, use critical values to test H0 versus Ha at each of α = .10, .05, .01, and .001. (Round your answer z.05 to 3 decimal places and other z-scores to 2 decimal places.)
z =
Rejection points | |
z.10 | |
z.05 | |
z.01 | |
z.001 | |
Reject H0 with α = (Click to
select).001.10.10, .05, .01.01, .001 , but not with α
=(Click to select).10.10, .05, .01.01, .001.001
(c) Using the information in part (b),
calculate the p-value and use it to test
H0 versus Ha at each of
α = .10, .05, .01, and .001. (Round your answers
to 4 decimal places.)
p-value = | |
Since p-value = is less than (Click to select).10, .05, .01.01, .001.001.10 ; reject H0 at those levels of α but not with α = (Click to select).10.001.01, .001.10, .05, .01. |
(d) How much evidence is there that the mean composite satisfaction rating exceeds 42?
There is (Click to select)very strongextremely strongnoweakstrong
evidence.
In: Math
Provide formula for effect sizes and step-by-step solution by hand or software.
A researcher is studying the effects of inserting questions into
instructional material for learning. There is doubt whether these
questions would be more effective before or after the corresponding
passage. In addition, the researcher wants to know the impact of
factual and thought provoking questions. Students are randomly
assigned to one of each of the four combination: position of
question (before vs. after the passage) and type of question
(factual vs. thought provoking). After 15 hours of studying under
these conditions, the students are given a test on the content of
the instructional materials. The test scores are below. What can be
concluded with α = 0.01?
Position
Type | before | after |
---|---|---|
factual | 21 31 32 25 28 19 |
29 24 33 26 25 30 |
thought | 27 20 15 21 26 24 |
36 39 41 29 31 35 |
a) What is the appropriate test statistic?
---Select--- na one-way ANOVA within-subjects ANOVA two-way
ANOVA
b) Compute the appropriate test statistic(s) to
make a decision about H0.
Type: critical value = ; test statistic
=
Decision: ---Select--- Reject H0 Fail to reject H0
Position: critical value = ; test
statistic =
Decision: ---Select--- Reject H0 Fail to reject H0
Interaction: critical value = ; test
statistic =
Decision: ---Select--- Reject H0 Fail to reject H0
c) Compute the corresponding effect size(s) and
indicate magnitude(s).
Type: η2
= ; ---Select--- na trivial effect small
effect medium effect large effect
Position: η2
= ; ---Select--- na trivial effect small
effect medium effect large effect
Interaction: η2
= ; ---Select--- na trivial effect small
effect medium effect large effect
d) Make an interpretation based on the
results.
There is a question type difference in the test scores.There is no question type difference in the test scores.
There is a question position difference in the test scores.There is no question position difference in the test scores.
There is a question type by position interaction in the test scores.There is no question type by position interaction in the test scores.
In: Math
Given the data listed in the table, calculate the lower and upper bound for the 95% confidence interval for the mean at X = 7. The regression equation is given by y^ = b0 + b1x.
Regression Statistics | ||
---|---|---|
Statistic | Value | |
b0 | 4.3 | |
b1 | 0.50 | |
x | 5.36 | |
se | 3.116 | |
SSX | 25.48 | |
SST | 58.25 | |
n | 40 |
Give your answers to 2 decimal places. You may find this Student's t distribution table useful.
a) Lower bound =
b)Upper bound =
In: Math
One generator is placed in standby redundancy to the main generator. The faliure rate of each generator is estimated to be λ = 0.05/hr. Compute the reliability of the system for 10 hrs and its MTBF assuming that the sensing and switching device is 100% reliable. If the reliability of this device is only 80%, how are the results modified?
In: Math
PLEASE DO BY HAND AND NOT EXCEL
1.A car dealer believes that average daily sales for four different dealerships in four separate states are equal. A random sample of days results in the following data on daily sales:
Ohio New York West Virginia Pennsylvania
3 10 3 20
2 0 4 11
6 7 5 8
4 8 2
4 0 14
7
2
Use ANOVA to test this claim at the 0.05 level.
In: Math
What does it mean to say that a particular result is statistically significant at the .05 level or at the .01 level? Is a result that is statistically significant at the .05 level automatically also significant at the .01 level? What about the reverse? Please explain your reasoning.
In: Math
1. Do consumers spend more on a trip to Walmart or
Target? Suppose researchers interested in this question collected a
systematic sample from 85 Walmart customers and 80 Target customers
by asking customers for their purchase amount as they left the
stores. The data collected are summarized in the table below.
Walmart
Target
sample size
85
80
sample mean
$45
$53
sample std dev
$20
$18
a. Check the conditions to create a confidence
interval for the difference in spending at the two stores.
b. Create a 95% confidence interval for the difference
in spending at the two stores. (Note: We don’t have the full data,
so you can use the formulas on page 342 or a program that doesn’t
require it.)
c. Interpret your confidence interval with a
sentence.
d. Your CI from part b does not contain zero. Does that
mean the difference in spending at the two stores is statistically
significant? Why or why not?
In: Math
We have:
P(A) = 0.75
P(B|A) = 0.9
P(B|A′) = 0.8
P(C|A ∩ B) = 0.8
P(C|A ∩ B′) = 0.6
P(C|A′ ∩ B) = 0.7
P(C|A′ ∩ B′) = 0.3
Compute:
a) ?(?′| ?′)
b) P (?′ ∪ ?′)
c) ?(? ∩ ? ∩ ?)
d) P(C)
e) ?(? ∩ ? ∩ ?)’
f) P(B)
g) P(AUBUC)
In: Math
The life in hours of a thermocouple used in a furnace is known to be ap-
proximately normally distributed, with standard deviation
σ
= 20 hours. A
random sample of 15 thermocouples resulted in he following data: 553, 552,
567, 579, 550, 541, 537, 553, 552, 546, 538, 553, 581, 539, 529.
Use the 5 steps in the testing procedure to solve following question:
a) Is there evidence to support the claim that mean life exceeds 540 hours?
Use a fixed-level test with
α
= 0
.
05.
b) What is the P-value for this test?
c) Construct a 95% one-sided lower CI on the mean life.
d) Use the CI found above to test the hypothesis.
e) What is the β-value for this test if the true mean life is 560 hours?
In: Math
PART 1.
A study reports the following final notation: F (2, 12) = 5.00, p
> .05
a. How many samples were involved in this study?
b. How many total participants were involved in this study?
c. If MSwithin is 3, what is MSbetween?
PART 2.
Test the claim that the mean GPA for student athletes is higher
than 3.1 at the .01 significance level.
Based on a sample of 50 people, the sample mean GPA was 3.15 with a
standard deviation of 0.08
The test statistic is: (to 3 decimals)
The p-value is: (to 3 decimals)
Based on this we:
In: Math
Total plasma volume is important in determining the required plasma component in blood replacement therapy for a person undergoing surgery. Plasma volume is influenced by the overall health and physical activity of an individual. Suppose that a random sample of 40 male firefighters are tested and that they have a plasma volume sample mean of x = 37.5 ml/kg (milliliters plasma per kilogram body weight). Assume that σ = 7.80 ml/kg for the distribution of blood plasma.
(a)
Find a 99% confidence interval for the population mean blood plasma volume in male firefighters. What is the margin of error? (Round your answers to two decimal places.)
lower limitupper limitmargin of error
(b)
What conditions are necessary for your calculations? (Select all that apply.)
the distribution of weights is uniformσ is knownn is largethe distribution of weights is normalσ is unknown
(c)
Interpret your results in the context of this problem.
1% of the intervals created using this method will contain the true average blood plasma volume in male firefighters.The probability that this interval contains the true average blood plasma volume in male firefighters is 0.01. The probability that this interval contains the true average blood plasma volume in male firefighters is 0.99.99% of the intervals created using this method will contain the true average blood plasma volume in male firefighters.
(d)
Find the sample size necessary for a 99% confidence level with maximal margin of error E = 2.00 for the mean plasma volume in male firefighters. (Round up to the nearest whole number.)
male firefighters
In: Math
Steve is the director of operations for a diamond company. The company is considering whether to launch a new product line, which will require building a new facility. The research required to produce the new product has not been proven to work in a full-scale operation. If Steve decides to build the new facility and the process is successful, the company will earn a profit of 720,000. If the process is unsuccessful, his company will realize a loss of 900,000. Steve estimates that the probability of the full-scale process succeeding is 62%. Steve has the option of constructing a pilot plant for 59,000 to test the new process before deciding to build the full-scale facility. He estimates there is a 54% probability that the pilot plant will prove successful. If the pilot plant succeeds he thinks the chance of the full scale facility succeeding is 87%. if the pilot plant fails, he thinks the chance of the full scale facility succeeding is only 35%. Complete parts a, b, and c below.
A.) Construct a decision tree with all of the known information labeled
B.) Advise what to do ( should he build the pilot plant first?)
C.) what is the most they should pay to construct the pilot plant?
In: Math
A queuing system with a Poisson arrival rate and exponential service time has a single queue, two servers, an average arrival rate of 60 customers per hour, and an average service time of 1.5 minutes per customer.
The manager is thinking of implementing additional queues to avoid an overloaded system. What is the minimum number of additional queues required? Explain.
How many additional servers are required to ensure the utilization is less than or equal to 50%? Explain.
If the manager loses a server, what service time would be necessary to ensure that the queue length is not at risk of approaching infinity? Explain.
In: Math
In: Math
PLEASE DO BY HAND AND NOT EXCEL
X Y
2 70
0 70
4 130
a. Test to see whether X and Y are significantly related using a t-test on the slope of X. Test this at the 0.05 level.
b. Test to see whether X and Y are significantly related using an F-test on the slope of X. Test this at the 0.05 level.
In: Math