I NEED ANSWER OF A, B, C, D
You are probably familiar with (and may have used)
back belts, which are widely used by workers to protect their lower
backs from injuries caused by lifting. A study was conducted to
determine the usefulness of this protective gear. Here is a partial
description of the study, published in the Journal of the
American Medical Association and reported by the
Associated Press (December 5, 2000):
New research suggests that back belts, which are
widely used in industry to prevent lifting injuries, do not work.
The findings by the National Institute for Occupational Safety and
Health stem from a study of 160 Wal-Mart stores in 30 states.
Researchers [based their findings on] workers’ compensation data
from 1996 to 1998.
Although you do not know the
study’s particulars, think about how you would go about
investigating the effect of back belt usage on back injuries.
Assume that you have data on each of the 160 retail stores in your
study. For each store, you know whether back belt usage was low,
moderate, or high. You classify 50 stores as having low belt usage
by employees, 50 stores as having moderate usage, and 60 stores as
having high usage. You also know the number of back-injury workers’
compensation claims from each store. This information permits you
to calculate the mean number of claims for low-usage,
moderate-usage, and high-usage stores.
A. The following hypothesis suggests
that back belt usage helps prevent injury: In a comparison of
stores, stores with low back belt usage by employees will have more
worker injuries than will stores with high back belt usage. What is
the independent variable? What is the dependent variable? Does this
hypothesis suggest a positive or negative relationship between the
independent and dependent variables? Explain.
B. Fabricate a mean comparison table
showing a linear pattern that is consistent with the hypothesis.
Sketch a line chart from the data you have fabricated. (Because you
do not have sufficient information to fabricate a plausible mean
for all the cases, you do not need to include a “Total” row in your
mean comparison table.)
C. Use your imagination. Suppose the
data showed little difference in the worker injury claims for
low-usage and moderate-usage stores, but a large effect in the
hypothesized direction for high-usage stores. What would this
relationship look like? Sketch a line chart for this
relationship.
There us no data, you have to hypothesis
it.
In: Math
11) You are testing the claim that the proportion of men who own
cats is significantly different than the proportion of women who
own cats.
You sample 180 men, and 30% own cats.
You sample 100 women, and 70% own cats.
Find the test statistic, rounded to two decimal places.
12) You are testing the claim that the mean GPA of night
students is different than the mean GPA of day students.
You sample 60 night students, and the sample mean GPA is 2.01 with
a standard deviation of 0.53
You sample 30 day students, and the sample mean GPA is 1.75 with a
standard deviation of 0.74
Calculate the test statistic, rounded to 2 decimal places
20) Give a 98% confidence interval, for μ1-μ2 given the following information.
n1=35, ¯x1=2.69, s1=0.47
n2=25, ¯x¯2=2.42, s2=0.99
___ < μ1-μ2 < ___ Use Technology Rounded to 2 decimal places.
In: Math
An environmentalist wants to find out the fraction of oil tankers that have spills each month.
Step 2 of 2:
Suppose a sample of 356 tankers is drawn. Of these ships, 246 did not have spills. Using the data, construct the 90% confidence interval for the population proportion of oil tankers that have spills each month. Round your answers to three decimal places.
In: Math
The goodness of fit of a statistical model describes how well it fits a set of observations. Measures of goodness of fit typically summarize the discrepancy between observed values and the values expected under the model in question.
Such measures may be used in statistical hypothesis testing, for example, to test for normality of residuals, to test whether two samples are drawn from identical distributions, or rather outcome frequencies follow a specified distribution (Pearson's chi-squared test).
In the analysis of variance one of the components in
to which the variance is partitioned may be a lack of fit sum of
squares. In other words, it tells you if your sample data
represents the data you would expect to find in the actual
population.
Please in a minimum of 200 words:
What good is this information to us? Why would we need to know something like this?
In: Math
A company that makes car accessories. The company control its production process by periodically taking a sample of 99 units from the production line. Each product is inspected for defective features. Control limits are developed using three standard deviations from the mean as the limit. During the last 12 samples taken, the proportion of defective items per sample was recorded as follows:
|
0.01 |
0.03 |
0.0 |
0.04 |
0.01 |
0.01 |
|
0.00 |
0.01 |
0.02 |
0.02 |
0.03 |
0.03 |
a. Determine the mean proportion defective, the UCL, and the LCL? (Marks 1) (word count maximum:150)
b. Draw a control chart and plot each of the sample measurements on it? (Marks 1) (word count maximum:100)
c. Does it appear that the process for making tees is in statistical control? (Marks 0.5) (word count maximum:100)
In: Math
In a study of high-achieving high school graduates, the authors
of a report surveyed 834 high school graduates who were considered
"academic superstars" and 436 graduates who were considered "solid
performers." One question on the survey asked the distance from
their home to the college they attended.
Assuming it is reasonable to regard these two samples as random
samples of academic superstars and solid performers nationwide, use
the accompanying data to determine if it is reasonable to conclude
that the distribution of responses over the distance from home
categories is not the same for academic superstars and solid
performers. Use
α = 0.05.
| Distance of College from Home (in miles) | |||||
|---|---|---|---|---|---|
| Student Group | Less than 40 |
40 to 99 |
100 to 199 |
200 to 399 |
400 or More |
| Academic Superstars | 158 | 157 | 143 | 150 | 226 |
| Solid Performers | 105 | 94 | 83 | 65 | 89 |
State the null and alternative hypotheses.
H0: Student group and distance of college
from home are independent.
Ha: Student group and distance of
college from home are not independent. H0:
Student group and distance of college from home are not
independent.
Ha: Student group and distance of
college from home are independent.
H0: The proportions falling into the distance
categories are not all the same for the two student groups.
Ha: The proportions falling into the
distance categories are the same for the two student groups.
H0: The proportions falling into the distance
categories are the same for the two student groups.
Ha: The proportions falling into the
distance categories are not all the same for the two student
groups.
Calculate the test statistic. (Round your answer to two decimal
places.)
χ2 =
What is the P-value for the test? (Round your answer to
four decimal places.)
P-value =
What can you conclude?
Do not reject H0. There is not enough evidence to conclude that the proportions falling into the distance categories are not all the same for the two student groups. Reject H0. There is convincing evidence to conclude that the proportions falling into the distance categories are not all the same for the two student groups. Reject H0. There is convincing evidence to conclude that there is an association between student group and distance of college from home. Do not reject H0. There is not enough evidence to conclude that there is an association between student group and distance of college from home.
In: Math
Following are age and price data for 8 randomly selected ambulances between 1 and 6 years old. Here, x denotes age, in years, and y denotes price, in hundreds of dollars. Use the information to do parts (a) through (d).
x 6 1 6 2 6 2 4 5
y 280 420 275 360 265 350 325 305
Summation from nothing to nothing x equals 32 ∑x=32, Summation from nothing to nothing y equals 2580 ∑y=2580, Summation from nothing to nothing xy equals 9585 ∑xy=9585, Summation from nothing to nothing x squared equals 158 ∑x2=158
a. Compute SST, SSR, and SSE, using the formulas,
SST = ________ (Round to two decimal places as needed.)
b. compute the coefficient of determination, r2.
c. Determine the percentage of variation in the observed values of the response variable explained by the regression, and intrepret you answer.
d.State how useful the regression equation appears to be making predictions
In: Math
The average commute time in Oregon is 24 minutes, with a standard deviation of 4 minutes. For the 3 drivers in my household, what is the probability that our average commute time is over 27 minutes per day?
In: Math
Are sexually active teenagers any better informed about AIDS and other potential health problems related to sex than teenagers who are sexually inactive? A 15-item test of general knowledge about sex and health was administered to random samples of teens who are sexually inactive, teens who are sexually active but with only a single partner, and teens who are sexually active with more than one partner. Is there any significant difference in the test scores?
Inactive:10,12,8,10,8,5
active one partner: 11,11,6,5,15,10
active more than one partner 12,12,10,4,3,15
can you please explain all the steps and not do it in excel.
In: Math
After game 1 of the World Series (of baseball, a best-of-seven series), the announcers announced that over the previous 20 years, it had happened 12 times that the team that won the first game went on to win the series. They seemed to be suggesting that winning a series 60% of the time was surprisingly high. Is it? In other words, assuming that the two teams are equally likely to win a game and that the games are independent events, what is the probability that the team that won the first game wins the series?
In: Math
Why is the EWMA chart robust to non-normality whereas the Individuals-Moving Range chart is not?
In: Math
Consider the following dependent random samples
Observations
1
2
3
4
5 6
x-values
8.8 7.9 8.0 8.4
8.2 8.0
y-values 7.7 7.3 8.0
8.9 7.5 7.8
a) Determine the difference between each set of points, xi - yi
b) Do hypothesis testing to see if µd < 0 at the α = .025.
In: Math
An advertising firm wanting to target people with strong desires for success conducted a study to see if such people differed in the types of television shows they watched. Randomly selected participants recorded the shows they watched for a week, then their desire for success was assessed, and finally, they were divided into two groups. Low Success seekers watched 8 comedies, 15 romances, 6 documentaries, 13 dramas, and 3 news shows. High Success seekers watched 3 comedies, 3 romances, 9 documentaries, 7 dramas, and 8 news shows.
Question- conduct a Chi-Squared for independence test using the SPSS program and paste the output information and state the results.
In: Math
1. A researcher wants to know if being monolingual, bilingual, or multilingual is related to which country a person is from. To assess this, a large group of people were surveyed. The results of that survey are reported below. Are the traits related?
| obs freq | monolingual | bilingual | multilingual |
| USA | 127 | 12 | 10 |
| CANADA | 84 | 25 | 12 |
| MEXICO | 134 | 9 | 8 |
| ENGLAND | 133 | 23 | 19 |
| SPAIN | 56 | 49 | 17 |
| FRANCE | 108 | 25 | 15 |
| GERMANY | 47 | 80 | 14 |
In: Math
The accompanying data on degree of spirituality for a sample of natural scientists and a sample of social scientists working at research universities appeared in a paper. Assume that it is reasonable to regard these two samples as representative of natural and social scientists at research universities. Is there evidence that the spirituality category proportions are not the same for natural and social scientists? Test the relevant hypotheses using a significance level of 0.01.
| Degree of Spirituality | ||||
|---|---|---|---|---|
| Very | Moderate | Slightly | Not at All | |
| Natural Scientists | 54 | 158 | 193 | 211 |
| Social Scientists | 57 | 227 | 240 | 242 |
State the null and alternative hypotheses.
H0: The spirituality category proportions
are not all the same for natural scientists and social
scientists.
Ha: The spirituality category
proportions are the same for natural scientists and social
scientists. H0: The spirituality category
proportions are the same for natural scientists and social
scientists.
Ha: The spirituality category
proportions are not all the same for natural scientists and social
scientists. H0: The
spirituality category for natural scientists and social scientists
are independent.
Ha: The spirituality category for
natural scientists and social scientists are not independent.
H0: The spirituality category for natural
scientists and social scientists are not independent.
Ha: The spirituality category for
natural scientists and social scientists are independent.
Calculate the test statistic. (Round your answer to two decimal
places.)
χ2 =
What is the P-value for the test? (Round your answer to
four decimal places.)
P-value =
What can you conclude?
Do not reject H0. There is not enough evidence to conclude that the spirituality category proportions are not all the same for natural scientists and social scientists. Reject H0. There is convincing evidence to conclude that there is an association between natural scientists and social scientists. Do not reject H0. There is not enough evidence to conclude that there is an association between natural scientists and social scientists. Reject H0. There is convincing evidence to conclude that the spirituality category proportions are not all the same for natural scientists and social scientists.
You may need to use the appropriate table in Appendix A to answer
this question.
In: Math