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
A screening program for neuroblastoma (a type of cancer) was undertaken in Germany among children born between November 1, 1993, and June 30, 2000, who were between 9 and 18 months of age between May 1995 and April 2000. A total of 1,475,773 children participated in the screening program. Of whom 204 were diagnosed between 12 and 60 months of age. The researchers expected the incidence rate of neuroblastoma to be 7.3 per 100,000 children during this period in the absence of screening. We wish to test if the number of cases detected by the screening program is significantly greater than expected.
a) Write hypotheses to test this claim. Explain why you should use a one sided alternative.
b) You may assume any necessary conditions have been met. Perform your test.
c) Do you think that the number of cases detected by the screening program is significantly greater than expected? Explain.
d) Give a 95% confidence interval for the incidence rate of neuroblastoma in the screened population.
e) Express your confidence interval from part d) as (p1, p2), where p1 and p2 are in the units of number of cases per 100,000 children.
specifically need help with question e
In: Math
How would you ensure that your sample is not biased?
What are the effects of a large sample size to the distribution of the bell curve?
In: Math
Is smoking during pregnancy associated with premature births? To investigate this question, researchers selected a random sample of 148 pregnant women who were smokers. The average pregnancy length for this sample of smokers was 262 days. From a large body of research, it is known that length of human pregnancy has a standard deviation of 16 days. The researchers assume that smoking does not affect the variability in pregnancy length.
Find the 95% confidence interval to estimate the length of pregnancy for women who smoke.
(Note: The critical z-value to use, zc, is: 1.960)
( , )
Your answer should be rounded to 3 decimal places.
In: Math
Imagine that you are a physician and you have just received the results back for a patient of yours who has just tested positive for the “heartbreak of psoriasis”. The test used will correctly label a person who is suffering from the “heartbreak of psoriasis” as a sufferer 90% of the time and will correctly label a person who is not suffering from the “heartbreak of psoriasis” as not being a sufferer 60% of the time. If the base-rate of suffering from the “heartbreak of psoriasis” is 5%, explain to your patient how likely she is actually suffering from the “heartbreak of psoriasis” on the basis of this positive result.
I got 7.32% using Bayes Theorem. Is this right?
In: Math
What are companies' biggest obstacles to attracting the best talent? Of 1,000 surveyed U.S. and Canadian talent acquisition professionals, 510 reported that competition for talent is the biggest obstacle at their company. At the 0.01 level of significance, is there evidence that the proportion of all talent acquisition professionals who report competition is the biggest obstacle to attracting the best talent at their company is different from 47%?
In: Math