An experiment is performed to test the difference in effectiveness of two methods of cultivating wheat. A total of 12 patches of ground are treated with shallow plowing and 14 with deep plowing. The average yield per ground area of the shallow plowing group is 45.2 bushels, and the average yield for the deep plowing group is 48.6 bushels. Suppose it is known that shallow plowing results in a ground yield having a standard deviation of 0.8 bushels, while deep plowing results in a standard deviation of 1.0 bushels. A the 0.05 level of significance, a researcher wants to test the given data if it is consistent with the hypothesis that the mean yield is the same for both methods. What is the variable of interest of the study? Methods of cultivating wheat a. b. Types of wheat

An experiment is performed to test the difference in effectiveness of two methods of cultivating wheat. A total of 12 patches of ground are treated with shallow plowing and 14 with deep plowing. The average yield per ground area of the shallow plowing group is 45.2 bushels, and the average yield for the deep plowing group is 48.6 bushels. Suppose it is known that shallow plowing results in a ground yield having a standard deviation of 0.8 bushels, while deep plowing results in a standard deviation of 1.0 bushels. A the 0.05 level of significance, a researcher wants to test the given data if it is consistent with the hypothesis that the mean yield is the same for both methods. What is the variable of interest of the study? Methods of cultivating wheat a. b. Types of wheat

Name: An experiment is performed to test the difference in effectiveness of
Uploaded: 2024-03-20T07:07:12.000Z
Channel: Bartleby
Description: An experiment is performed to test the difference in effectiveness of two methods of cultivating wheat.A total of 12 patches of ground are treated with shallow plowing and 14 with deep plowing. The averageyield per ground area of the shallow plowing

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

Consider a dataset containing the heights of 38 females who said they prefer to sit inthe front of the classroom yields a sample average of 62 inches and a samplestandard deviation of 2.5 inches. Suppose that the average height for the generalpopulation of college females is 65 inches. An analyst wants to test the claim thatthe true average height of females who prefer to sit in the front of the classroom islower than it is for the general population. Comparing your conclusion using the 95% Cl for the true average height to the TRUTH that the mean height of females who prefer to sit in front of the classroom as 60 inches, we have that: a) a Type II error has occured b) the decision/conclusion is not an error c) no assessment can be made because normality is not given d) a Type I error has occured
The average gasoline price of one of the major oil companies has been $2.20 per gallon.because of the cost reduction measures,it is believed that there has been a significant reduction in the average price.in order to test this belief,we randomly selected a sample of 36 of the company's gas stations and determined that the average price for the stations in the sample was $2.14.assume that the standard deviation of the population is $0.12. a)state the null and alternative hypothesis in words and in symbols. b)compute the test statistics C)what is the p_value associate with the above sample results? d)at 95% confidence,test the company claim.
Stats #7
A comparison between species: Biologists comparing the gestation period of two newly discovered species of frog collected data from 14 frogs of species A and 28 frogs of species B. Species A exhibited an average gestation period of 10 days with a standard deviation of 3.1 days while species B had a gestation period of 16 days and a standard deviation of 5 days. The researchers want to know whether the average lengths of the gestational periods differ between the two species. Conduct a hypothesis test at a significance level of a = 0.05.
The average weight of new-born kittens is 3.5 ounces. A breeder suspects one of her cats, Stella, produces extra small kittens. The breeder’s suspicions arise from the weights of Stella’s most recent litter of kittens: {3.1, 3.3, 3.0, 3.7, 2.9, 2.9}. Note that the sample mean is15 oz. Assume that the standard deviation of the weight of all Stella’s new-born kittens is 0.3 oz. Test at the 5% significance level whether the average weight of Stella’s new-born kittens is below 3.5 oz. Complete all 6 steps of your hypothesis test, including a discussion of the assumptions. Obtain and interpret a 90% two-sided confidence interval for the mean weight of all Stella’s new-born kittens Does the interval in part (2) give evidence that the average weight of Stella’s new-born kittens differs from 3.5 oz? Explain.
Under the old method of postoperative treatment, the mean length of patients' hospital stay was 7.2 days. A new method of postoperative treatment was evaluated for patients undergoing a certain surgical procedure. 165 patients are recruited, and they all received the new method. The sample mean for the new method was 6.9 days, and the standard deviation was 0.24 days. a. The researcher who propose the new method says that since the mean days using the new method is less than 7.2, the new method is better. Explain why this reasoning is incorrect. b. The new method would be used if it can shorten the length of hospital stay. State the appropriate null and alternate hypothesis determine whether the new method should be used. c. Compute the P-value. Would you recommend using the new method? Explain.
A weight loss clinic with 250 clients reported an annual mean loss of 24.5 pounds with a standard deviation of 6.3. Construct a 95% CI for the true population weight loss.
Suppose that an independent research company was tasked with testing the validity of complaints against a pesticide manufacturing firm for under-filling their 20 lb bags of pesticide. Past experience has shown that the amount of pesticide dispensed by the machines that fill the bags follows a normal distribution with a mean of 20 lb and a standard deviation of 0.6 lb. To verify the validity of the complaints, a researcher randomly selected 16 of the firm's 20 lb pesticide bags and recorded the following weights. 19.69, 19.5, 18.85, 18.56, 20.23, 20.3, 20.14, 19.11, 19.65, 18.87, 19.22, 19.24, 18.82, 20.23, 20.46, 18.66 The mean weight of the 16 bags collected was 19.471 lb. Calculate the value of the one-sample z‑ statistic. Give your answer precise to three decimal places.
An ecologist is examining whether the number of fish caught in a large river basin has changed since a fire burned some of the surrounding forested area and vegetation along the river. Data in the form of fishing reports was available for a five-year period before the fire. From a random sample of 195 fishing reports before the fire, the mean catch was 6.3 fish with a standard deviation of 1.6. In a random sample of 143 reports three years after the fire, the mean catch was 7.1 fish with a standard deviation of 2.1. Which of the following represents the standard error of the difference in the mean number of fish caught before and after the fire?
Suppose that an independent research company was tasked with testing the validity of complaints against a pesticide manufacturing firm for under-filling their 20 lb bags of pesticide. Past experience has shown that the amount of pesticide dispensed by the machines that fill the bags follows a normal distribution with a mean of 20 lb and a standard deviation of 0.6 lb. To verify the validity of the complaints, a researcher randomly selected 16 of the firm's 20 lb pesticide bags and recorded the following weights: 20.16, 20.41, 19.96, 20.32, 18.69, 18.68, 18.6, 19.11, 18.9, 18.75, 19.29, 19.61, 19.31, 20.44, 19.52, 19.98. The mean weight of the 16 bags collected was 19.483 lb. Calculate the value of the one-sample ?z‑ statistic. Give your answer precise to three decimal places.
The amount of time it takes students to travel to school can vary greatly depending on how far a student lives from the school and what mode of transportation they take to school. A student claims that the average travel time to school for his large district is 20 minutes. To further investigate this claim, he selects a random sample of 50 students from the school and finds that their mean travel time is 22.4 minutes with a standard deviation of 5.9 minutes. He would like to conduct a significance test to determine if there is convincing evidence that the true mean travel time for all students who attend this school is greater than 20 minutes. What are the appropriate hypotheses? A) H0: μ = 20 versus Ha: μ < 20, where μ = the true mean travel time for all students who attend this school B) H0: μ = 20 versus Ha: μ > 20, where μ = the true mean travel time for all students who attend this school C) H0: μ = 20 versus Ha: μ < 20, where μ = the mean travel time for the 50…
Research has shown that, for baseball players, good hip range of motion results in improved performance and decreased body stress. A research article reported on a study of independent samples of 40 professional pitchers and 40 professional position players. For the pitchers, the sample mean hip range of motion was 75.8 degrees and the sample standard deviation was 5.6 degrees, whereas the sample mean and sample standard deviation for position players were 79.9 degrees and 7.2 degrees, respectively. Assuming that the two samples are representative of professional baseball pitchers and position players, test hypotheses appropriate for determining if there is convincing evidence that the mean range of motion for pitchers is less than the mean for position players. (Use ? = 0.05. Use ?1 for pitchers and ?2 for position players.)