A researcher wants to asses the self-discipline levels among undergraduate and graduate students. A random sample of 300 undergraduate students was selected with average score of 184 and standard deviation of 16 ( group 1). Also , a random sample of 350 graduate students was selected with average score of 153 and standard deviation of 21 ( group 2). Is this enough evidence to conclude that undergraduate students score less, on average than the graduate students. [ assume that the population variances are equals].

A researcher wants to asses the self-discipline levels among undergraduate and graduate students. A random sample of 300 undergraduate students was selected with average score of 184 and standard deviation of 16 ( group 1). Also , a random sample of 350 graduate students was selected with average score of 153 and standard deviation of 21 ( group 2). Is this enough evidence to conclude that undergraduate students score less, on average than the graduate students. [ assume that the population variances are equals].

Name: A researcher wants to asses the self-disciplinelevels among undergrad
Uploaded: 2024-03-05T11:52:21.000Z
Channel: Bartleby
Description: A researcher wants to asses the self-disciplinelevels among undergraduate and graduatestudents. A random sample of 300undergraduate students was selected withaverage score of 184 and standard deviation of16 ( group 1). Also , a random sample of 350g

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

Researchers are interested in the effect of pet companionship on depression in elderly adults. They randomly select 25 participants from the target population and record their depression scores before and after spending a month with a dog (a higher score indicates a higher level of depression). The researchers then compute the difference scores for each participant (difference after before). The mean of differences is - 1 and the standard deviation of differences is 2. Can the researchers conclude that there is an effect of pet companionship on depression in elderly adults? Conduct the appropriate statistical test (two-tailed) with a = .05. Based on the information provided above, which statistical test seems most appropriate? one sample t test O z test independent samples t test O dependent samples t test
It is known that, nationally, doctors working for HMOs average 13.5 years of experience in their specialties, with a standard deviation of 7.6 years. The distribution is a normal distribution. The executive director of an HMO in a western state is interested in determining whether or not its doctors have less experience than the national average. A random sample of 64 doctors from the HMO shows a mean of only 10.9 years of experience. State the research and null hypotheses to test whether or not doctors in this HMO have less experience than the national average at α = .05.
Researchers from a certain country were interested in how characteristics of the spleen of residents in their tropical environment compare to those found elsewhere in the world. The researchers randomly sampled 93 males and 107 females in their country. The mean and standard deviation of the spleen lengths for the males were 10.8 cm and 0.9 cm, respectively, and those for the females were 10.2 cm and 0.7 cm, respectively. At the 5% significance level, do the data provide sufficient evidence to conclude that a difference exists in the mean spleen lengths of males and females in the country? Click here to view page 1 of the table of critical values of t. Click here to view page 2 of the table of critical values of t. O E. Ho: H1 H₂ Hai Hg = H2 Compute the test statistic. =(Round to two decimal places as needed.) Determine the critical value(s). t= OF. Ho: H1 H₂ Ha: H1 H₂ 0 (Round to three decimal places as needed. Use a comma to separate answers as needed.) What is the conclusion of the…
During 2008, college work-study students earned a mean of $1478. Assume that a sample consisting of 25 of the work-study students at a large university was found to have earned a mean of $1503 during that year, with a standard deviation of $210. Formulate the null and alternative hypotheses that can be used to suggest that the average earnings of this university’s work-study students were significantly higher than the national mean
A personal trainer states that the distribution of running times (in seconds) for a 100-meter dash is normally distributed with a mean of 0.12 seconds and a standard deviation equal to 0.04 seconds. She wishes to improve running time by incorporating a set of breathing exercises into the daily workout. She randomly assigns some players to the new regimen in order to compare them to players who continue to follow the old workout. After six weeks, she records the average running time of the two groups of players. a. In the original distribution, what percentage of the players on the team run the 100-meter dash faster than 0.16 seconds? b. Define the independent and dependent variables. c. The personal trainer believes that the new breathing exercises have a significant improvement on running times. State the null and alternative hypotheses.
Researchers are interested in the effect of pet companionship on depression in elderly adults. They randomly select 25 participants from the target population and record their depression scores before and after spending a month with a dog (a higher score indicates a higher level of depression). The researchers then compute the difference scores for each participant (difference after before). The mean of differences is -1 and the standard deviation of differences is 2. Can the researchers conclude that there is an effect of pet companionship on depression in elderly adults? Conduct the appropriate statistical test (two-tailed) with a = .05. Should you reject or fail to reject the null hypothesis? Reject O Fail to reject
Suppose that El Camino is studying the average number of hours students study for classes per week. According to research from 2010 El Camino students spent an average of 21 hours a week studying for classes. El Camino wants to study if this average has changed. To do this they take a random sample of 81 current students and find that the average student spent 19.3 hours studying with a standard deviation of 6.4 hours. (Note: You may assume there are approximately 20,000 El Camino students). (a) Carry out a hypothesis test at α = .05 to test the claim that the average number of hours per week that El Camino students study has changed since 2010. (b) Describe what it would mean in this situation to make a Type I error (c) Describe what it would mean in this situation to make a Type II error (d) Construct a 95% confidence interval for the average number of hours studied by El Camino students per week. Make sure to interpret your interval.
Fran is training for her first marathon, and she wants to know if there is a significant difference between the mean number of miles run each week by group runners and individual runners who are training for marathons. She interviews 42 randomly selected people who train in groups and finds that they run a mean of 47.1 miles per week. Assume that the population standard deviation for group runners is known to be 4.4 miles per week. She also interviews a random sample of 47 people who train on their own and finds that they run a mean of 48.5 miles per week. Assume that the population standard deviation for people who run by themselves is 1.8 miles per week. Test the claim at the 0.01 level of significance. Let group runners training for marathons be Population 1 and let individual runners training for marathons be Population 2. Step 2 of 3 : Compute the value of the test statistic. Round your answer to two decimal places.
Bone mineral density (BMD) is a measure of bone strength. Studies show that BMD declines after age 45. The impact of exercise may increase BMD. A random sample of 59 women between the ages of 41 and 45 with no major health problems were studied. The women were classified into one of two groups based upon their level of exercise activity: walking women and sedentary women. The 39 women who walked regularly had a mean BMD of 5.96 with a standard deviation of 1.22. The 20 women who are sedentary had a mean BMD of 4.41 with a standard deviation of 1.02. Which of the following inference procedures could be used to estimate the difference in the mean BMD for these two types of women
According to a recent study published by the American Statistics for Educators Journal, statistics students spend, on average, 80 minutes a week playing video games. A certain instructor of statistics at WCC believes that WCC students spend less than this amount of time playing video games per week. To test his belief, he randomly samples 31 students and finds the sample mean to be 72 minutes with a standard deviation of 35 minutes. At the 0.05 level of significance, is there evidence to suggest that WCC students spend less than 80 minutes a week, on average, playing video games? Use the p-value approach. Define the parameter we are testing and setup a hypothesis to test the see if the statistics instructor is correct: Calculate the test statistics for this hypothesis test. What is the p-value for this hypothesis test?
The salaries of professional baseball players are heavily skewed right with a mean of $3.2 million and a standard deviation of $2 million. The salaries of professional football players are also heavily skewed right with a mean of $1.9 million and a standard deviation of $1.5 million. A random sample of 40 baseball players' salaries and 35 football players' salaries is selected. The mean salary is determined for both samples. Let -, represent the difference in the mean salaries for baseball and football players. Which of the following represents the shape of the sampling distribution for ,-7,? skewed right since the populations are both right skewed skewed right since the differences in salaries cannot be negative approximately Normal since both sample sizes are greater than 30 approximately Normal since the sum of the sample sizes is greater than 30
A researcher is interested in examining the effect of emotions on those that are convicted of a crime while under the age of 15. She decides to compare the empathy quotient (EQ) scores of those convicted of violent crimes to those convicted of non-violent crimes. A random sample of 35 violent offenders had a mean score of 33.5 and a standard deviation of 3.2, and another sample of 46 non-violent offenders had a mean of 37 and a standard deviation of 3.8. Also, suppose that equal variance cannot be assumed, but the populations are normal. If a higher EQ score indicated increased empathy, construct a 95% confidence interval for the difference in means. What is the critical value? What is the lower bound of the confidence interval? What can she conclude about the difference in empathy between the two groups?