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Hypothesis Testing

Random Sample - Test Scores

In the past, 38% of all students pass the state high school exam on their first try. A school posts a first time passing rate of 56%. If the school had a sample size of 324, is the school's 56% really any different that the state's 38%?

Hypothesis Test

The scores of 133 males and 162 females on a test that measures a person's feelings are shown in the table below. Your conjecture is the "the feelings" of males and females in the population are different. Run a hypothesis test to check this proposition. Group Sample size x-bar Standard Deviation of the samp

proportion testing for SAT scores

Two high school principals are arguing about who has the better school. This principal for Hard Rock High, Desi Mall, draws a random sample of 100 of her seniors and finds that 75% scored above 650 on the math portion of the SAT. Sharon N. Formation, the principal of Preppy Magnet School, drew a sample of 25 students and found t

Description of Statistics - Hypothesis Test

North Carolina State University looked at the factors that affect the success of students in a required chemical engineering course. Students must get a C or better in the course in order to continue as chemical engineering majors. There were 65 students from urban or suburban backgrounds, and 52 of these students succeeded. Ano

Breathing Pattern Statistics

#4 In a study of hypnosis, breathing patterns were observed in an experimental group of subjects in a control group. The measurements of total ventilation (liters of air per minute per square meter of body area) are shown below. We want to know whether the groups follow the same distribution. Unfortunately, we cannot assume

Statistics on Heart Disease

#3 Heart disease patients often experience spasms of the coronary arteries. Because biological amines such as serotonin may play a role in these spasms, a research team measured serotonin levels post-mortem from patients who died of heart disease and from a control group that died of other causes. The data are summarized in t

Predict the number of ovarioles from the pupal size

Webber studied the relationship between pupal weight (in milligrams) and the number of ovarioles in females of the blowfly. We want to predict the number of ovarioles from the pupal size. (see table "Pupae" in Excel) 9.1 What test or procedure should be performed? 9.2 Perform the test and assess its significance. 9.3

State Null and Alternate Hypothesis

1. A sample of 64 observations is selected from a normal population. The sample mean is 216, and the sample standard deviation is 15. Conduct the following test of hypothesis sing the .03 significance level. H0: µ ≥220 H1: µ < 220 a. State the null and the alternate hypothesis b. State the decision rule c. Compute

homogeneity of variance assumption

1. Describe the general characteristics of a research study for which an independent-measures t would be the appropriate test statistics 2. What is measured by the estimated standard error that is used for the independent-measures t statistic? 3. Describe the homogeneity of variance assumption, and explain why it is import

Statistical Analysis of Quaker Oats

Quaker Oats is contemplating changing the shape of its box from the quaint cylinder presently in use. Different random samples were selected from five stores of similar size in the same region, and one of the candidate boxes was substituted for the cylinder for several days. The following results were obtained for the total numb

Various Statistics Questions

1. Based on the specific question under study, how can one always determine which is the null hypothesis (H0) and which is the alternative hypothesis (H1). 2. A consumer advocate tests the claim that the Toyota Corolla actually delivers less than 32 mpg (as stated on the advertisements). So, we have:

Statistics - True and False

1. Degrees of freedom for the independent-measures t statistic can be computed as df = n 1 + n 2 - 2. True False 2. For an independent-measures study comparing two samples with n = 8 in each sample, the t statistic would have df = 15. True False 3. Which of the following rese

Single-tailed, 2-sample mean, t-test

Ten automobiles were driven on a measured test track - once with standard gasoline with no additive and once with an additive supposed to increase miles per gallon (mpg). The results are given below: mpg / car # 1 2 3 4 5 6 7 8 9 10 without additive 19 22 25 18 26 21 23 28 24 24 with additive

Hypothesis Testing

Safe T cigarettes claim that their product has "low tar." Government standards are that this claim is invalid if there are more than 13.5mg tar per cigarette. A sample of five Safe T cigarettes gives 14.0, 13.7, 13.9, 13.8, and 14.1 mg of tar. Is there sufficient evidence at the alpha=0.05 significance level for the governmen

Statistics Clarification

1. The dependent and independent variables as they are not correct. Please advise. 2. Also, need advise on formulating the research question and developing the hypotheses Equation: The random sample population is 500 people who shop for workout programs and equipment. The sample mean of those shopping is that they spend an

Statistics and Single-Sample T-test

Equation: The random sample population is 500 people who shop for workout programs and equipment. The sample mean of those shopping is that they spend an average of $250.00 per purchase and perchance at least 2 to 3 items for working out and weight lost Assume that the population of consumers is normally distributed with mean M

Interpretation of a Statistical Test

Please help me with the following statistical problem: A sample is taken prior to a major election of likely voters. The null hypothesis is that the votes will be split 50/50. One candidate gets 54% of the support in the sample and the p-value for this sample is calculated to be 0.12. What is the correct interpretation o

Experimental Design and Analysis

Given the following information about a hypothesis test of the difference between 2 means based on independent random samples, what is the correct rejection region at a significance level of .05? Ha: Ua> Ub x1-112, x2=9 s1=4, s2=2 n1=13, n2=10

Hypothesis Testing Verbal Results and Recommendations

Describe the results of the test and explain how the use of this hypothesis testing can be used to evaluate solutions to your research issue. Steadily rising transportations expend larger portions of the consumer budget. This test is specifically targeting funds spent on public transportation, gasoline, or toll fees. In orde

Hypothesis testing problem

This is a hypothesis testing problem. I have set up the null and alternative hypotheses. I need assistance in completing the requirements located at the bottom of the document. Steadily rising transportations expend larger portions of the consumer budget. This test is specifically targeting funds spent on public transportatio

Hypothesis Testing for One Population Mean

The weights of 9 of managers at Company X are determined. They have a mean of 70.2 Kg, and a standard deviation of 1.5 Kg. Use a 0.01 significance level to test the claim that managers at Company X have weights with a mean that is greater than the mean of 63.6 Kg for managers from the general population. Given that there are

Hypothesis Testing for One Population Mean of Systolic Blood Pressure

Working at Company X is very stressful for any human being. Medecines Sans Frontires stepped in to see if there is any possible violations of human rights at the notorious Company X. They picked one hapless employee and have a group of 14 volunteer nurses measured his systolic blood pressure and obtained the following results

Hypothesis Testing - Brands

I need assistance testing a hypothesis and identifying the solution/variance, details are included in the attachment. A driving machine was employed to hit a sample of 41 each of two different brands of golf balls using the same force each time. The research team then measured the distance between the point of impact and wher

Basic Statistics in PHStat..

- Using PHSTat - Send Excel + Paste into Word also * Must write out a NULL & HYPOTHESIS and include BUT WHAT DOES THIS MEAN TO A MANAGER?? See attached file for solution template.

10 Multiple Choice Questions in Statistics- Hypothesis

1. Whenever your decision is to reject the null hypothesis, there is a risk of a Type I error. True False 2. A Type I error occurs when you conclude that a treatment effect exists, but the treatment has no effect. True False 3. The critical region consists of extreme sample values

Business Statistics using PHSTAT add-in

See attached: Must use Excel with the PHSTAT add-in, and then paste all into MS Word. The manager of a paint supply store wants to determine whether the amount of paint contained in 1-gallon cans purchased from a nationally known manufacturer actually averages 1gallon. It is known from the manufacturer's specifications that t

Important information about Testing hypotheses by the Excel

Shank's Inc., a nationwide advertising firm, wants to know whether the size of an advertisement and the color of the advertisement make a difference in the response of magazine readers. A random same of readers is shown ads of four different colors and three different sizes. Each reader is asked to give the particular combinatio

Hypothesis testing - Confidence Intervals

Problem. Test scores for class are: 93%, 77%, 90%, 85%, 86%, 81%, 88% At a = .10 can it be said that the standard deviation is greater than 4%. State (1) the null hypothesis (2) determine the critical value (3) determine the test statistic (4) State decision and summary Also, construct the 90% confidence interval for th