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Hypothesis Testing

Hypothesis test: Difference in proportions problem

A sample of high school seniors showed that 18 of 60 who owned PlayStation 3 spent more than an hour a day playing games, compared with 32 of 80 who owned Xbox 360. Is there a significant difference in the population proportions at alpha = .10?

Hypothesis testing standard deviation with one sample. Minitab

Hypothesis testing with one sample Testing a Claim About a Standard Deviation or Variance Systolic Blood Pressure for Women: Systolic blood pressure results from contraction of the heart. Based on past results from the National Health Survey, it is claimed that women have systolic blood pressures with a mean and standard de

Hypothesis Testing: Female Blood Pressure

Testing a Claim About a Standard Deviation or Variance Systolic Blood Pressure for Women: Systolic blood pressure results from contraction of the heart. Based on past results from the National Health Survey, it is claimed that women have systolic blood pressures with a mean and standard deviation of 130.7 and 23.4, respective

Tests of means and proportions and Tests of variances

Assignment for EText TESTS OF MEANS AND PROPORTIONS 9.52 At Ajax Spring Water, a half-liter bottle of soft drink is supposed to contain a mean of 520 ml. The filling process follows a normal distribution with a known process standard deviation of 4 ml. (a) Which sampling distribution would you use if random samples of 10 bot

Significance of the Difference Between Two Sample Means

I need help with this problem. I already know the answer. I am confused between the lectures, textbook, and work text. Can you show me, the old fashioned way (not Excel, SPSS or any other software to generate the answer), I need the formulas to show how to come up with the correct answer? Here is the problem: An experim

Auditor review

An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the aver

Hypothesis Testing

The Web-based company Oh Baby! Gifts has a goal of processing 95 percent of its orders on the same day they are received. If 485 out of the next 500 orders are processed on the same day, would this prove that they are exceeding their goal, using α = .025?

Coin flip ...

A coin was flipped 60 times and came up heads 38 times. (a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. (b) Calculate a p-value and interpret it.

Graduate Program Applicants: Nondirectional Test

Over a 20 year period, the average grade point average of applicants to our graduate program has been found to be 3.27. This year the mean grade point average of the 57 students applying to our graduate program is 3.53, with a standard deviation of 0.29. Test the hypothesis that the current sample came from a population in whi

Coin Toss: Hypothesis Testing

A coin was flipped 60 times and came up heads 38 times. (a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. (b) Calculate a p-value and interpret it.

Determining Significance: Chronic Fatigue Syndrome Treatment

Treating Chronic Fatigue Syndrome Patients with chronic fatigue syndrome were tested, then retested after being treated with fluorocortisone. Listed below are the changes in fatigue after the treatment (based on data from "The Relationship Between Neurally Mediated Hypertension and the Chronic Fatigue Syndrome" by Boi Holaigah,

Scatter plot, correlation coefficient, and a hypothesis test

(a) Make a scatter plot of the data. What does it suggest about the correlation between X and Y? (b) Use Megastat or Excel to calculate the correlation coefficient. (c) Use Excel to find t.05 for a two-tailed test. (d) Calculate the t test statistic (e) Calculate critical value of ra. (f) Can you reject p=0? Orders(X)

Hypothesis test for a sample mean

The mean wages paid to Americans between the ages of 45 and 64 across all demographics in the United States is $38,740 with a standard deviation of $156. We took a sample of 31 workers between the ages of 45 and 64. They had a mean earned wages of $33,298. At the 0.05 significance level can we conclude does the sample show that

Relationship between levels of significance and rejecting the null

1-The lower the level of significance, the harder it is to reject the null. In sum, you want to be REALLY sure that your alternative hypothesis is correct, so if you use a low significance level (say, .01), then you would only reject the null if you're REALLY sure about the outcome. Most use a .05 level of significance, which

Hypothesis Testing for prospective cohort study

A recent prospective cohort study analyzed the effect of calcium plus vitamin D supplement use on the development of osteoporosis (weak and brittle bones). QUESTION 11 What are the null and alternative hypotheses being investigated in this study? (Be sure to specify the exposure-outcome association under study along with t

Stock Market: Hypothesis Test for Equal Population Variance

Each day the major stock markets have a group of leading gainers in price (stocks that go up the most). On one day the standard deviation in the percent change for a sample of 10 NASDAQ leading gainers was 15.8. On the same day, the standard deviation in the percent change for a sample of 10 NYSE leading gainers was 7.9 (USA Tod

Hypothesis test: population proportion

CherryBerry Soda, Inc. claims that 15 percent of the population can identify its products. In efforts to boost their identity, CherryBerry employs a famous spokesperson to advertise. A survey is then taken to assess the results of the ad campaign. The results show that 17 percent of the 1000 respondents can identify CherryBerry

Hypothesis Testing: Mean Time to Learn a New Software Program

A recent article in a computer magazine suggested that the mean time to fully learn a new software program is 40 hours. A sample of 100 first-time users of a new statistics program revealed the mean time to learn it was 39 hours with the standard deviation of 8 hours. At the 0.05 significance level, can we conclude that users le

Hypothesis Test for Houses with Pools in Southern California

For several decades, it was a common practice in Southern California for houses to be built with pools in the backyard (as any airplane flight which ends at a Southern California airport will reveal). Now, however, that practice may be changing, possibly because of the recent demand for landscaped homes, which experts believe he

Using a hypothesis test to determine if unsafe Radon levels vary by region.

Radon is a gas produced when radium decays, and it can enter homes where it can become a health threat. Among 186 homes in Hyde Park, New York (home of Franklin D. Roosevelt), 16% were found to have unsafe radon levels (above 4 picocurries per liter). Among 237 homes in LaGrange, New York (home of the author), 19% were fou

Hypothesis Test: Difference of Proportions

The general social survey is an annual survey given to about 1,500 U.S. adults selected at random. Each year, the survey contains several questions meant to probe the respondents' views of employment. A recent survey contained the question "How important to your life is having a fulfilling job?" Of the 264 college graduates su

Testing of Hypothesis: Example Problem

A researcher has observed independent samples of females and males, recording how long each person took to complete his or her shopping at a local mall. The respective times, in minutes, are listed in file xr11072. Using the 0.025 level of significance in a one-tail test, would females appear to exhibit more variability than mal

Hypothesis Tests for Two Independent Samples

(Please see attached document for full questions). 1. In two independent samples from populations that are normally distributed, x1-bar = 35.0, s1 = 5.8, n1 = 12 and x2-bar = 42.5, s2 = 9.3, n2 = 14. Using the 0.05 level of significance, test H0:mu1 = mu2 versus H1:mu1 ≠ mu2. 2. For the following independent random sampl

Hypothesis test for difference in means across populations

A sample of 40 investment customers serviced by an account manger are found to have had an average of $23,000 in transactions during the past year, with a standard deviation of $8500. A sample of 30 customers serviced by another account manager averaged $28,000 in transactions, with a standard deviation of $11,000. Assuming th