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Hypothesis Testing

Statistics Question-Linear

A researcher wants to determine whether the number of minutes adults spend online per day is related to gender. A random sample of 315 adults was selected and the results are shown below. Test the claim that the number of minutes spent online per day is related to gender. Use α=0.05. Minutes Spent Online Per Day Gend

Hypothesis Tests and Test Statistic

1. (1 point) The Dick Tracy Co. has developed micro-miniaturized circuitry that will enable them to produce a wristwatch-sized video-telecommunicator. Research and development costs are believed to be high, and the company is uncertain whether it should proceed. The company has a strategic alliance with Cells-R-Us, a national pr

Z test for population proportion

It was claimed recently that more than 65% of high school students in the United States use computers for educational purposes. We wish to examine this claim. We choose a random sample of 180 U.S. high school students and find that 123 of these students use computers for educational purposes. Based on this, can we conclude, at t

Statistics - Hypothesis Testing and Profit Distribution

1. A manufacturing firm recruits 45 new sales staff, and sends each on one of two training courses. 25 attend course A, and 20 attend course B. The sales figures are then collected for the following six months and the following summary statistics are produced from profits X (in pounds) generated from these sales: (see attach

Statistics - Hypothesis tests...

Hypothesis tests for the correlation coefficient and the slope of the least-squares regression line The Cadet is a popular model of sport utility vehicle, known for its relatively high resale value. For a random sample of Cadets, each bought "new" two years ago and each sold "used" within the past month, the sample correlatio

Statistics of Plant Heights

Heights were measured for a random sample of 20 plants grown while being treated with a particular nutrient. The sample mean and sample standard deviation of those height measurements were 39 centimeters and 12 centimeters, respectively. Assume that the population of heights of treated plants is normally distributed with mea

Estimation and Test of Hypothesis

1. When the means of two unrelated samples are used to compare two populations, we are dealing with two dependent means ___ T/F 2. If standard deviation is unknown when completing a hypothesis test about the population mean, then the best estimate for the unknown standard deviation is s. _____ T/F 3. The number of d

P-value for Fast Food Companies

1. Determine the p-value for H0: p=.5 versus HA: p =/ (difference) .5 when n=225 and p^ =.54. 2. A fast food company uses two management-training methods. Method 1 is a traditional method of training and Method 2 is a new and innovative method. The company has just hired 36 new management trainees. 15 of the trainees are

Significance Levels, P-Values, and Confidence Intervals

You are investigating the flight characteristics of different kinds of birds. You collect a sample of 33 European swallows (Hirundo rustica) and measure their air-speed velocity in a borrowed wind tunnel. You find the mean air-speed velocity to be 11 meters/second with a standard deviation of 3 meters/second. You then collect a

Statistical Tests, Hypothesis Testing, p-Values, and Sample Size

1. Classify the following as independent or dependent samples: a. The effectiveness of two blood pressure medicines on two groups of patients. b. Measures of gas mileage and speed for a group of racecars. c. Scores of a group of nurses on the NCLEX nursing license exam. 2. Please answer the following. a. Expla

Null Hypothesis of M&M colors with ANOVA

The weights (in grams) of four different colors of M&M candies are given below, along with the mean weight and variance of each color, and the variance of the sample means. Use a one-way ANOVA at the 0.025 significance level to test the null hypothesis that the different color M&M candies have the same mean weight. Red Oran

Biostatistics in Genstat

1. (a) The medical literature suggest that the probability of a child contracting chickenpox (A) is 0.18; of contracting German measles (B), 0.12; and of contracting both, 0.07. i. Are the two events A and B mutually exclusive? Independent? Explain. ii. Find the probability that a child will contract at least one of the t

In this solution, the solution calculations are done using Excel. There are four tests of hypothesis regarding the population mean, the four standard deviations of the four samples are compared, and upper and lower control limits for the process are calculated.

Quality Associates, Inc, a consulting firm, advises its clients about sampling and statistical procedures that can be used to control their manufacturing processes. In one particular application, a client gave Quality Associates a sample of 800 observations taken during a time in which that client's process was operating satisfa

Hypothesis Tests Multiple Choice

See the attached file for the proper symbols and formatting. Part I T/F & Multiple Choice 1. An estimator is consistent if, as the sample size decreases, the value of the estimator approaches the value of the parameter estimated. ____ T/F 2. For a specific confidence interval, the larger the sample size, the smaller

Population Means testing :True for false question

Please indicate either TRUE or FALSE for the questions. If you indicate FALSE as your answer, briefly explain why the statement is false. 1. In order to compare the characteristics of two different populations, a sample should be extracted from each population. 2. When two populations are compared and samples taken fr

Variance and Sketching P-Values

1. In this test, the variance is known. Find the p-value of the test to 4 decimals, if the obtained value of the test statistic is 2.34. Make a sketch and represent the p-value. H_o : Mu = Mu_o H_a : Mu ,not = to, Mu_o 2. In this test, the variance is known. Find the p-value of the test to 4 decimals, if the obtained valu

Hypotheses test for the United States Department of Labor

In 2001, the U.S. Department of Labor reported the average hourly earnings for U.S. production workers to be $14.32 per hour. A sample of 60 production workers during 2003 showed a sample mean of $14.68 per hour. Assuming the population standard deviation σ = $1.55, can we conclude that an increase occurred in the mean hourly e

Calculations for hypothesis testing problems

The Employment and Training Administration reported the U.S. mean unemployment insurance benefit of $238 per week (The World Almanac 2003). A researcher in the state of Virginia anticipated that sample data would show evidence that the mean weekly unemployment insurance benefit in Virginia was below the national level. For a sam

P-value and test statistic for Haug Motor Company

Marketing executives at Haug Motor Company, producers of the world's most imposing SUVs, are planning their sales campaign for a new model, the 6000 lb. Enviroraptor MPG-8?. They are staking their hopes on the belief that the average American is more interested in personal aggrandizement than in the environment or public safety.

Test of Hypothesi: Mean Waiting Time

The Restaurants McBurger says that the waiting time for customers is 3 minutes with a standard deviation of population 1 minute. The quality control department found in a sample of 50 clients that the average waiting time was 2.75 minutes. With a significance level of 0.05. Can conclude that the waiting time is less than 3 minut

RES 342 problems

1. List the five steps of solving a statistical problem 2. Write a hypothesis test (H1 and Ha) statement for the following: Many people eat cookies with milk. Suppose a cookie company is concerned that the cookie equipment may not be functioning properly when filling 32-ounce bags. 3. Use the same information

Applying the P-Value Approach

Please answer the following question using the P value approach. Please describe your answer in detail. The answer details are important to my understanding the P value concept. A sample of 40 recovering alcoholics was given the State-Trait Anxiety Inventory Test (STAI). The state anxiety score showed a mean of 38 and a sta

P value for Hypothesis testing .

Please answer the following question using the P value approach. Please describe your answer in detail. The answer details are important to my understanding the P value concept. Q1) The mean number of calories per 6-ounce can of tomato paste is supposed to be 150. A weight watchers group thought that was larger

Level of risk for income tax agencies

The director of an income tax agency hires four college students, who are business majors, to help prepare taxes during the busy season. To see whether he should hire any of them for the next year, he samples how long it takes each new employee to prepare similar tax returns for 10 randomly selected customers. Below is a table o

Hypothesis testing (in Excel and show work)

10.23: Examine the data below showing the weights (in pounds) of randomly selected checked bags for an airline's flights on the same day. (a) At a = .05, is the mean weight of an international bag greater. Show the hypotheses, decision rule and test statistic. (b) At a= .05, is the variance greater for bags on an internationa

Traditional Hypothesis Testing Method

Conduct a hypothesis test for each problem, using the traditional method. 1. A random sample of 56 departing flights at an airport over a 3-month period had a mean wait of 14.2 minutes between boarding and takeoff, with a standard deviation of 4.53 minutes. At the same airport, a random sample of 81 incoming flights over

Hypothesis Testing of Soft Drink Filling Machine

A soft drink filling machine, when in perfect adjustment, fills the bottles with 12 ounces of soft drink. Any over filling or under filling results in the shutdown and readjustment of the machine. To determine whether or not the machine is properly adjusted, the correct set of hypotheses is H0: m = 12 Ha: m=/ 12 TRUE/ FA

Statistics of Ear Infections in Elementary School

Many elementary school students in a school district currently have ear infections. A random sample of children in two different schools found that 16 of 42 at one school and 21 of 36 at the other had this infection. At the .05 level of significance, is there sufficient evidence to conclude that a difference exists between the

Sample size and Hypothesis testing problems

Assignment 3 The Precision Scientific Instrument Company manufactures thermometers that are supposed to give readings of 0°C at the freezing point of water. Tests on a large sample of these thermometers reveal that at the freezing point of water, some give readings below 0°C (denoted by negative numbers) and some give readi