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Hypothesis Testing

Find P-Value and Sketch Graph

13.6) Explain why the null hypothesis for a significance test is rejected when the p-value is small rather than when it is large. 13.12) Find the p-value and draw a sketch showing the p-value area for the following situation in which the value of t is the test statistic for the hypothesis given: a.) Ho?:µ=µ0, Ha: µ>µ0

Statistics M&M project to test proportion of red and brown candies

See attached files. Using the methods in Section 8.4, test the hypothesis (± = 0.05) that the population proportions of red and brown are equal (pred = pbrown). You are testing if their proportions are equal to one another, NOT if they are equal to one another AND equal to 13%. NOTE: These are NOT independent samples, but

Parametric and Non-Parametric Hypothesis Tests

Re-analyze the data in Table 8.18 using nonparametric methods. Assume the samples are unpaired. Table 8.18 Birthweights in a clinical trial to test a drug for preventing low-birthweight deliveries Baby weight (lb) Patient number Treatment Group Control Group 1 6.9 6.4 2 7.6 6.7 3

Test effect of cognitive psychotherapy on positive self-regard

17. A researcher studies the effect of cognitive psychotherapy on positive self-regard. The number of positive statements made about oneself is recorded for each participant during the first meeting. After 8 weekly therapy sessions, the measures are repeated for each person. For the following data. Participant before trea

chart and data analysis of student absences at local middle schools

You will be acting as a community health department investigator who has been hired to look into a mysterious pattern of student absences at some local middle schools in your area. Start here by reading a memo from your boss by clicking on the Memo icon below. This memo outlines the basics of the problem for you. Luckily, yo

At what sigma level is this process operating?

The Wall Street Journal reported on February 15, 2000, that about 750,000 airplane components are manufactured, machined, or assembled for Boeing Co. by workers from the Seattle Lighthouse for the Blind. A Boeing spokeswoman noted that the parts have an "exceptionally low" rejection rate of 1 per 1,000. At what sigma level is th

Random Sample, Statistical Evidence

1. (a) A random sample of n = 12 E-glass fiber test specimens of a certain type yielded a sample mean interfacial shear yield stress of 34.8 and a sample standard deviation of 4.1. Assuming that interfacial shear yield is normally distributed, compute a 98% C.I. for the true average stress. (Ref: â?? On Interfacial Failure in N

5 Step Hypothesis Test

Assume that a simple random sample is selected from a normally distributed population. Use either the P-value method or the traditional method of testing hypotheses. Listed below are birth weights (in kilometers) of male babies born to mothers on a special vitamin supplement (based on data from the New York State Department

Test hypothesis that hearing is better after a large meal

A researcher theorized that people can hear better when they have just eaten a large meal. 6 individuals were randomly assigned to eat either a large meal or a small meal. After eating the meal, their hearing was tested. The hearing ability scores (high #s indicate greater ability) are given below. Using the.05 level, do the res

Important information about Normal Probability & Hypothesis Testing

Please use Excel and explain which test you use for problem 2 and 3 (t test, ANOVA, two tail or one tail...etc) 1. a. The score on the entrance exam at a well-known, exclusive law school are normally distributed with a mean score of 200 and a standard deviation equal to 50. At what value should the lowest passing score be s

Hypothesis Testing of Variance (F Test)

A manufacturing process drills holes in sheet metal that are supposed to be .5000 cm in diameter. Before and after a new drill press is installed, the hole diameter is carefully measured (in cm) for 12 randomly chosen parts. At ? = .05, do these independent random samples prove that the new process has smaller variance? Show the

Hypothesis Testing, Test statistic, Z or T test

1) The owner of a local night club has recently surveyed a random sample of n=250 customers of the club. She would now like to determine whether or not the mean age of her customers is over 30. If so, she plans to alter the entertainment to appeal to an older crowd. If not, no entertainment changes will be made. If so, she plan

Statistics 100 - 25 multiple choice

Also see attached file. 1) The owner of a fish market has an assistant who has determined that the weights of catfish are normally distributed, with mean of 3.2 pounds and standard deviation of 0.8 pound. If a sample of 16 fish is taken, what would the standard error of the mean weight equal? 0.003 0.05

Construct hypothesis, random variable, p-value, ANOVA

Statistics Chapter Review Questions For full credit, show all work and it must be clear; final answers must be clear as well. For questions that require a hypothesis test, clearly state H0 , H1,, your conclusion as a sentence, and the reasoning and computations behind your conclusion. Question 3: Eight samples of

Hypotheisis testing problems 37, 41, 43, 53, 55

37.) A study found that in 2005, 12.5% of U.S. workers belonged to unions. Suppose a sample of 400 U.S. workers is collected in 2006 to determine whether union efforts to organize have increased union membership. A.) Formulate the hypotheses that can be used to determine whether union membership increased in 2006 B.) If th

Hypothesis testing using P Value Format

Hypothesis Testing using only P value format. Do not copy and paste all the results from the hypothesis test, you are the expert, only include critical metrics from the test results. Most air traffic passenger use e-tickets. Electronic ticketing allows passengers not worry about paper tickets and it reduces the airlines co

Hypothesis Testing of a Random Sample Size of 64

See the attached file. It is desired to test H0: u=50 against H1: u<50 using alpha=0.1. The population in question is uniformly distributed with standard deviation 20. A random sample of size 64 will be drawn from the population. a) Find beta for each of the following values of the population mean: 49, 47, 45, 43 and 41 b)

5 Step Hypothesis Test

Here are heart rates for a sample of 30 students before and after a class break. At alpha =.05, was there a significant diffeence in the mean heart rate? (a) State the hypotheses. (b) State the decision rule and sketch it. (c) Find the test statistic (d) Make a decision. (e) Find the p-value

5 Step Hypothesis Test

A recent article in Vitality magazine reported that the mean amount of leisure time per week for American men is 40.0 hours. You believe this figure is too large and decide to conduct your own test. In a random sample of 60 men, you find that the mean is 37.8 hours of leisure per week and that the standard deviation of the sampl

5 Step Hypothesis Test for Bellevue Steel

The production manager at Bellevue Steel, a manufacturer of wheelchairs, wants to perform a second analysis of the number of defective wheelchairs produced on the day shift and afternoon shift. A sample of the production from 6 day shifts and 8 afternoon shifts revealed the following number of defects. At the 0.05 significanc

Hypothesis Testing of Mean: BMI

Identify the null and alternative hypothesis, test statistic, P-value,critical values and state the final conclusion that addreses the original claim: The trend of thinner Miss America winners has generated charges that the contest encourages unhealthy diet habits among young women. Listed below are body mass indexes (BM) fo

Hypothesis test for mean spending habits of $375

Families of size 4 spent a population mean of $360 on a visit to an amusement park, standard deviation of $50 in October 2000. Operators want to know whether families will spend more in 2001. In an April exit poll, 64 randomly selected families of size 4 were interviewed with the average amount spent by families in the sample

Statistics Problems

2. For each of the following, indicate whether the factor influences the numerator or denominator of the z score and determine whether the effect would be to increase the value of z (further from zero) or decrease the value of z (closer to zero). In each case, assume that all other components of the z score remain constant. a

Hypothesis Testing of Mean & Proportions

For the following four problems: 1. State the Null Hypothesis and the Alternative Hypothesis 2. Determine the test statistic. 3. Determine the P-value 4. Make a decision regarding the hypotheses based on the P-value and the Level of Significance. 1. In a recent year, some professional baseball players complained that u

5 Step Hypothesis Test

The following data represents the running time of films produced by 2 motion picture companies. Assume these are independent samples Company Time (in minutes) Company 1 102 86 98 109 92 Company 2 81 165 97 134 92 87 114 Test the null hypothesis that the average running time of th

Upper and lower confidence intervals: Water treatment example

Most water treatment facilities monitor the quality of their drinking water on an hourly basis. One variable monitored is pH, which measures the degree of alkalinity or acidity in the water. A target pH level is 8.5. pH values below 8.5 is acidic and above 8.5 is alkaline, both of which are bad for health. A random sample of

Business Statistics with 95% confidence intervals

1. Determine the minimum required sample size if you want to be 95% confident that the sample mean is within 3 units of the population mean given sigma = 7.8. Assume the population is normally distributed. 2. A manufacturer claims that the mean lifetime of its fluorescent bulbs is 1050 hours. A homeowner selects 40 bulbs and

Short Feedback

1. describe the "third variable problem" as it relates to correlation and provide an example of how you might see this played out in your own field. 2. How does hypothesis testing contribute to the scientific knowledge base? Now that you have a general understanding of hypothesis testing, provide an example of how you might