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Hypothesis Testing

Level of Significance and Hypothesis Testing

See the attached file. 2(a). In the context of hypothesis test, state what is meant by: (i). Type I error (ii). Type II error (iii). Power of the test What connections are there, if any, between them? (b). The sales and marketing team in motor business is investigating the quality of second hand cars. One indicator o

Two or More Sample Hypothesis Testing - Multiple Choice

I Completed the first half, but I am struggling with the questions below. They are multiple choice. Objective: Apply hypothesis testing to different populations and samples in business research situations. 5. One characteristic of any Student's t distribution is a. It is right skewed. b. As n increases, the t-di

Independent Measures Comparing Three Treatment Conditions

1. A researcher conducts an experiment comparing three treatment conditions. The data consist of n=20 scores for each treatment condition. a. If the researcher used an independent-measures design, then how many individuals were needed for the study and what are the df values for the F ratio? b. If the researcher used a repeate

Elementary Statistics

1. Use a P- value to test the claim about the population mean μ using the given sample statistics. State your decision for α = 0.05 Claim: μ ≠ 230; Sample statistics: x (bar) = 216.5, s = 17.3, n = 48 = _ 2. If X =5.2, R =.3,and n=4, and if specifications are (4.6, 5.8), is the process capable? Show work.

Hypothesis Testng: Wilcoxon Rank Sum Test

1) Two gasoline additives will be tested to determine their impact on miles per gallon for passenger cars. In the experiment, each car was tested with both gasoline additives. Use a level of significance α = 0.05 and the rank sum test Wilcoxon test whether any significant difference in the two additives.

Case Study 11.1 (Testing hypothesis)

Sample Item Original Supplier New Supplier 1 0.374 0.391 2 0.387 0.375 3 0.359 0.365 4 0.391 0.360 5 0.390 0.366 6 0.361 0.378 7 0.376 0.377 8 0.371 0.364 9 0.373 0.332 10 0.364 0.343 11 0.390 0.378 12 0.384 0.401 13 0.384 0.382 14 0.383 0.381 15 0.381 0.363 16 0.369 0.371 17 0.361 0.352 18 0.376 0.393 19 0.38

Business Research

The maker of refrigerators buys bolts from two suppliers, and it is very important that the mean widths of the bolts received from both suppliers are equal since they must be used interchangeably. The refrigerator maker receives a large shipment of volts from each supplier and draws a random sample of 49 bolts from each shipmen

Null and Alternative Hypotheses and Levels of Significance

A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evide

Stem Cell Transplant & Worker Motivation Problems

See attached file for data. 10.28 Multiple myeloma, or blood plasma cancer, is characterized by increased blood vessel formulation (angiogenesis) in the bone marrow that is a prognostic factor in survival. One treatment approach used for multiple myeloma is stem cell transplantation with the patient's own stem cells. The fo

'Statistics for Managers' using Excel 5th edition: T F questions

True or False: The t distribution is used to develop a confidence interval estimate of the population mean when the population standard deviation is unknown. True or False: The confidence interval estimate of the population proportion is constructed around the sample proportion. True or False: The F test used for testing t

Hypothesis Testing -Number of Seniors Planning to Attend College

Results from previous studies showed 79% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5%

Null and alternate hypothesis

1.A machine produces 5-inch nails. A sample of 12 nails was selected and their lengths determined. The results are as follows: 4.94 4.94 5.07 4.91 4.98 5.00 4.94 5.09 5.00 4.92 5.08 5.06 Assuming that a = 0.10, test the hypothesis that the population mean is equal to 5. ?State the null and alternate hypotheses ?&

Hypothesis testing: Coin flip example

A coin was flipped 100 times and came up heads 59 times and tails 41 times. The expected outcome was to land on heads or tails 50 times each. Do a hypothesis test to test the null that the percentage is equal to the expected as opposed to the alternative that it is greater or lesser or equal to the expected value, depending on

Sample Hypothesis Testing

Objective: Identify the formal hypothesis testing process. 1. If a null hypothesis is not rejected at the 0.10 level, it may be rejected at the 0.05 level. a. 0 True b. 0 False Objective: Perform a hypothesis test of one proportion. 2. The Roman Senate has become concerned about the loyalty of the army in Gaul com

Hypothesis Testing: Difference in the Means of the Two Groups

You are given the following data. Test the claim that there is a difference in the means of the two groups. Use = 0.01. Group A Group B x1 = 5 x2 = 7 s1 = 12 s2 = 18 n1 = 63 n2 = 86 · State the null and alternate hypotheses · Determine which test statistic applies, and calculat

The solution to Statistics: Hypothesis Testing

The pulse rates below were recorded over a 30-second time period, both before and after a physical fitness regimen. The data is shown below for 8 randomly selected participants. Is there sufficient evidence to conclude that a significant amount of improvement took place? Assume pulse rates are normally distributed. Test using =

Hypothesis Testing problem

A machine produces 5-inch nails. A sample of 12 nails was selected and their lengths determined. The results are as follows: 4.85 4.80 4.89 4.82 4.94 4.96 4.96 4.83 4.80 4.84 4.95 4.88 Assuming that = 0.10, test the hypothesis that the population mean is equal to 5. · State the null and alternate hypothe

Hypothesis Testing - Critical Value, P-value

In 2001, an estimated 78% of executives believed that age bias was a serious problem. In a 2004, 82% of the executives surveyed considered age bias a serious problem. The sample size for the 2004 study was not disclosed. Suppose 50 executives were surveyed. 1. At the 0.05 level of significance, use the 6-step critical value a

Find the P-value for the indicated hypothesis test

In a sample of 47 adults selected randomly from one town, it is found that 9 of them have been exposed to a particular strain of the flu. Find the P-value for a test of the claim that the proportion of all adults in the town that have been exposed to this strain of the flu is 8%.

F-test and confidence interval

Consider the following Hypothesis Testing: H0: δ1² = δ2² Ha: δ1² ≠ δ2² The sample size for sample 1 is 25, and for sample 2 are 21. The variance for sample 1 is 4.0 and for sample 2 is 8.2 a) at the confidence level of 0.98, what is your conclusion of this test? b) What is the confidence

Critical value/ p-value

The owner of a restaurant has just changed the delivery process in order to reduce the mean time between the order and completion of delivery from the current 25 minutes. In the past, the population standard deviation has been 6 minutes. A sample of 36 orders under the new delivery process results in a sample mean of 22.4 minu

Rejection Method and Interpret Results: Example Problem

A job placement director claims that the average starting salary for nurses is $24,000. A sample of 35 nurses has a mean of $23,450 and a standard deviation of $400. Is there enough evidence to reject the director's claim at alpha = 0.05? Use the rejection region method and provide an interpretation of the results.

Raw Data

Directions: Use the attached set of raw data to complete the following tasks. For tasks 1 through 4 please focus on New Mexico highway fatalities.. In task five you will be comparing New Mexico and U..S. highway fatalities. All work must be done by hand. You may use a calculator but only as an aid.. You must demonstrate tha

Hypothesis Testing of Variance & Sample size

Question 5 Use the traditional method to test the given hypothesis. Assume that the population is normally distributed and that the sample has been randomly selected A machine dispenses a liquid drug into bottles in such a way that the standard deviation of the contents is 81 milliliters. A new machine is tested on a sample