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Hypothesis Testing

Inference

One factor in low productivity is the amount of time wasted by workers. Wasted time includes time spent cleaning up mistakes, waiting for more material and equipment, and performing any other activity not related to production. In a project designed to examine the problem, an operations management consultant took a survey of 200

restaurant site is acceptable based on pedestrian traffic.

A fast food franchiser is considering building a restaurant at a certain location. Based on financial analyses, a site is acceptable only if the number of pedestrian passing the location averages more than 100 per hour. The number of pedestrians observed for each of 40 hours was recorded and stored in the attached excel file .

Z-estimate

In an attempt to reduce the number of person-hours lost as a result of industrial accidents, a large production plant installed new safety equipment. In a test of the effectiveness of the equipment, a random sample of 50 departments was chosen. The number of person-hours lost in the month prior to and the month after the install

Expectation and Hypothesis Testing

4. An experiment is set to test the hypothesis that a given coin is unbiased. The decision rule is the following: Accept the hypothesis if the number of heads in a sample of 200 tosses is between 90 and 110 inclusive, otherwise reject the hypothesis. a) Find the probability of accepting the hypothesis when it is correct.

Statistics problems

Please explain fully, using Excel when necessary. These questions were addressed once already, but they were not explained in a way in which they could be fully understood. Please detail each step. 1) A publisher is considering three different covers for a new magazine. A random sample of 90 people are asked to pick their fa

General Statistics P-Value and Significance Levels

Please use Excel when necessary: 1) When the p-value is smaller than the significance level: a) A type 1 error is committed b) A type 11 error is committed c) The null hypothesis is rejected d) The critical value is correct. Problem # 2) The coefficient of correlation between the variables X and Y was computed to be -0.6

No Differences Between the Two Groups of Subjects

A) Analyse the data below to test the hypotheses that there are no differences between the two groups of subjects in terms of their walking time to exhaustion (in seconds) and ratings of perceived exertion (RPE) after 8 minutes of walking. Healthy subjects --------------------------------------------------------------------

Biopstatistics Problem

I hope you can help me with this problem. I have 2 questions regarding this study. 1) I have heard from my teacher that there is a 7th null hypothesis hidden in the text for this study. The first 6 are presented in the tables. WHAT IS THE 7TH NULL HYPOTHESIS??? They are: Ho1: Cr 3+and As3+ has no effect on glucose to

Using Spearman's - Is my data statistically significant?

Hi there, I used excel to analyze my data with spearmans rank order co efficient test and came up with the attached table. I have a query about finding out whether my correlation coefficient - 0.420- is statistically significant. This is what i understand (not much!) - take the t value and compare it to the critical val

Statistics Differences using Absolute Values in ANOVA

Optional Extra Credit Project Due June 14 Good for up to 10 points, depending on how thorough and creative your work is. Please make sure to show me everything in order to receive the greatest benefit. Please evaluate the following null hypothesis, and apply the principles of statistical inference as appropriate. T

Hypothesis Testing/Regression Analysis/ANOVA Testing

Please see attached. There are a total of 5 problems. Student is requiring assistance in how these problems are worked.

What you need to know about null hypothesis?

Here is the scenario: Suppose we hypothesize that there is a negative (inverse) relationship between treatment and depression. We'd like to test this hypothesis, so we obtain two samples. Sample 1 is drawn from a population of depressed persons who have not received any type of treatment. Sample 2 is drawn from a population o

What is the null hypothesis of that which Equation #2 tests? Equation #2: Z= (P1- P2) / square root of (p1q1/n1+p2q2/n2)

Equation #2: Z= (P1- P2) / square root of (p1q1/n1+p2q2/n2) What is the null hypothesis of that which Equation #2 tests? (In this case, please DO NOT use symbols in your answer. Just write out, in words, the null hypothesis.) See attached document

Statistics question

A researcher hypothesizes that the lowering in cholesterol associated with weight loss is really due to exercise. To test this, the researcher carefully controls for exercise while comparing the cholesterol levels of a group of subjects who lose weight dieting with a control group that does not diet. The difference in mean chole

Hypothesis Testing: Average Speed

Question: Suppose a candidate running for sheriff claims that she will reduce the average speed of emergency response to less than 30 minutes. (30 minutes is thought to be the average response time with the current sheriff.) There are no past records, so the actual standard deviation of such response times cannot be determined.

A) Calculate the mean and variance of the credit card balances for the male customers and the mean and variance of the credit card balances for the female customers. b) Based on just these two calculations, would you guess that there is a significant difference between the two means? Between the two variances? c) What conclusion should the Capital Bank reach about the mean balances for male and female customers? State the appropriate null and alternative hypotheses, and test at a significance level of alpha = .05 whether they have the same means of their credit card balances. d) Is there reason to believe that the two groups differ with respect to variability of account balance? State the appropriate null and alternative hypotheses, and test at a significance level of alpha =.02 whether they have the same the variances of their credit card balances.

The Capital Bank Marketing Department has recently conducted a study of a sample of the bank's customers. At issue is whether there is a difference between the mean credit card balance between female and male customers. If they find that the two groups differ, they will target the lower group with a marketing campaign designed t

Correlation Coefficient: Weight Data

Please show the process to work the following problems.

Stats

A real estate agent wishes to see if there is a difference in appraisal values given to homes by real estate appraisers and by tax assessors. Real Estate Appraisers Tax Assessors Means \$83,256 \$88,354 S \$ 3,142 \$ 2,341 N 15 15 Find the test value. ONLY!!! In testing for a dif

Hypothesis Testing - decision making situations

Consider some decision-making situations in Business Management field of study, and describe two or more in which tests of one or more population variances are important. Use Internet resources to provide examples of situations in which population variance tests were performed. Be sure to include the url address where you found

Hypothesis Testing for Samples

You are the manager of a factory that produces Mini-Oats Cereal. The factory has an automated packaging machine that can be set at any targeted fill level between 12 and 32 ounces. Every box of cereal is not expected to contain exactly the targeted weight, but the average of all boxes filled should. At the end of every shift (8

For OTA 103997 only

Only for above listed OTA. Find the margin of error E: Grade point averages, 99% confidence, n= 75, mean = 2.76, s= 0.88

Critical Value and Decision

In an experiment to determine the effect of nutrition on the attention spans of elementary school students, a group of 15 students were randomly assignment to each of three meal plans: no breakfast, light breakfast, and full breakfast. Their attentions spans (in minutes) were recorded during a morning reading period and are sho

Testing

He U.S. Bureau of Prisons publishes data in Statistics Report on the times served by prisoners released from federal institutions for the first time. Independent random samples of released prisoners in the fraud and firearms offense categories yielded the following information on time served in months. Mean s n Samp

Mental Health Classification

1. A study was conducted that examined the relationship between mentah-health classification and thoughts of suicide. The mental health of each person in a sampl of 295 was classified as normal, mild psychiatric illness or severe psychiatric illness. Also, each person was asked: "Have you recently found that the idea of t

Significance Level and Improvement in Tread Design

Please see the attached file for full problem description. --- A company that produces bias-ply tires is considering a certain modification in the tread design. An economic feasibility study indicates that the modification can be justified only if true average tire life under standard test conditions exceeds 20,000 miles. A

Hypothesis Testing of Normally Distributed Samples

An astronomer is testing the claim that the mean brightness of a certain star is now more than 30 units. She is able to get 6 readings on the star during her experiment as shown in the table. Using &#945; = 0.01, does this indicate a new mean brightness of more than 30? DATA Reading Brightness 1 29 2 29 3 29 4 3

3693-stats

Category: Mathematics > Probability Problems Subject: Test of Statistical Hypothesis Details: To whom it may concern, I need help answering these 4 problems. Please include, 1) all the steps with details on how to arrive at each solution. 2) final solution I prefer to have everything worked out in MS Word and MS Ex

Does the questionnaire seem to be effective in identifying compulsive buyers?

Use traditional method of testing hypothesis. Researchers designed a questionnaire to identify compulsive buyers. For a sample of consumers who identified themselves as compulsive buyers, scores have a mean of 0.83 and a standard deviation of 0.24. Assume the subjects were randomly selected and that the sample size was 32. U