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# Hypothesis Testing

### Interpreting the Null hypothesis significance test (NHST), including the t statistics, degrees of freedom, sample size, effect size and p value in social science studies.

A researcher compares men's and women's attitudes toward "road rage." Specifically, college students are asked to read a brief scenario describing a road rage incident in which a driver of a car attempts to scare a bicycle rider who accidentally cut across his path. The driver aims his car at the bicyclist and the bicycle rider,

### Statistics

Chapter 9, Section 2 Problem 12 Interpreting Displays - Conduct the hypothesis test by using the results from the given displays. Bednets to Reduce Malaria - In a randomized controlled trial in Kenya, insecticide-treated bednets were tested as a way to reduce malaira. Among 343 infants using bednets, 15 developed malaria

### Statistics Problem

See data file attached. Metropolitan Research, Inc., a consumer research organization, conducts surveys designed to evaluate a wide variety of products and services available to consumers. In one particular study, Metropolitan looked at consumer satisfaction with the performance of automobiles produced by a major Detroit manu

### Article Review: Movies and the Mystery of the Missing Trade

Prepare an analysis of your selected article. Start by identifying and summarizing the hypothesis described in the article. Then explain whether the hypothesis was rejected or accepted, and what the implications of this finding are for the study. Be sure to properly cite your article. https://www.aeaweb.org/annual_mtg_papers/

### Hypothesis testing: z test for soda filled bottles; z test for new medical claims system

See attached two files. In first file there are 2 questions. MOST IMPORTANT is these problems need be done using the second utility file. The following data represent the actual amount of soda in a sample of fifty 2-liter bottles. You are in charge of production and must assure that the bottles don't have too much or too

### Statistics: What is null hypothesis; tests, p value, conclusion

Independent simple random samples from two groups of patients used in an clinical trial yielded the following measurements on glucose levels following a new drug treatment: Group A: 54, 99, 105, 46, 70, 87, 55, 58, 139, 91, 102, 110 Group B: 93, 91, 93, 150, 80, 104, 128, 83, 88, 95,94, 97 Do these data provide sufficien

### Statistics: T distribution, one and two tailed test, variance

4. Explain why t distribution tend to be flatter and more spread out than the normal distribution. 12. Last fall a sample of n = 36 freshman was selected to participate in a new four hour training program designed to improve study skills. To evaluate the effectiveness of the new program, the sample was compared with the

### Statistics Ch 8-2, problems 22, 28, 46; Ch 8-3, P6, 18, 28; Ch 8-4, P12, 20

Chapter 8, Section 2 Problem 22 Finding critical values - Assume that the normal distribution applies and find the critical z values. x = 0.01; H1 is p > 0.5 Problem 28 Finding Test Statistics - Find the value of the test statistic z using Seat Belts - The claim is that more than 75% of adults always wear

### 6 Statistics Problems: Value of the t statistic; reject or fair to reject the null hypothesis

1. A researcher recorded the amount of time each bird spent in the plain chamber during a 60-minute session. Suppose the study produced a mean of M=37 minutes on the plain chamber with SS=288 for a sample of n=9 birds. (Note: If the eye spots have no effect, then the birds should spend an average of µ=30 minutes in each chamber

### When a Simulation is Better than Hypothesis Testing

a) Can you think of an example related to your work where a simulation could not be performed, (b) one where a simulation could be performed, yet a formal test would be preferred? (c) What specific (different than hiring) business decisions would a manager make using hypothesis testing?

### General Statistics Problems: hypothesis tests, comparing proportions, sample sizes, analyzing results of surveys

See attached file for full details of problems. ----- 9.69 Late payments of medical claims can add to the cost of health care. An article reported that for one insurance company, 85.1% of the claims were paid in full when first submitted. Suppose that the insurance company developed a new payment system in an

### Method of selection for faculty; evaluate new teaching tool

From the school of Allied Health, 10 faculty out of 40 are to be selected to attend a summer conference. Of the 40, 25 are women and 15 are men. Select the 10 by the most appropriate method. A new teaching tool developed by the Allied Health department is claimed to help 68% of students learn at a faster pace. State the

### Test of Hypothesis: Type of error, Alpha, Mu vs u

I am wondering if mu is the same thing as u. I have two questions on a worksheet due (I have the others answered already) and I'm not finding mu in my book. 1. If Ho: u=30 and Ha: mu>30 and x=34.7 what type of error is made if real values mu=32 and x =33? 2. If Ho: u=50 and Ha: mu. 59 and sigma = 10 what is alpha if x excee

### Sample t test: Report hypothetical results

Think about a real world situation or problem that could be addressed using a single-sample t test. For this situation or problem, clearly identify the independent and dependent variables you would study; generate the statistical null and alternative hypotheses; describe what information the effect size would tell you that the

### Statistics: Two tailed test

Other research examining the effects of preschool childcare has found that children who spent time in day care, especially high quality daycare, perform better on math and language tests than children who stay at home with their mothers (Broberg, Wessels, Lamb, & Hwang, 1997). Typical results, for example, show that a sample of

### Test hypothesis for relationship between age group and communication preferred

USA Today reported on preferred types of office communication by different age groups. Suppose the results were based on a survey of 500 respondents in each age group. The results are cross-classified in the following table: Type of Communication Preferred AGE GROUP Group Face to Emails Others Total

### Statistics: Test if cocaine use by pregnant women produces low birth weight babies

Please show detailed solutions. Does cocaine use by pregnant women cause their babies to have low birth weight? To study this question, birth weights of babies of women who tested positive for cocaine/crack during a drug-screening test were compared with the birth weights for babies whose mothers either tested negative or we

### Signifigance level

Number 8 A coffee manufacturer is interested in whether the mean daily consumption of regular-coffee drinkers is less than that of decaffeinated-coffee drinkers. Assume the population standard deviation for those drinking regular coffee is 1.20 cups per day and 1.36 cups per day for those drinking decaffeinated coffee. A rand

### Statistics: Standards high-sulfur coal; New Hampshire Insurance; pay for union nurses

See attached file for format of answers. Number 5 A nationwide sample of influential Republicans and Democrats was asked as a part of a comprehensive survey whether they favored lowering environmental standards so that high-sulfur coal could be burned in coal-fired power plants. The results were: Republicans Democrats

### Summation by parts and Ditichlet's Test

Suppose {a_n} (n=1 to N) and {b_n} (n=1 to N) are two finite sequences of complex numbers. Let B_k = sum b_n (sum n=1 to k) denote the partial sum of the series sum (b_n) with the convention B_0=0. a. prove the summation by parts by formula sum (a_n b_n) (sum goes from n=M to N) = a_N B_N -a_M B_{M-1}- sum( [a_{n+1}-a_n}]B

### Statistics problems: Analysis method, probability, time intervals

The following information is for Questions 2. It is an open secret that airlines overbook flights, but I have just learned recently that bookstores underbook (I might have invented this new term.) textbooks.......... To make a long story short, our UMUC designated virtual bookstore, MBS Direct, routinely, as a matter of bu

### American Insurance Institute: Two- sample tests of hypothesis

The president of the American Insurance Institute wants to compare the yearly costs of auto insurance offered by two leading companies. He selects a sample of 15 families, some with only a single insured driver, others with several teenage drivers, and pays each family a stipend to contact the two companies and ask for a price q

### Sequences & series

File is attached, it's in french but english translation is below: 1.Find a formula general for the general term for the following sequences: Determine if they are convergent or divergent. If the sequence is convergent find its limit. 2.Let: a1=2 â?¦â?¦. a.Reasoning by induction show that 0<an=<2 b.show by induction for

### Validity of test with difference sample sizes

2. A Wall Street Journal article suggests that age bias is becoming an even bigger problem in the corporate world. In 2001, an estimated 78% of executives believed that age bias was a serious problem. In a 2004 study by ExecuNet, 82% of the executives surveyed considered age bias a serious problem. The sample size for the 2004 s

### Statistics

4. For a candidate to win in a congressional district, he has to have won over half of the vote. The Republican candidate takes a poll to assess his chances in a two-candidate race. He polls 1200 potential voters and find that 621 plan to vote for the Republican candidate. Does the Republican candidate have a chance to win? Use

### Test Airport baggage scanning machine claims of 580 bags per hour

The manufacturer of an airport baggage scanning machine claims it can handle an average of 580 bags per hour. At alpha (?) = .01, would a sample of 18 randomly chosen hours with a mean of 525 and a standard deviation of 45 support the manufacturer's claim? Do both by hand and with Excel. Note- Use a 0.05 level of significance

### Statistics Problems: Test for mean, proportion, paired samples, independence

See attached file for clarity of the tables included. 1. ONE SAMPLE HYPOTHESIS TEST FOR MEAN: A bowler who has averaged 196 pins in the past year is asked to experiment with a ball made of a new kind of material. If he rolls 25 games with the new ball, averaging 204 pins with a standard deviation of 24.9, can one conclude

### Statistics: Identify the test statistice, critical value, conclusion, p value

1. A coin mint has a specification that a particular coin has a mean weight of 2.5g. A sample of 39 coins was collected. Those coins have a mean weight of 2.49382g and a standard deviation of 0.01581g. Use a 0.05 significance level to test the claim that this sample is from a population with a weight equal to 2.5g. Do the coins

### Significance test is used to prevent machine from under or over filling quart bottles

A significance test is used to prevent a machine from under filling or overfilling quart bottles. On the basis of a sample, the null hypothesis is rejected and the machine is shut down for inspection. A thorough examination reveals that there is nothing wrong with the filling machine. From a statistical standpoint, was there a t

### Statistics: Unit 7 MML Project: Light bulb life, killowatt hour usage, microwave repair

A light bulb manufacturer guarantees that the mean life of a certain type of light bulb is at least 950 hours. A random sample of 35 light bulbs has a mean life of 934 hours with a standard deviation of 80 hours. Do you have enough evidence to reject the manufacturer's claim? use a=0.04. (a) Identify the null hypothesis and a