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Hypothesis Testing

One Sample Tests of Hypothesis: Prop bets at Mirage for Super Bowl Sunday

According to news reports, Las Vegas betting parlors increased the number of proposition (prop) bets available to gamblers for this year's Super Bowl (Example: Which team will be the first to suspend a starting player for a team rules violation?). It is believed that the mean number of prop bets per typical gambler is normally

Waiting line model - Queuing Theory

Question 1 Produce trucks arrive at the weigh station at the California border at a rate of 3 per hour according to a Poisson distribution. Livestock trucks arrive at that same weigh station at a rate of 2 per hour according to a Poisson distribution. What is the probability that the number of livestock trucks arriving at the

Hypothesis Testing of Population Proportion: Traditional Method

By using the Traditional Method and Z test value, find the following: The researcher estimated that out of the 100 students at least 50% of the students would be exposed to movies and TV w/ crude humor at least 2-4 times per week. With a sample of 50 students the researcher found that 57% of the students were exposed to crude

Compute T-Value Obtained from Table

Exhibit 13-3 Below you are given a partial Excel output based on a sample of 25 observations. Coefficients Standard Error Intercept 145.321 48.682 x1 25.625 9.150 x2 â?'5.720 3.575 x3 0.823 0.183 Refer to Exhibit 13-3. The t value obtained from the table to test an in

More variation in the processing time of the new machine

A computer manufacturer is about to unveil a new, faster personal computer. The new machine clearly is faster, but initial tests indicate there is more variation in the processing time. The processing time depends on the particular program being run, the amount of input data, and the amount of output. A sample of 16 computer run

Hypothesis Testing & Variance: AIU job satisfactions data

See data file attached. Using AIU's survey responses from the AIU data set,complete the following requirements in the form of a report: 1. Perform a two-tailed hypothesis test on both the intrinsic and the extrinsic variable's data, using a .05 significance level. 2. Begin by creating a null and an alternate statement

Hypothesis Testing of Mean:IQ scores of Statistics Professor

Null and Alternative hypothesis. For the following claim, find the null and alternative hypotheses, test statistic, P-value, critical value, and draw a conclusion. Assume that a simple random sample has been selected from a normally distributed population. Answer parts a-e. Claim: The mean IQ score of statistics professors

Test the Claim of Average Minutes to Complete a 1 Mile Run

Studies have shown that humans complete a 1 mile run in an average of 12.2 minutes. There is a separate group of 30 who complete a 1 mile run with an average of 8.67 minutes with a standard deviation of 0.33 minutes. a- Using a 0.05 significance level, test the claim that the population mean is different than 12.2 minutes bas

Hypothesis Testing of Population Proportion Significance

Joseph has a career batting average of 0.314%. In 2000 he had 179 hits of 663 at-bats. At the 5% significant level, test the claim that there is a significant difference between 2000 batting percent and his career batting percent of 0.314.

Hypothesis Testing: Independent Sample t Test..

See the attached file for the data. Insurance adjusters are concerned about the high estimates they are receiving from Jocko's Garage. To see if the estimates are unreasonably high, each of 10 damaged cars was taken to Jocko's and to another garage and the estimates recorded. Here are the results: Test the null hypothesi

Conducting a hypothesis test for a population mean

Please help with the following problem. You have a sample size of 120 and the population standard deviation of 20. You are testing the null hypothesis of whether the population mean is 120 or not. A. What are the critical values for rejection when Type I error is 5%? B. If actual mean is 121, find the Type II error C.

Pew Research Automobiles Driving

8.14 Do you enjoy driving your car? The Pew Research Center recently polled n = 1048 U. S. drivers and found that 69% enjoyed driving their automobiles. (a) Construct a 95% confidence interval for the proportion of U. S. drivers who enjoy driving their automobiles. (b) In 1991, a Gallup Poll reported this percent to be 79%


1. Different neighbourhoods may have different crime statistics. A sample of 10 days in Neighbourhood A revealed the following number of crimes per day: 15 12 16 17 15 14 16 10 12 14 A sample of 12 days in Neighbourhood B revealed the following number of crimes per day: 17 13 15 18 16 19 11 21 22 13 16 18 At a 5% l

Testing blood lipid levels

More on blood lipid levels. LDL is also known as ' bad' cholesterol. Suppose the researchers wanted to test the hypothesis that LDL levels are higher in sedentary males than in sedentary females. Describe appropriate null and alternative hypotheses and carry out the significance test using a = 0.05. Report the test statistic wit

Sample of NHTSA Conducted Crash Tests of Child Booster Seats

The NHTSA conducted crash tests of child booster seats for cars. Listed below are results from those tests, with the measurements given in hic (standard head injury condition units). The safety requirement is that the hic measurement should be less than 1000 hic. Use a 0.01 significance level to test the claim that the sample is

Statistics: Does ad placement matter?

Does ad placement matter? Corporate advertising tries to enhance the image of the corporation. A study compared two ads from two sources, the Wall Street Journal and the National Enquirer. Subjects were asked to pretend that their company was considering a major investment in Performax, the fictitious sportswear firm in the ads.

Statistics: Analysis of food intake and weight gain

Food intake and weight gain. If we increase our food intake, we generally gain weight. Nutrition scientists can calculate the amount of weight gain that would be associated with a given increase in calories. In one study, 16 nonobese adults, aged 25 to 36 years, were fed 1000 calories per day in excess of the calories needed to

Average annual income of dentists in 2005 was $110,000.

The Bureau of Labor Statistics reported that the average annual income of dentists in the year 2005 was $110,000. A sample of 81 dentists, which was taken in 2006, showed an average annual income of $115,000. Assume the standard deviation of the population of dentists in 2006 is $36,000. a). Suppose you want to test whether t

Calculating Mean and Standard Deviation: New Jobs Example

The Department of Economic and Community Development (DECD) reported that in 2008 that average number of new jobs created per county was 450. The department also provided that following information regarding a sample of five counties in 2009. Bradley 410 Rhea 450 Marion 407 Grundy 428 Sequatchie

Statistics: Tessler Electric utility, sample of telephone response time

Tessler Electric utility requires service operators to answer the telephone calls from customers in an average time of 0.1 minute or less. A sample of 30 actual operator times are drawn, and the results are given in the following table. In addition, operators are expected to determine customer needs and either respond to them

7-11 Find the critical values

See attached file for full problem. 7-11. Do one of the following, as appropriate. (a) find the critical value (b) find the critical value (c) State that neither the normal nor the t distribution applies. Confidence level 90%; n = 16; o is known; population appears to be very skewed. Find the critical values: a.

Minimum sample size given margin of error

7-8. Use the given margin of error, confidence level, and population standard deviation (o) to find the minimum sample size required to estimate an unknown population means (u) Margin of error: 0.5 inches, confidence level: 90%, o=2.7 inches A confidence level of 90% requires a minimum sample size of ______

Professor Pink Panther's test; Dr. Sehr Kurz's summary data

Quiz #4 Professor Pink Panther is a referee (reviewer) for a prestigious international journal, Manuscripta Absurda. Recently, he is giving two articles to review. The following information is for Questions 1 through 5. There are two personality types, Type-A and Type-B. Married couples are made up of three

Estimate weight of M&Ms

A data set of red and orange M&M's yield the following sample weight data. Use the 0.05 significance level to test for equality of the two population means using the traditional approach to hypothesis testing. Red M&M's n1 = 21 x1 = 0.9097 grams s1 = 0.0275 grams Orange M&M's n2 = 8 x2 = 0.9251 grams s1 = 0.0472 g

Test driving habits of women age 16-24

The insurance company is reviewing the driving habits of women aged 16-24 to determine if they should continue to pay higher premiums than women in a higher age bracket. In a study of 750 rendomly selected women drivers aged 16-24, the mean driving distance for one year is 6900 miles. The population standard deviation is 2944

Statistics: Clinical Trial for New Compound

A clinical trial was conducted comparing a new compound designed to improve wound healing in trauma patients to a placebo. After treatment for 5 days, 58% of the patients taking the new compound had a substantial reduction in the size of their wound as compared to 44% in the placebo group. The trial failed to show significance.

Statistical Problems for Standard Deviation Distribution

Problem 2b: For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3. Problem 6: For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general

Computing the Mean, Standard Deviation, and Testing Hypothesis

Show all work. A group of young businesswomen wish to open a high fashion boutique in a vacant store, but only if the average income of households in the area is at least $25,000. A random sample of 9 households showed the following results: $28,000 $23,000 $24,000 $24,000 $27,000 $26,000 $26,000 $25,000 $22