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# Hypothesis Testing

### Statistical Analysis: Running Red Lights

A random digit dialing telephone survey of 880 drivers asked, "Recalling the last ten traffic lights you drove through, how many of them were red when you entered the intersectinos?" Of the 880 respondents, 171 admitted that at least one light had been red. a)Give a 95% confidence interval for the proportion of all drivers who

### Fatal Accidents Statistical Analysis

As part of a study on transportation safety, the U.S. Department of Transportation collected data on the number of fatal accidents per 1000 licenses and the percentage of licensed drivers under the age of 21 in a sample of 42 cities. Data collected over a one-year period follow. Please see the attached file for the table.

### Test for Differences: Types of Browsers

In a study conducted to investigate browsing activity by shoppers, each shopper was initially classified as a nonbrowser, light browser, or heavy browser. For each shopper, the study obtained a measure to determine how comfortable the shopper was in a store. Higher scores indicate greater comfort. Suppose the following date we

### Hypothesis Testing: Positive or Negative Relationships

1. A researcher demonstrated a correlation of r = 0.60 between teacher attire and student academic performance across 150 grade schools in her state. She concluded that encouraging teachers to be properly attired will increase academic performance. Do you agree or disagree with her conclusion? Why? 2. Give three real life or

### Hypothesis Testing - In a two population test, when will you use independent samples? Provide an example and state the Null and the Alternative hypothesis for the examples in symbolic form.

In a two population test, when will you use independent samples? Provide an example and state the Null and the Alternative hypothesis for the examples in symbolic form.

### Employee Drug Testing: Hypothesis Testing

In 1990, 5.8% of job applicants who were tested for drugs failed the test. At the 0.01 level, test the claim that the failure rate is now lower if a random sample of 1,520 current job applicants results in 58 failures. Does the result suggest that fewer job applicants now use drugs? Give the z score to 2 decimal places to, p(hat

### Snow Tire Skid Properties: Hypothesis Testing

The skid properties of a snow tire have been tested and a mean skid distance of 154 feet has been established for standardized conditions. A new, more expensive tire is developed, but tests on a sample of 17 new tires yield a mean skid distance of 148 feet with a standard deviation of 12 feet. Because of the cost involved, the n

### Hypothesis Testing

Assume that a hypothesis test of the given claim will be conducted. The college Dean of Admissions claims that the times students require to earn a bachelors degree have a mean less than five years. Which equality/inequality (e.g., =, =<, etc.) would use in the Alternative Hypothesis?

### Hypothesis Testing

Assume that a hypothesis test of the given claim will be conducted. The college Dean of Admissions claims that the times students require to earn a bachelors degree have a mean less than five years. Which equality/inequality (e.g., =, =<, etc.) would use in the Null Hypothesis?

### Hypothesis testing : Proportion

It has been reported that 80% of taxpayers who are audited by the IRS end up paying more money in taxes. Assume that the auditors are randomly assigned cases and that one of the ways the IRS oversees its auditors is to monitor the percentage of cases that result in the tax payer paying more in taxes. A sample of 400 cases handl

### Statistical IQ Testing of Employees

Please explain the answers. Descriptions are in the file. 3. In order to test whether the mean IQ of employees in an organization is greater than 100, a sample of 35 employees is taken and the sample value of the computed test statistic, t_ = 3:5 The null and alternative hypotheses are: A) H0: X = 100; Ha: X 6= 100. B) H0:

### Test Findings: sample of difference in wages based on gender

The wages data set has a sample size of 100 people that were surveyed. Our error margin was .05. For the 47 females surveyed the mean wage was \$24,451 per year with a standard deviation of \$12,455 per year. For the 53 males surveyed the mean wage was \$36,492 per year with a standard deviation of \$18,447 per year. Check the clai

### Statistics - Hypothesis Testing Adjustment

Discuss the link between the estimate and the parameter in the context of an hypothesis test. Be sure to reference the appropriate steps of the five step process in your response, based on the steps below: Step 1: State null and alternate hypothesis. Step 2: Select a level of significance Step 3: Identify the test statisti

### Testing of hypothesis problems

Dear OTA, Can you please help me with this homework assignment? Thanks 1. Burney Watt, chief electrician for the Prescott Electrical Coop has been watching the electric bills for 10 properties in Prescottvilla, the up and coming snobby subdivision south of town. The residents there have been complaining that their "b

### 1. The General Social Survey is an annual survey given to about 1,500 U.S. adults selected at random. 2. The university data center has two main computers. The center wants to examine whether computer 1 is receiving ... [See the attached questions file.]

1. The General Social Survey is an annual survey given to about 1,500 U.S. adults selected at random. Each year, the survey contains several questions meant to probe respondents' views of employment. A recent survey contained the question "How important to your life is having a fulfilling job?" Of the 261 college graduates surve

### Important information about Statistics - Hypothesis Testing

Sixty-four students in an introductory college economics class were asked how many credits they had earned in college, and how certain they were about their choice of major. Research question: At &#945; = .01, is the degree of certainty independent of credits earned? ... [See the attached question file.]

### Regression Analysis of Wine Consumption

Please see the attached file. **All work shown (step by step), in simple terms please!!! No excel, just formulas**. 20) A marketing research firm wished to study the relationship between wine consumption and whether a person likes to watch professional tennis on television. One hundred randomly selected people are as

### Significance level and p-value

A large department store hired a researcher to compare the average purchase amounts for the downtown store with that of its mall store.  The information shown was obtained.  At the 0.01 significance level can it be concluded that the mean amount spent at the mall store is larger?Estimate the p-value? Average purchase amount

### Hypothesis Testing - The production line that packages boxes of raisins at a snack food manufacturer will be considered operating properly if the average weight of the boxes of raisin is 3.5 ounces with a standard deviation of 0.3 ounces. A random sample of 20 boxes showed an average weight of 3.30 ounces. ...

The production line that packages boxes of raisins at a snack food manufacturer will be considered operating properly if the average weight of the boxes of raisin is 3.5 ounces with a standard deviation of 0.3 ounces. A random sample of 20 boxes showed an average weight of 3.30 ounces. a. State the value of the correct reje

### Hypothesis Testing using ANOVA

Scrap rates per thousand (parts whose defects cannot be reworked) are compared for 5 randomly selected days at three plants. Does the data prove a significant difference in mean scrap rates? ScrapRate Plant A Plant B Plant C 11.4 11.1 10.2 12.5 14.1 9.5 10.1 16.8 9.0 13.8 13.2 13.3 13.7 14.6 5.9.

### P-value equality of mean

Do a two-sample test for equality of means assuming equal variances. Calculate the p-value. a. Comparison of GPA for randomly chosen college juniors and seniors: ¯x1 = 3.05, s1 = .20, n1 = 15, ¯x2 = 3.25, s2 = .30, n2 = 15, &#945; = .025, left-tailed test. b. Comparison of average commute miles for randomly chosen stude

### Chi-Statistic in Hypothesis Testing

A machine used for packaging seedless golden raisins is set so that their standard deviation in the weight of raisins packaged per box is 0.25 ounce. The operations manager wishes to test the machine setting and selects a sample of 30 consecutive raisin packages filled during the production process. Their weights are as record

### Hypothesis Testing

Following sample data shows the quarterly earnings in millions for two US companies. Your research interest is (at .05 level of significance) determining if the average earnings for these companies are different. Justify your answer by doing a five step testing of hypothesis. Also, compute the p-value of the test. Company -

### Pepsi and Health Hypothesis Testing

In a recent survey, 10 percent of the participants rated Pepsi as being "concerned with my health." PepsiCo's response included a new "Smart Spot" symbol on its products that meet certain nutrition criteria, to help consumers who seek more healthful eating options. At &#945; = .05, would a follow-up survey showing that 18 of 10

### Statistics in business - High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound meter. Noise level is defined as "Low" (under 88 decibels), "Medium" (88 to 91 decibels), ... [See the attached question file.]

See attachment for problem High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound meter. Noise level is defined as "Low" (under 88 decibels), "Medium" (88 to 91 decibels), or "High"

See attachment for problem A student team examined parked cars in four different suburban shopping malls. One hundred vehicles were examined in each location. Research question: A

### Do average calls per week differ from district to district?

1. Using the data file TRX.XLS (attached), construct a 95% confidence interval for the average number of prescriptions written for Prilosec. Assume the distribution in normally distributed. There are 24 months to be averaged. Use Descriptive Statistics in Excel and be sure to check the appropriate options. If you can't see the o

### Hypothesis Testing

A lumber company has claimed that the standard deviation for the lengths of their 6 foot boards is 0.5 inches or less. To test their claim , a random sample of 17 six-foot boards is selected; and it is determined that the standard deviation of the sample is 0.42. Do the results of the sample support the company's claim? Use alph

### Description of Statistics - Hypothesis Testing

1. Consider the following hypothesis test: Ho: u</= 12 Ha: u>12 A sample of 25 provided a sample mean x=14 and a sample standard deviation s = 4.32 a. Compute the test statistic. b. Use the t distribution table to compute a range for the p value c. At alpha= 0.05, what is the conclusion. d. What is the rejection rule us

### Hypothesis Testing - 22. Car manufacturers have to publish an estimated MPG for each model production. Prior to manufacturing "Car A" the manufacturer stated that the MPG. ... [Please see the attached questions file.]

22. Car manufacturers have to publish an estimated MPG for each model production. Prior to manufacturing "Car A" the manufacturer stated that the MPG. ... 25. A group of University of Florida psychologist investigated the effects of age and gender on the short-term memory of adults ... 26. The Time/CNN survey, 24% if 205 s