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# Hypothesis Testing

### Coincidence and Probability

The Spanish patients, two men and two women, were elderly and very ill. All four had undergone routine dialysis at the Hospital de la Princesa. Soon after, they began sweating and vomiting, some of them in excruciating pain. They died within a few hours of receiving treatment. Nothing seemed exceptional about the deaths of t

### User error

Although this critique was later discarded, how does user error affect the marketplace. When I buy my morning coffee at Starbucks, the cup warns me: "Careful, the beverage you are about to enjoy is extremely hot." The tag attached to a windshield cover I purchased last winter cautioned me not to use it while driving. Where sh

### Quantifiable Statistics

The thing about selling all of those drugs, devices, and solutions is that a lot can go wrong. Nearly every product that Baxter delivers is a matter of life and death. But when the outcome is death, it can be incredibly difficult to determine a treatment's effectiveness. Was the death normal and predictable? Or did the treatment

### Proportion testing using Z test

Workers Bosses N1=436 N2=121 X1=192 X2=40 Assume that you plan to use a significance level of a=.05 to test the claim that P1 = P2. Use the given sample sizes in numbers of success to find p -value.

### Population - A population consists of the following five values: 2, 2, 4, 4, and 8.

A population consists of the following five values: 2, 2, 4, 4, and 8. a. List all samples of size 2, and compute the mean of each sample. b. Compute the mean of the distribution of sample means and the population mean. Compare the two values. c. Compare the dispersion in the population with that of the sample means.

### Hypothesis testing for mean

A sample of 93 IQ scores was randomly selected from a certain population. At the 0.03 level of significance, test the hypothesis that the population has a mean IQ of 105. Assume that the population standard deviation is 11.9 and that the sample mean was 107 for the 93 scores.

### Statistics - Population Variances Questions

1. When testing for the difference between 2 population variances with sample sizes of N1 = 8 and N2 = 10, the number of degrees of freedom are a. 8 and 10 b. 7 and 9 c. 18 d. 16 [See the attached questions file.]

### Determine if there is a Significant Linear Relationship

Assume that a sample of n pairs of data results in the given value of r. For alpha equal .05, determine if there is a significant linear relationship between x and y. Let n = 22, r = -0.087.(Yes or No).

### Stating Case Study Null and Alternative Hypothesis

1. A decade-old study found that the proportion of high school seniors who felt that "getting rich" was an important personal goal was 73% . Suppose that we have reason to believe that this proportion has changed, and we wish to carry out a hypothesis test to see if our belief can be supported. State the null hypothesis Ho and t

### Hypothesis Testing - A presidential candidate's aide estimates that, among all collge students, the proportion p who intend to vote in the upcoming election is at most 65%. If 190 out of a random sample of 260 collge students expressed an intent to vote, can the aide's estimate be rejected at the 0.05 level of significance? ...

A presidential candidate's aide estimates that, among all collge students, the proportion p who intend to vote in the upcoming election is at most 65%. If 190 out of a random sample of 260 collge students expressed an intent to vote, can the aide's estimate be rejected at the 0.05 level of significance? Perform a one-tailed

### Null Hypothesis - A coin-operated drink machine was designed to discharge a mean of 8 ounces of coffee per cup. Suppose that we want to carry out a hypothesis test to see if the true mean discharge differs from 8. State the null hypothesis H0 and the alternative hypothesis H1 that we would use for this test.

A coin-operated drink machine was designed to discharge a mean of 8 ounces of coffee per cup. Suppose that we want to carry out a hypothesis test to see if the true mean discharge differs from 8. State the null hypothesis H0 and the alternative hypothesis H1 that we would use for this test.

### Hypothesis Testing - A coin-operated drink machine was designed to discharge a mean of 8 ounces of coffee per cup. Suppose that we want to carry out a hypothesis test to see if the true mean discharge differs from 8. State the null hypothesis and the alternative hypothesis that we would use for this test. ...

A coin-operated drink machine was designed to discharge a mean of 8 ounces of coffee per cup. Suppose that we want to carry out a hypothesis test to see if the true mean discharge differs from 8. State the null hypothesis and the alternative hypothesis that we would use for this test. Ho: ________________________ H1: ___

### SSE's, SST's, F-ratio, ANOVA, and null hypothesis

Problem 1 An aircraft manufacturer is attempting to determine if the average leg length of the adult male has changed from 44". A sample of 81 men was selected randomly and the average length was found to be 45.5", with a standard deviation of 5.5". Test the null hypothesis that the average leg length of the adult male is 44"

### Hypothesis Testing on Physical Characteristics

A researcher is investigating the physical characteristics that influence whether a person's face is judge as beautiful. The researcher selects a photograph of a woman and modification of the photo by (1) moving the eyes slightly farther apart and (2) moving the eyes slightly closer together. The original photograph and the two

### Hypothesis Testing - With regard to hypothesis testing about two means, what is the distinction between two independent populations and two related populations? Be specific but brief in about 4 or 5 paragraphs, if possible.

With regard to hypothesis testing about two means, what is the distinction between two independent populations and two related populations? Be specific but brief in about 4 or 5 paragraphs, if possible.

### Hypothesis Testing - 1. How can we tell the direction (left tail, two-tailed, and right tailed test) of a hypothesis test? 2. When would we choose a two tailed test by looking at a pair of hypothesis? ... [See the attached questions file.]

1. How can we tell the direction (left tail, two-tailed, and right tailed test) of a hypothesis test? 2. When would we choose a two tailed test by looking at a pair of hypothesis? 3. How can we tell which direction (or no direction) to make the hypothesis by looking at the problem statement (research question)? 4. How

### Hypothesis test with F- value

A sample of 25 concession stand purchases at the October 22 matinee of Bride of Chucky showed a mean purchase of \$5.29 with a standard deviation of \$3.02. For the October 26 evening showing of the same movie, for a sample of 25 purchases the mean was \$5.12 with a standard deviation of \$2.14. The means appear to be very close, bu

### Statistics and Hypothesis Testing: Professor Hardtack's Students

To test the hypothesis that students who finish an exam first get better grades, Professor Hardtack kept track of the order in which papers were handed in. The first 25 papers showed a mean score of 77.1 with a standard deviation of 19.6, while the last 24 papers handed in showed a mean score of 69.3 with a standard deviation of

### In Dallas, some fire trucks were painted yellow (instead of red) to heighten their visibility.

In Dallas, some fire trucks were painted yellow (instead of red) to heighten their visibility. During a test period, the fleet of red fire trucks made 153,348 runs and had 20 accidents, while the fleet of yellow fire trucks made 135,035 runs and had 4 accidents. At &#945; = .01, did the yellow fire trucks have a significantly lo

### Statistics - Hypothesis Testing Non-Sales Items

To measure the effect of a storewide sales campaign on non-sale items, the research director took a random sample of 13 pairs of stores that were matched according to average weekly sales volume. One store of each pair (the experimental group) was exposed to the sales campaign, and the other member of the pair (the control) gro

Part I:  In this exericse, we have a box of paint cans for a project kit.  The box contains 100 bottles in total, with the following colors:   yellow,  black,  green,  blue.   We will randomly select 15 bottles from the box and count how many are yellow.

### Statistical questions: Chi-square, two-tailed hypothesis, optimum sample size

1. Since we have determined the optimal sample size, n, using a three variable formula. Fill in the following table listing the three variables and specify the effect on n (either + or -) of increasing and decreasing each variable, one at a time. VARIABLE EFFECT of INCREASE EFFECT of DECREASE 2. Given a Chi-Squar

### F-Distributed Test Statistics and Linear Regression

Please see the attached document for properly formatted questions.

### Rejection Region For A Hypothesis Test

The owner of a local night club has recently surveyed a random sample of n=250 customers of the club. She would now like to determine whether or not the mean age of her customers is over 30. If so, she plans to alter the entertainment to appeal to an older crowd. If not, no entertainment changes will be made. If she wants to be

### Hypothesis Testing on Grandparent Roles

Please see the attached file for full question. Two independent (unrelated) sample groups of parents and grandparents were recruited. A total of 105 young adult parents, between the ages of 21 and 40 years, participated in this study. A total of 105 middle-aged and older grandparents, ranging in age from 36 to 84 years (M = 6

### Hypothesis Testing

Microsoft Excel was used on a set of data involving the number of parasites found on 46 Monarch butterflies captured in Pismo Beach State Park. A biologist wants to know if the mean number of parasites per butterfly is over 20. She will make her decision using a test with a level of significance of 0.10. The following informat

### Hypothesis test interpretation.

An entrepreneur is considering the purchase of a coin-operated laundry. The present owner claims that over the past 5 years, the average daily revenue was \$675 with a standard deviation of \$75. A sample of 30 days reveals a daily average revenue of \$625. If you were to test the null hypothesis that the daily average revenue w

### Population Variances and Observations

The following hypotheses are given. Please see the attached file. A random sample of five observations from the first population resulted in a standard deviation of 12. A random sample of seven observations from the second population showed a standard deviation of 7. At the .01 significance level, is there more variation i

### Hypothesis testing

Please see attached Chapter 9, exercise number 12 12. The American Sugar Producers Association wants to estimate the mean yearly sugar consumption. A sample of 16 people reveals the mean yearly consumption to be 60 pounds with a standard deviation of 20 pounds. a. What is the value of the population mean? 20 What is the

### Value of the Test Statistic

In recent year, of the 109,857 arrest fro federal offenses, 29.1% were for drug offenses. Use a .01 significance level to test the claim that the drug offense rate is equal to 30%. What is the value of the test statistic?