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Hypothesis Testing

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.

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.]

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 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 - 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

Inference about Population Proportion

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

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

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?

Hypothesis Testing - Heather Carielli is a former student who earned a master degree at the University of Arkansas. When she randomly selected 16 new text books in the college book store she found that they had prices with a mean of $70.41 and a standard deviation of $19.70. Is there sufficient evidence to warrant rejection of a claim in the college catalog that the mean price of the textbook at the college is less than $75.00? use .05 significance level. Accept or the reject the null?

Heather Carielli is a former student who earned a master degree at the University of Arkansas. When she randomly selected 16 new text books in the college book store she found that they had prices with a mean of $70.41 and a standard deviation of $19.70. Is there sufficient evidence to warrant rejection of a claim in the colle

Hypothesis testing - Data set includes the heights of parents

A data set includes the heights of parents of 20 males. If the difference in height for each set of parents is found by subtracting the mother's height from the father's height, the result is a list of 20 values with a mean of 4.4 inches and a standard deviation of 4.2 inches. Use a .01 significance level to test the claim the

Accept or Reject the Null Hypothesis

In a Sgallop poll of 1012 randomly selected adults, 9% said cloning of humans should be allowed. Use a .05 significance level to the test claim that less than 10% of all adults said that cloning should be allowed. Accept or reject the null hypothesis?

Hypothesis Testing: Processing Orders on the Same Day Received

The web-based company Oh Baby! Gifts has a goal of processing 95 percent of its orders on the same day they are received. If 485 out of the next 500 orders are processed on the same day, would this prove that they are exceeding their goal, using a = .025?

Hypothesis Testing: Mean vs. Hypothesized Value

Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard devi

Change in poupularity over time

Surveys have been widely used by politicians around the world as a way of monitoring the opinions of the electorate. Six months ago, a survey was undertaken to determine the degree of support for a national party leader. Of a sample of 1,100, 56% indicated that they would vote for this politician. This month, another survey o

Answers to Hypothesis Testing Questions in Excel

I am having trouble with some stats problems. Can you assist me? Thanks in advance The NPC, Inc. is a large mail order company that ships men's shirts all over the United States and Canada. They ship a large number of packages from their warehouse in Delta, Ohio. Their goal is to have 95 percent of the shipments delivered

Using Excel for Answers to Hypothesis Tests

An operations manager who supervises an assembly line has been experiencing problems with the sequencing of jobs. The problem is that bottlenecks are occurring because of the inconsistency of sequential operations. He decides to conduct an experiment wherein two different methods are used to complete the same task. He measure

Questions for Hypothesis Testing in Excel

Use a 10% significance level. Every month a clothing store conducts an inventory and calculates the losses due to theft. The store would like to reduce these losses and is considering two methods. The first is to hire a security guard, and the second is to install cameras. To help decide which method to choose, they hired a

Inferring about population Means

In random samples of 12 from each of two normal populations, we found the following statistics: Xbar1 = 74 S1= 18 Xbar2 = 71 S2 =16 a) Test with α= .05 to determine whether we can infer that the population means differ. b) Repeat part a increasing the standard deviations to S1= 210 and S2 =198. c) Describe what