Explore BrainMass
Share

Hypothesis Testing

Two-tailed tests and further statistical analysis

A coin-operated drink machine was designed to discharge a mean of 6 ounces of coffee per cup. In a test of the machine, the discharge amounts in 14 randomly chosen cups of coffee from the machine were recorded. The sample mean and sample standard deviation were 6.11ounces and .16ounces, respectively. If we assume that the discha

The solution to Test of hypothesis

Given the following hypothesis: Ho: M = 400 H alternative: M not equal to 400 For a random sample of 12 observations, the sample mean was 407 and the sample standard deviation 6. Using the .01 significance level: a. State the decision rule. b. Compute the value of the test statistic. c. What is your decision reg

The answer to One sample Z test

For this exercise answer the questions: A. is this a one-or two- tailed test? B. what is the decision rule? C. what is the value of the test statistic? D. what is your decision regarding H¥ï? E. what is the type p - value? Interpret it. The following information is available. H 10 HÌ > 10 The sample mean is 12

Probability of Individual Scores

Individual scores of a placement examination are normally distributed with a mean of 84.2 and a standard deviation of 12.8. If the score of an individual is randomly selected, find the probability that the score will be less than 90.0. If a random sample of size n = 20 is selected, find the probability that the sample mean

Hypothesis testing and level of measurement

IDENTIFYING LEVEL OF MEASUREMENT There are four levels of measurement, two are numeric and two are attribute data. This first time around, try to identify if a question produces a number or a text number. This not always an easy as you will see. This will be needed later when choosing a hypothesis test. Please attached, I at

Hypothesis testing

One Sample Hypothesis Testing Paper Using ratio or interval numerical data from one of the data sets available through the "Data Sets" link on your page, develop one research question from which you will formulate a research hypothesis. Prepare a 1,050-1,750-word paper describing the results of a hypothesis test of one popu

Hypothesis

Hypothesis test for the difference of population proportions For several decades, it was a common practice in Southern California for houses to be built with pools in the backyard (as any airplane flight which ends at a Southern California airport will reveal). Now, however, that practice may be changing, possibly because of t

P-Value

The liquid chlorine added to swimming pools to combat algae has a relatively short shelf life before it loses its effectiveness. Records indicate that the mean shelf life of a 5-gallon jug of chlorine is 2,160 hours (90 days). As an experiment, Holdlonger was added to the chlorine to find whether it would increase the shelf life

What is the p value and can you describe the steps in formal hypothesis testing?

I need help with proving that a population mean is not 150. Use an alpha of 5% and set up the full, detailed, five step hypothesis test. Assume when the sample 200 is taken the sample standard deviation is 10 and the sample mean is 151.77. What is the p value? Describe the steps in formal hypothesis testing. Make at least

Samplings of Pine Trees and Spruce Trees

A field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling. Can he conclude, at the .10 level of significance, that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree?

Non-Parametric Test SPSS

In the attached SPSS output, the variables tell whether a husband and wife are employed full time. I've run the sign test to test whether husbands and wives are equally likely to be employed full time. Having trouble formulating a conclusion. Are they equally likely?

Hypothesis testing : Two proportions

46. As a condition of employment, Fashion Industries applicants must pass a drug test. Of the last 220 applicants 14 failed the test. Develop a 99 percent confidence interval for the proportion of applicants that fail the test. Would it be reasonable to conclude that more than 10 percent of the applicants are now failing the tes

Hypothesis test two sample student t test

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 + The last 24 papers showed a mean score of 69.3 with a standard deviation of 24.9.

Discussions - . Tests of hypothesis for two populations

1. Tests of hypothesis for two populations. List one test statistic that could be used for comparing two populations with hypothesis testing. Can you think of an example where this could be used? 2. Contrary to major television media popular belief, the United States does much good for the world. For example, the United State

Stats and Statistics: confidence intervals, p-values, hypothesis testing.

1. After a sample of numbers is taken from a population, the 95% confidence interval is calculated out at {10.5, 12.0} What is the correct way to interpret this confidence interval? Choose one. (1 point) A) 95% of all values in the population are between 10.5 and 12.0 B) The true population mean has to be between 10.5 and

Hypothesis Testing: Compute P-Value

You want to prove that a population mean is not 7. Data is ratio and a large sample size will be used (n = 225). When the sample is done the sample mean is computed to be 7.2 and the sample standard deviation is 1.5. Test the hypothesis using an alpha of 5%. Use formal hypothesis testing and compute the p-value.

SPSS - Parametric testing, Bonferroni multiple comparison

I need help interpreting the attached SPSS output. Consider the variable for respondents' average income (r inc dol) Is the average income for all respondents 31,126.50? Is the average income for people with less than a high school degree 17,366.97? Is the average income for people with graduate degrees 58,128.38? The

Identify a hypothesis from an 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. -----------------------------------------------------------------------------------------------------------------------------

Hypothesis testing: differences in variance

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

Conduct a hypothesis test for lovastatin

Does lovastatin (a cholesterol-lowering drug) reduce the risk of heart attack? In a Texas study, researchers gave lovastatin to 2,325 people and an inactive substitute to 2,081 people (average age 58). After 5 years, 57 of the lovastatin group had suffered a heart attack, compared with 97 for the inactive pill. (a) State the app

Hypothesis testing: differences in mean and differences in variance.

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

Sample proportions of fire truck accident rate

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 α = .01, did the yellow fire trucks have a significantly lower

Hugger Polls contends that an agent conducts a mean of 53 in-depth home surveys every week. A streamlined survey form has been introduced, and Hugger wants to evaluate its effectiveness. At the .05 level of significance, can we conclude that the mean number of interviews conducted by the agents is more than 53 per week?

Hugger Polls contends that an agent conducts a mean of 53 in-depth home surveys every week. A streamlined survey form has been introduced, and Hugger wants to evaluate its effectiveness. The number of in-depth surveys conducted during a week by a random sample of agents are: 53 57 50 55 58 54 60 52 59 62 60 60 51 59 56 At

Hypothesis Testing: Age of College Juniors

Develop a problem statement. Let's assume that the question deals with the age of college juniors. 1) Establish the null hypothesis (H0) and the alternate hypothesis (H1). 2) Select the level of significance, that is. 3) Select an appropriate test statistic. 4) Formulate a decision rule based on steps 1, 2,