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Hypothesis Testing

Hypothesis Testing Population Proportions

Two popular drugs used for the treatment of depression are Resithan and Exemor. A random sample of 588 depressed individuals is selected and treated with Resithan, and 201 find relief from their depression. A random sample of 417 depressed individuals is independently selected from the first sample and treated with Exemor, and 1

Hypothesis Testing and P-Values

The General Social Survey is an annual survey given to about 1500 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 264 college graduates surveyed

Hypothesis Testing: one-tailed test

A study conducted by the research department of a pharmaceutical company claims that the annual spending (per person) for prescription drugs for allergy relief, , is greater than or equal to the annual spending (per person) for non-prescription allergy relief medicine, . A health insurance company conducted an independent study

Hypothesis testing statistics

Chapter 10 in your text, exercise 10.24?High vs. Low Pressure Sales Tactics (Two Way ANOVA). Use Table 10.24 and Figure 10.13. Complete the exercise from the data given and answer all of the questions in a written summary. (Cut and paste any EXCEL data that you wish to discuss). See attached file for full problem descriptio

Hypothesis Testing and Levels of Significance: Pharmaceuticals

A study conducted by the research department of a pharmaceutical company claims that the annual spending (per person) for prescription drugs for allergy relief is greater than or equal to the annual spending (per person) for non-prescription allergy relief medicine. A health insurance company conducted an independent study and c

What is the test statistic? What is the critical value?

A manufacturer of nickel-hydrogen batteries randomly selects 100 nickel plates for test cells, cycles them a specified number of times, and determines that 14 of the plates have blistered. Does this provide compelling evidence for concluding that more than 10% of all plates blister under such circumstances using a significance l

positive critical value of a test

A random sample of 145 recent donations at a certain blood bank reveals that 74 were type A blood. Does this suggest that the actual percentage of type A donors differs from 40%, the percentage of the population having type A blood? Carry out a test of the appropriate hypotheses using a significance level of 0.01. Let p re

Least Squares Fitting

In fitting a least squares line to n=15 data points, the following quantities were computed: SSxx=55, SSyy=198, SSxy=-88, x-bar=1.3, and y-bar=35. Determined the following: y=B0+B1X y=37.08-1.6X SSE=57.2 S squared = 4.4 1. Find 90% confidence interval for B1/Interpret answer 2. Find 90% prediction interval for Y when

Probability Problems

#3 - Use your own paper as an answer sheet. Show all mathematical calculations. No partial credit will be given if work is not shown. A calculator will be required to complete the exam. 1. Find the 90% confidence interval for a population mean if the sample mean is 21.6 with a standard deviation of 2.8 for a sample of 35.

Business Plan - Statistics Section

A. Clearly define the dependent and independent variables that are the focus of the team's study. The dependent variable is the variable whose value is the result or is a function of the control or independent variables. b. State the null and alternative hypotheses and the theories that support these hypotheses that will be t

Hypothesis Testing Question

3. The director of admissions at the University of China is concerned about the high cost of textbooks for the students each semester. A sample of 20 students enrolled in the university indicates that X (bar) = $316.4 and s = $43.20. Answer the following questions in detail by using Excel.

Step-wise answer to Testing of hypothesis problems

A decade-old study found that the proportion, p, of high school seniors who believed that "getting rich" was an important personal goal was 75%. A researcher decides to test whether or not that percentage still stands. He finds that, among the 250 high school seniors in his random sample, 182 believe that "getting rich" is an im

What does it mean to decrease the level of significance?

If we decrease the level of significance a (alpha) from 0.05 to 0.01, that means we are: A. More willing to accept a type II error; B. More willing to accept a type I error; C. Less willing to accept a type I error; D. None of the above.

Testing of Hypothesis with a Student T Test

See attached file for full problem description. 15. Injuries to Major League Baseball players have been increasing in recent years. For the period 1992 to 2001, league expansion caused Major League Baseball rosters to increase by 15%. However, the number of players being put on the disabled list due to injury increased 32%

ANOVA Calculation: Research Summary

1. Choose one article (link provided below) to examine and work through as an ANOVA calculation. In this regard, remember the goal will be to work through an ANOVA test to compare the means of three or more groups of data. If the article your group selected does not have enough data to complete an ANOVA calculation, please feel

Z statistic and the critical value: one-tailed test of hypothesis

1) An automobile assembly line operation has a scheduled mean completion time, mean, of 12.8 minutes. The standard deviation of completion times is 1.2 minutes. It is claimed that, under new management, the mean completion time has decreased. To test this claim, a random sample of 44 completion times under new management was tak

Test of hypothesis-Z statistic and p-value

A manufacturer claims that the mean lifetime, mean, of its light bulbs is 52 months. The standard deviation of these lifetimes is 7 months. Ninety bulbs are selected at random, and their mean lifetime is found to be 55 months. Can we conclude, at the 0.05 level of significance, that the mean lifetime of light bulbs made by this

Is there difference in the balance time across the practice groups?

A short study was conducted to determine if balance could be improved with practice technique. After obtaining the length of time (in minutes) a subject can balance on 1 leg on a 12 inch wooden block, subjects were randomly allocated to 4 practice groups. Each group was taught different technique to improve balance. Subjects wer

T test

To investigate the efficacy of a diet, a random sample of 16 male patients is drawn from a population of adult males using the diet. The weight of each individual in the sample is taken at the start of the diet and at a medical follow up 4 weeks later. Assuming that the population of differences in weight before versus after the

Using the Five-Step Hypothesis Testing

Use the five-step hypothesis testing procedure to solve the following exercises. 21. The management of Discount Furniture, a chain of discount furniture stores in the Northeast, designed an incentive plan for salespeople. To evaluate this innovative plan, 12 salespeople were selected at random, and their weekly incomes before

AIU - Testing of Hypothesis (Job Satisfaction)

Using AIU's large database of survey responses from the AIU data set, complete the following: Perform hypothesis testing on one variable's data. (Choose either the intrinsic or extrinsic column.) Perform a t-test by formulating a null and an alternative statement, choosing an acceptable significance value, selecting the test s

Statistics matching question: definitions/examples of statistical terms

The mean number of college credits earned in the fall by students at City University is to be estimated by determining the mean number of credits earned in the fall semester by the 100 students enrolled in statistics 202. Data (one piece of) Data (set of) Experiment Parameter Population Sample Statistic Variable A

Hypothesis Testing - Real Life Example

Make a decision regarding the null hypothesis based on the sample information and interpret the results of the test, state whether we proved or disproved the null hypothesis and why the data proves this. A company needs to purchase company cars for their sales staff. They contacted their local Ford dealership and inquired as

Statistical Difference Formula

I am looking to design something in Microsoft Access, but not sure how to do the two statistical calculations. For example, assume there are two columns of data labeled January and February. In each of these columns are the numbers 0-4. Where 0=Blank Response, 1=Poor, 2=Fair, 3=Good, 4=Excellent I want to know if th

Hypothesis test for the difference of population means: Paired comparisons

Attached is 2 slides on powerpoint. The 1st slide is the problem and the 2nd slide is the answer format. Answer 3 is completed because it requires the use of a t test with degree of freedom that equals 11. Attached also is the excel data Please help with 1,2,4,5 and 6 only 1) eg: u=0 or u>0 etc 2) same as 1 3) answere

Hypothesis test for the population mean: Z test

See full problem description. A leasing firm claims that mean number of miles driven annually, mu, in its leased cars is less than 12480 miles. A random sample of 16 cars a leased from this firm had a mean of 11075 annual miles driven. It is known that the population standard deviation of the number of miles driven in cars fr