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    Hypothesis Testing

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    Hypothesis Problem

    A recent national survey found that high school students watched an average (mean) of 6.8 videos per month. A random sample of 36 college students revealed that the mean number of videos watched last month was 6.2, with a standard deviation of 0.5. At the .05 significance level, can we concluded that college students watch fewer

    Solving General Statistics Problems

    Am having difficulty plugging in the correct values into the formulas to be sued. If you can please provide step by step work out of the following problems. Begin with formula to be used and then work out so i can see where values go I would appreciate it. 2) A biologist suspected that in the 20-24 age group, males have a hi

    Type I or Type II errors?

    1) What is more important for the researcher to be concerned about in a study, Type I or Type II errors? Why? How does the type of data collected and the way in which the data is collected affect the possibility of Type I or Type II error? 2) Give two examples when practical significance would outweigh statistical signific

    Significance, Hypothesis Test

    1. In research, one often hopes to be able to state results using a confidence level that the results are valid of 90% or more. To test results to determine the confidence level, what is the significance of locating the test statistic in the tail that has a probability less than ά, which implies a confidence level of 1-(alp

    Hypothesis test

    Two popular drugs used for the treatment of depression are Resithan and Exemor. A random sample of 451 depressed individuals is selected and treated with Resithan, and 204 find relief from their depression. A random sample of 598 depressed individuals is independently selected from the first sample and treated with Exemor

    Hypothesis test for the difference of population means: Paired comparisons

    Hypothesis test for the difference of population means: Paired comparisons A personal computer manufacturer is interested in comparing assembly times for two keyboard assembly processes. Assembly times can vary considerably from worker to worker, and the company decides to eliminate this effect by selecting a random sample of

    Type I vs. Type II Errors

    1) What is more important for the researcher to be concerned about in a study, Type I or Type II errors? Why? How does the type of data collected and the way in which the data is collected affect the possibility of Type I or Type II error? 2) Give two examples when practical significance would outweigh statistical significan

    Intro to Stats: review question..

    It is believed that more than 50% of recovering alcoholics exhibit high levels of depression. A psychological test known as the DACL was given to a random sample of 100 recovering alcoholics, and it was found that 55 had above average depression levels. Does the sample result indicate that the proportion of recovering alcoholi

    Bell curve, standard deviation & statistical significance

    1) In research we often rely on the 68-95-99.7 rule. Discuss how this can be applied to make statements about the number of data values below 1, 2, or 3 standard deviations from the mean. Give an example of application of this rule. 2) In a research study, what does statistically significant mean? How are decisions made on d

    Hypothesis Testing : Proportion and Solutions in Research Issue

    A comparison between products manufactured in China VS Mexico and their perceived quality to the US consumer based on manufacturing location. We can state that 75% of American's perceive that a product (non-electronic) manufactured in Mexico is of better quality than a product manufactured in China. To do the testing we just ask

    Difference in Population Means - HT

    Fairfield Homes is developing two parcels near Pigeon Fork, Tennessee. In order to test different advertising approaches, they use different media to reach potential buyers. The mean annual family income for 75 people making inquiries at the first development is $150,000, with a standard deviation of $40,000. A corresponding sam

    Tire Brands Testing

    A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Tread wear can vary considerably depending on the type of car, and the group is trying to eliminate this effect by installing the two brands on the same random sample of 8 cars. In particular, each car has one tire of each brand o

    Null hypothesis and the alternative hypothesis.

    For the following statement, write the null hypothesis and the alternative hypothesis. Then, label the one that is the claim being made. The dean of a major university claims that the mean time required to earn a master's degree is 3.4 years.

    Test Statistic - Sample Size for a Restaurant

    A census is a ________________ of an entire population A restaurant claims that its speed of service time is less than 18 minutes. A random selection of 36 service times was collected, and their mean was calculated to be 17.7 minutes. Their standard deviation is 3.1 minutes. Is there enough evidence to support the claim at al

    Hypothesis & Variables

    1) Define what a hypothesis is and discuss the relationship between hypothesis testing and statistics. 2) List the five steps required to test a hypothesis of the mean. Be sure that all steps are in the correct sequence. Explain why the fifth step is the most important. 3) Discuss what independent and dependent variables

    Test Bus Companies Claim

    A bus company claims that the mean waiting time for a bus during rush hour in less than 7 minutes. A random sample of 20 waiting times has a mean of 5.2 minutes with a standard deviation of 2.1 minutes. At a= 0.01, test the bus companies claim. Assume the distribution is normally distributed. Include curve. Write conclusion

    Testing the Manufacturing Quality Process

    A manufacturer receives an order for light bulbs. The order requires the bulbs have a mean life span of 750 hours. The manufacturer selects a random sample of 25 light bulbs and find they have a mean life of 745 hours with a standard deviation of 15 hours. Test to see if the manufacturer is making acceptable light bulbs. Ass

    MacBurger and Golf Cart Statistics Questions

    1. The MacBurger restaurant chain claims that the waiting time of customers for service is normally distributed, with a mean of 3 minutes and a standard deviation of 1 minute. The quality-assurance department found a sample of 50 customers at the Warren Road MacBurger that the mean waiting time was 2.75 minutes. At the .05

    P-Value of a tossed coin

    A coin tossed 100 times and 530 heads appear. At a=0.05, test the claim that this is a non biased coin. Use a P-Value. Does this suggest the coin is fair? Show all of your work including curve and make your conclusion in verbiage a layman can understand.

    Z Test for proportion

    The engineering school at a major university claims that 20% of its graduates are women. In graduating class of 210 students, 58 were women. Does this suggest that the school is believable? Use a= 0.05. Show all of your work, including curve, and make your language a layman can understand

    Mean Lifetime of a Tire

    A trucking firm suspects that the mean lifetime of a certain tire it uses is less than 35000 miles. To check the claim the firm randomly selects and test 54 of these tires and gets a mean lifetime of 34,570 with a standard deviation of 1200 miles. At a=0.05, test the trucking firms claim. Show all of your work, including the

    Hypothesis Testing: Simple Analysis

    Please see the small data attached. I need analysis showing following. 1) Mean calculation and T test calculation based on the data. I want ALL the steps on how you got the answers please. 2) 2 graphs made by excel showing comparison of mean between the control and unibrow group. and the other needs to show the rejec

    Claim of Independence

    The contingency table below shows the results of a random sample of 200 state representatives that was conducted to see whether their opinions on a bill are related to their party affiliation Party Approve Disapprove No Opinion Republican 42 20 14 Democrat 50 24 18 Independent 10

    Test Statistic for Medical Researchers

    A medical researcher suspects that the pulse rate of smokers is higher than the pulse of non smokers. Use the sample statistics below to test the researchers suspicion. State your hypothesis, draw your curve, label your critical values and your test statistic, state your decision to accept or reject. Write your conclusion in

    Test Statistic for specialized medicine

    In a survey of 500 doctors that practice specialized medicine, 20% felt that the government should control health care. In a sample of 800 doctors that were general practitioners, 30% felt the government should control health care. Test the claim that there is a difference in the proportions. State your hypothesis draw your c

    Z Value and Test Statistic of a population

    Assume that the data has a normal distribution and the number of observations is greater than fifty. Find the critical z value used to test the null hypothesis. =0.05 for a left-tailed test. -1.645 1.96 1.645 -1.96 Use the given information to find the P-value. The test statisti