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    Hypothesis Testing

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    Statistical Hypothesis Testing: Z test for Proportion

    Factories are being compared to see if there is a difference in the average defect rates of the chips they produce. In the first factory 250 chips are sampled, In the 2nd factory 350 chips are sampled. Proportions of defective chips are 4.0% and 6.0% respectively. Using a confidence level of 95%. Which statement is supported by

    Two Sample Test

    The mall has two stores, one located on Street 1 and other on Street 2. Tow stores are laid out differently but both store managers claim their layout maximizes the amounts customers will purchase on impulse. A sample of 10 customers at Street 1 store revealed they spent the following amounts more than planned: 17.5, 19.73, 12.6

    Comparing Samples

    The manager of a package courier service believes that packages shipped at the end of the month are heavier than those shipped early in the month. As an experiment, he weighed a random sample of 20 packages at the beginning of the month. He found that the mean weight was 20.25lb and that the standard deviation was 5.84 lb. Ten p

    Hypothesis Testing and finding P-Value: Crime Example

    The federal government recently granted funds for a special program designed to reduce crime in high-crime areas. A study of the results of the program in eight high-crime areas of Miami, Florida, yielded the following results. Number of Crimes by Area A B C D E F G H Before 14 7 4 5 17 12 8 9 Aft

    Five step model of hypothesis testing for a counseling psychologist

    A counseling psychologist is interested in determining whether the perception of a counselor's expertise is affected by the approach the counselor utilizes. In particular, the counseling psychologist is interested in contrasting a rational-emotive approach with a client-centered approach using an instrument that rates perceptio

    Forecasting Hotel Check-Ins Example Problem

    Given the following data on hotel check-ins for a 6-month period: July: 10 rooms August: 15 rooms September: 12 rooms October: 20 rooms November: 18 rooms December: 24 rooms With alpha = 0.2, what is the simple exponential smoothing forecast for October? Put your answer in the form xx.x with no additional numbers o

    Chocolate Bar Taste Test

    The following data resulted from a taste test of two different chocolate bars. The first number is a rating of the taste,which could range from 0 to 5, with a 5 indicating the person liked the taste. The second number indicates whether a "secret ingredient" was present. If the ingredient was present a code of "1" was used

    Number of Crimes by Area

    The Federal Government recently granted funds for a special program designed to reduce crime in high-crime areas. A study of the results of the program in eight high-crime areas of Miami, Florida, yielded the following results. Number of Crimes by Area A B C D E F G H Before 14 7 4 5 17 12

    Hypothesis Testing

    The cost of an e-commerce website can vary a great deal. A market research team hypothesized that the cost of an average website is $3500. Ho mean = $3,500 H1 mean ? $3,500 The sample data obtained showed the following costs: 2000, 3000, 3500, 3900, 6000, 7000, 10000, 12000, 14900, 19900, 6990, 9990, 2400 I n

    Sampling Method and P-Values

    See the attached file. A sociologist wanted to determine which academic subject high school students preferred. The hypotheses she wishes to test are: Ho: The percentage of female high school students who prefer mathematics is equal to the percentage of male students who prefer mathematics. H1: The percentage of female

    Probability Distribution and P-Values

    See the attached file. A supermarket advertises that the waiting time spend by customers waiting in line at the cash register is uniform between 0 and 6 minutes. A number of customers complain that they wait in line too long for this to be true. Joel, the manager, decides to test whether the complains are justified by testing t

    Probability and P-Values

    See the attached file. There are two boxes, Box A and Box B. Box A has 40 tags with the number 1, 50 tags with the number 10, and 10 tags with the number 100. Box B has 40 tags with the number 100, 50 tags with the number 10, and 10 tags with the number 1. A box is picked at random and exactly one tag is drawn at random from th

    Hypothesis Testing of Frequency of Drug Use

    Calculate and interpret the appropriate statistical test to determine the relationship between the following two variables. Use the five-step model of hypothesis testing to draw conclusions at the .05 level of significance Class Frequency of Drug Use Freshman Sophomore Junior Senior Never 16 8 30 28 1 or 2 20 25 22 10

    Hypothesis Testing Question

    Calculate and interpret the appropriate statistical test to determine the relationship between the following two variables. Use the five-step model of hypothesis testing to draw conclusions at the .05 level of significance Gender College Major Male Female Psychology 11 9 Educatio

    Determining whether to accept or reject a hypothesis

    A counseling psychologist is interested in determining whether the perception of a counselor's expertise is affected by the approach the counselor utilizes. In particular, the counseling psychologist is interested in contrasting a rational-emotive approach with a client-centered approach using an instrument that rates perceptio

    Value of test statistic

    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 conclude that college students watch fewer

    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