1) In what ways is the t distribution similar to the standard normal distribution? In what ways is the t distribution different from the standard normal distribution? How does the formula for the t test differ from the formula for the z test? 2) Choose a variable. Before collecting the data, decide what a likely average migh
A sample of 25 concession stand purchases show a mean purchase of $5.29 with a standard deviation of $3.02. However, a later showing of the same movie, a sample of 25 purchases where the mean was $5.12 with a standard deviation of $2.14. The means appear to be very close, but not the variances. At alpha = .05, is there a dif
Construct a hypothesis test for the population mean using a t-test for a coin operated drink machine.
A coin-operated drink machine was designed to discharge a mean of 8 ounces of coffee per cup. In a test of the machine, the discharge amounts in 20 randomly chosen cups of coffee from the machine were recorded. The sample mean and sample standard deviation were 8.08 ounces and .13 ounces, respectively. If we assume that the dis
Suppose that a one-tailed t-test is being applied to find out if the population mean is less than $212. The level of significance selected is 0.01 and 26 accounts are sampled. What is the critical value? A machine is set to fill the small size packages of M&M candies with 56 candies per bag. A sample revealed: 3 bags of 5
The data that you will be using for this exercise came from a survey of two insurance carriers. The first carrier (C1) was compared against the second competitor (C2). The insurance company management team wants to know how Carrier 1 compared to the second carrier. Data from 159 respondents are included. All of the 5 quest
You are provided with the male and female unemployment data for the 1960-2005 periods. Using these two samples, determine whether the data support the conclusion that female unemployment rate is higher than the male unemployment rate. Use 0.01 level of significance. INSTRUCTIONS 1. Go to the blackboard, assignment section a
The Business Administration department at a local university delivers some of its courses using online instruction. Of the two statistics courses offered, one is delivered online and the other is delivered on campus. Eighteen pairs of students are selected, who are well matched on a number of years and grades of mathematics cour
A hypothesis states a difference exists between two populations. Sometimes this is an obvious conclusion because the means will be very different. For example, if I gave math tests to boys and girls and the boys on average scored 20 points better than the girls, I know that is enough of a difference to conclude with accuracy tha
If a regression coefficient passes the t-test, it means that a. the regression equation is valid. b. the regression coefficient is significantly different from zero. c. the regression coefficient can be used for forecasting. d. the regression coefficient should be included in the regression equation.
Please see attached file for full problem description. ? What are Type I and Type II errors? Why do you want to avoid them? ? What is effect size and what does it tell you about your findings? ? What is power of a statistical test and what factors affect it? ? When is it necessary to conduct a t test? ? What are the "
Compare the two-sample independent t test to the paired t test. Can you please compare and contrast this for me?
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
Step by step method for testing the hypothesis under 5 step approach is discussed here. Excel template for each problem is also included. This template can be used to obtain the answers of similar problems.
It seems these days that college graduates who are employed full-time work more than 40-hour weeks. Data are available that can help us decide if this is true. A survey was recently sent to a group of adults selected at random. There were 15 respondents who were college graduates employed full-time. The mean number of hours work
In recent years, a growing array of entertainment option competes for consumer time. By 2004, cable television and radio surpassed broadcast television, recorded music, and the daily newspaper to become the two entertainment media with the greatest usage. Researchers used a sample of 15 individuals and collected data on the hour
Periodically Merrill Lynch customers are asked to evaluate Merrill Lynch¯Financial consultants and services (2000 Merrill Lynch Client Satisfactory Survey). Higher ratings on the client satisfaction survey indicate better service with 7 the maximum service rating. Independent samples of service ratings for two ¯Financial cons
If anyone could walk me through the below problem it would be greatly appreciated! Thanks, Brian A magazine is considering the launch of an online edition. The magazine plans to go ahead only if it's convinced that more than 25% of current readers would subscribe. The magazine contacts a simple random sample of 500 curr
How does statistics enrich and represent the results of a study? How can statistics be used to misrepresent the results of a study? What is the advantage or disadvantage with using a one-tailed t-test?
T-tests, independent samples, paired and one-way t-tests expalined. When shoud they be used and what kind of data should they be used on?
The amount of money out of income spent on housing is an important component of the cost of living. The total costs of housing for homeowners might include mortgage payments, property taxes, and utility costs (water, heat, electricity). An economist selected a sample of 20 homeowners in New England and then calculated these tota
A personal computer manufacturer is interested in comparing assembly times for two keyboard assembly processes. Process 1 is the standard process used for several years, and Process 2 is an updated process hoped to bring a decrease in assembly time. Assembly times can vary considerably from worker to worker, and the company deci
A shipment of crankshafts is believed to be defective. A simple random sample of 16 is drawn from a large shipment. Check to see if the sample is any different from the assumed population mean of 224. 224.12 223.960 224.098 224.001 224.089 224.057 224.017 223.987 223.913 223.982 223.976 223.999 223.989 223.902 2
#5 In an investigation of the possible brain damage due to alcoholism, CAT scans were used to measure brain densities in eleven chronic alcoholics. Each alcoholic was paired with a non-alcoholic control selected to match the alcoholic on age, gender, education and other factors. The brain densities are given in the table.
Construct a 95% confidence interval for the true population mean of donut weights, and then explain whether or not she will be in trouble.
1. Dunkin Donuts advertises that a dozen of their donuts weighs about 43 oz. A certain baker has figured out that she can stay out of trouble with her manager if each donut weighs about 3.6 oz. To test her donut-making process, she randomly selects thirty-one donuts after baking and weighs them. The average of the sample
As a researcher I would like to evaluate the effectiveness of the workout programs purchased. This done by comparing the weight loss for a sample size of n=1 person who uses the bean workout program for a period of 5 days a week, and for a sample size of n=1 who uses the x90u workout program for a period of 3 days a week. At t
1. What factor determines whether you should use a z-score or a t statistic for a hypothesis test? 2. Several factors influence the value obtained for a t statistic. Some factors affect the numerator of the t statistic and others influence the size of the estimated standard error in the denominator. For each of the following
The average electric bill for residents of Anderson creek is at least 52.98 per month. Develop the appropriate null and alternative hypothesis. What is the type I error in this situation? What is the type II error in this situation? Full time PhD students receive an average salary of 12, 837 according to the US Department of
The average annual rent for office space in Tampa was 17.63 per square foot. A real estate agent selected a random sample of 15 rental properties and found that the mean rent was 18.72 per square foot, and the standard deviation was 3.64. At ?=.05, test the clan that there was no difference in the rents. A report by the NCAA
Determine what is the most usual and common characteristic of Aishka, her height or weight when compared with Puerto Rican women.
Aishka is 67-inch-tall, and she weighs 135 lbs. If the medium height of Puerto Rican women has a normal distribution with µ = 65 inch tall with standard deviation of 2.5 inches, and the weight of the women has a normal distribution µ = 125 lbs with a standard deviation of 10 lbs. Determine what is the most usual and common cha
A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Though the two brands have been comparable in the past, some technological advances were recently made in the Brand 1 manufacturing process, and the consumer group is testing to see if Brand 1 will outperform Brand 2. Tread wear c
86 total students were asked: Do you feel sleep deprived? Mean # hours of sleep Yes (51 students) 5.94 No (35 students) 7.06 Ho: mean = 7 hours of sleep, no feeling of sleep deprivation Ha: mean = < 7 hours of sleep, feeling of sleep deprivation Ple