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Descriptive Statistics

Make use of dummy variable in the regression analysis

First, explain in your own words (no direct quotes, please) what a dummy variable is and its purpose in regression analysis. Secondly, provide an example of where you might use a dummy variable from your own professional experience. Thirdly, briefly describe how you would implement a dummy variable in a data table you intend to

Relationship Between Sampling Mean and Population Mean

Drug manufacturer knows that for a certain antibiotics, the average number of doses ordered for a patient is 20. Steve Simmons, a salesman for the company, after looking at 1 day's prescription orders for the drug in his territory, announced that the sample mean for this drug should be lower. He said, "For any sample, the mean s

Introductory Statistics

Let x be a random variable representing dividend yield of Australian bank stocks. We may assume that x has a normal distribution with f$sigma f$ = 2.8%. A random sample of 16 Australian bank stocks has a sample mean dividend yield of 8.91%. For the entire Australian stock market, the mean dividend yield is f$mu f$ = 6.4%. If

Statistics 2

The marketing manager of a large supermarket chain would like to use shelf space to predict the sales of pet food. For a random sample of 12 similar stores, she gathered the following information regarding the shelf space, in feet, devoted to pet food and the weekly sales in hundreds of dollars. Store 1 2 3 4 5 6 Shelf

Differences in Descriptive and Inferential Statistics

Examine the differences between descriptive and inferential statistics. Address the following items: Describe the functions of statistics. Define descriptive and inferential statistics. Provide at least one example of the relationship between descriptive and inferential statistics.

Norms and Standardized Samples

Please help answer the following question. Provide at least 400 words in the solution. What is the relationship between a standardization sample and test norms?

Correlation Analysis for Birth Rate Variation

1. Data are gathered on 40 countries to study variations in birth rate. Consider an equation derived in the study: where: Y = birth rate per 1,000 population X = per capita income a. Identify the following: the independent and dependent variables the regression coefficient

Patterns in linear regression models

What pattern would you need to decide that the linear regression model is appropriate? What would you do if you found a curvilinear pattern or no pattern at all? Discuss how to calculate the best-fitting line in a scatter plot (regression analysis).

Constructing Graphic Representation of Random Samples

Question 1 To compare commuting times in various locations, independent random samples were obtained from the six cities presented in the "Longest Commute to Work" graphic on page 255 in your textbook. The samples were from workers who commute to work during the 8:00 a.m. rush hour. One-way Travel to Work in Minutes Atlanta Bo

Determining the Number of Trial Runs of a Chemical Process

A production supervisor at a major chemical company wishes to determine whether a new catalyst, catalyst XA-100, increases the mean hourly yield of a chemical process beyond the current mean hourly yield, which is known to be roughly equal to, but no more than, 750 pounds per hour. To test the new catalyst, five trial runs using

Contingency Table Approach and Probability

A laptop computer manufacturer sells a computer with a particular configuration. The manufacturer conducted a study on purchase intentions of consumers for this particular laptop with varying potential attributes. From the study it was found that 45% of consumers wanted a faster processor. 55% wanted a larger screen and 40% want

Probability and Marketing

A local beer company sells two types of beer, a regular brand and a light brand with 30% fewer calories. The company's marketing department follows its traditional strategy of targeting women beer drinkers with light beer and men beer drinkers with regular beer. To test the rationale for this strategy an intern at the company ra

Conduct hypothesis testing for the mean of two populations

Please help to answer questions A-D in the attachment. For questions A and B, would you use the use the t-test two sample assuming equal variances function? If not, what would you use? I'm not sure what the graphical method is to answer question C. What is it and how do you create it? Please show your calculations in exce

Statistics: Normal Probability

Please assist with the following question. Thanks in advance for your help! As players' salaries have increased, the cost of attending baseball games has increased dramatically. The file attached (BBCOST) contains the cost of four tickets, two beers, four soft drinks, four hot dogs, two game programs, two baseball caps, and t

Estimating the mean difference in weight gain

Based on a survey of 1,000 adults by Greenfield Online and reported in a May 2009 USA Today Snapshot, adults 24 years of age and under spend a weekly average of $35 on fast food. If 200 of the adults surveyed were in the age category of 24 and under and they provided a standard deviation of $14.50, construct a 95% confidence int

Hypothesis (Additional Help)

Using the telephone numbers listed in your local directory as your population, randomly obtain 20 samples of size. I have attached these numbers in an excel sheet. From each telephone number identified as a source, take the fourth, fifth, and sixth digits. a. Calculate the mean of the 20 samples b. Draw a histogram showing the

Predicting Price from Capacity

2. Disk drives have been getting larger. Their capacity in now often given in terabytes (TB) where 1 TB = 1000 gigabytes, or about a trillion bytes. A survey of prices for external disk drives found the following data: Capacity (in TB) Price (in $) .080 29.95 .120 35.00 .200 299.00 .250 49.95 .320 69.95 1.0 99.00

Statistical analysis relating to human resources

20. Although controversial and the subject of some recent lawsuits, some human resource departments administer standard IQ tests to all employees. The Stanford-Benet test scores are well modeled by a Normal model with mean 100 and standard deviation 16. If the applicant pool is well modeled by this distribution, a randomly sele

ANOVA Table and Null Hypothesis Testing

The attached data resulted from an experiment that utilized a completely randomized design, Complete the ANOVA table. I have attached the answer in table format as well; I want to understand how the answers were obtained and also test the null hypothesis. Treatment 1 Treatment 2 Treatment 3 3.3 5.1

Constructing a Cummulative Percentage Distribution

The following data represents the amount of soft drink in a sample of 50, 2 liter bottles (the data file with the info has also been attached): I need help: 1. Constructing a cumulative percentage distribution. 2. Based on the results of (a) and (b), does the amount of soft drink filled in the bottles concentrate around spe

Normal probability distribution of investments

An investment broker reports that the yearly returns on common stocks are approximately normally distributed with a mean return of 12.4 percent and a standard deviation of 20.6 percent. On the other hand, the firm reports that the yearly returns on tax-free municipal bonds are approximately normally distributed with a mean retur

Small Business Index Survey

Chapter 3 18 The U.S. Fish and Wildlife Service plans to study the fishing industry around Saginaw Bay. To do that, they decide to randomly select 5 fishing boats at the end of a randomly chosen fishing day and to count the numbers and types of all the fish on those boats. a) what kin