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# Descriptive Statistics

### 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.

### The solution gives detailed steps on determining slope and intercept on the regression line using excel.

A company has observed that there is a linear relationship between indirect labor expense (ILE) , in dollars, and direct labor hours (DLH). Data for direct labor hours and indirect labor expense for 18 months are given in the file ILE_and_DLH.xlsx Treating ILE as the response variable, use regression to fit a straight line t

### 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?

### The solution gives detailed steps on calculating t-statistic and p-value using t test for population mean when standard deviation is unknown.

Consider the e-billing case. The mean and the standard deviation of the sample of n = 65 payment times are = 18.7598 and s = 3.9494. Test H0: μ = 19.1 versus Ha: μ < 19.1 by setting α equal to .01 and using a critical value rule and assume normality of the population. (Round your "t" and "t0.01" answers to 3 decimal places

### Choosing a method to measure central tendency

All of the full questions (including methods to measure central tendency) are in the attached document.

### 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

### The solution gives detailed steps on calculating the conditional probability under different conditions using contingency tables.

In a large accounting firm, the proportion of accountants with MBA degrees and at least 5 years of professional experience is 0.75 times the proportion of accountants with no MBA degree and less than 5 years of professional experience. Furthermore, 35% of the accountants in this firm have MBA degrees, and 45% have less than 5 ye

### 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

### Exercise on Statistics

Attached is an exercise on Simple Linear Regression with accompanying pdf files.

### 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

### The solution gives detailed steps on computing different terms on descriptive statistics including standard deviation, proportion, percentile, probability and sample size.

Question 1 1. A major U.S. automaker has determined that the city mileage for one of its new SUV models is normally distributed with a mean equal to 15.2 mpg. A report issued by the company indicated that 22 percent of the SUV model vehicles will get more than 17 mpg in the city. Given this information, what is the city mileag

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

### The solution gives detailed steps on computing mean, median, mode, variance, standard deviation, range, coefficient of variation, and Z scores and performing relevant analysis.

I need assistance with the problem below. Thanks in advance! The Chocolate Chip file contains the cost (in cents) per 1-ounce serving for a sample of 13 Choclate Chip Cookies. The data is as follows (also see the attached file labelled chocolate chip cookies that is the only file needed) 54 22 25 23 36 43 7 43 25 47 24

### Gambling hypothesis test

I need help with an hypothesis test with an unequal sample.

### 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