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    Descriptive Statistics

    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

    ANOVA Study on Egg Housing Systems

    A study of four different types of egg housing systems was performed. The four egg housing systems were cage, barn, free range, and organic. In addition to housing system, the researchers also determined the weight class (medium or large) for each sampled egg. The data on whipping capacity (percent overrun) for the 28 sampled e

    Statistics Data Set

    1. The following data set represents the repair costs (in dollars) for a random sample of 30 dishwashers. 41.82 52.81 57.80 68.16 73.48 78.88 88.13 88.79 90.07 90.35 91.68 91.72 93.01 95.21 95.34 96.50 100.05 101.32 103.59 104.19 105.62 111.32 117.14 118.42 118.77 119.01 120.70 140.52 141.84 147.06 (a) Find the point esti

    Calculating house prices with sample statistics

    Hi, I want the answers for: 1-The mean price of new homes from a sample of houses is $155,000 with a standard deviation of $15,000. The data set has a bell-shaped distribution. Between what two prices do 95% of the houses fall? Refer to the sample statistics of Exercise 5 and use z-scores to determine which, if any, of th

    Creating null and alternative hypotheses

    Question 3 State the null and alternative hypotheses for each of the following: a. You want to show an increase in buying and selling of single-family homes this year when compared with last year's rate. b. You are testing a new recipe for "low-fat" cheesecake and expect to find that its taste is not as good as traditional ch

    Normally Distributed Grades

    See the attachments. Exercises 2.16, 2.20, 2.24, 2.26 (b, d) Exercises 4.10 (a,d), 4.14, 4.20, 4.24, 4.32, 4.42, 4.50.

    Surveys, sampling method and categorical data

    Chapter 3 & 4 Sample Problems Chapter 3 5. GFK Roper Consulting conducts a global consumer survey to help multinational companies understand different consumer attitudes throughout the world. In India, the researchers interviewd 1000 people aged 13-65 . Their sample is designed so that they get 5

    calculating probability and checking independence

    Chapter 7 Sample Problems 41. A company has recently replaced their e-mail server because previously mail was interrupted on about 15% of workdays. To see how bad the situation was, calculate the probablity that during a 5-day work week, there would be an e-mail interruption. A) On Monday and again on Tuesday?

    Determining the sample size in the given case

    If the manager of a paint supply store wants to estimate the mean amount of paint in a 1-gallon can to within +/- 0.004 gallon with 95% confidence and also assumes that the standard deviation is 0.02 gallon, what sample size is needed? Please answer in excel using functions.

    Confidence Interval Estimate: Social Media Example

    In a survey of 1200 social media users, 76% said okay to friend co-workers, but 56% said it is not okay to friend co-workers. (Data extracted from "Facebook Etiquette at work," USA Today, March 24, 2010, p.1B). a. Construct a 95% confidence interval estimate for population proportion of social media users who would say it is

    Relationship: Correlations and Regressions

    Your final project entails systematic extraction of decision-aiding insights from a dataset (SampleDataSet.xlsx) provided to you in the Doc Sharing area. The goal of this project is to provide you with hands-on experience in conducting and interpreting different types of statistical analysis. The focus of your analysis will be o

    Statistics -savings rates in the US

    The significant decline of savings in the United States from the 1970s and 1980s to the 1990s and 2000s has been widely discussed by economists (money.cnn.com, June 30, 2010). According to the Bureau of Economic Analysis, the savings rate of American households, defined as a percentage of the disposable personal income, was 4.20

    Finding the Labor Hours in the Given Case

    The first unit of a product took 832 hours to build, and the learning rate is 90%. How long will it take to make the 20th unit? Estimated labor requirements to build 20th unit =________________hours.

    The solution gives detailed discussion on a study using Chi Square test.

    Describe a study you might design that could use the Chi Square statistic. What are the variables? What are the null and alternative hypotheses? Why would the Chi Square test be appropriate for this design? What would the Chi Square statistic indicate in relation to your research question? What would it not indicate? Be specific

    T-Test for Dependent Groups

    See the attached file(s). Questions: t-test for dependent groups 1. What are the two groups whose results are reflected by the t ratios in Tables 2 and 3? 2. Which t ratio in Table 2 represents the greatest relative or standardized difference between the pretest and 3 months outcomes? Is this t ratio statistically signi

    Statistics Pitfalls

    Explain/discuss each pitfall and how it might impact good problem solving in the business environment. 1. Making conclusions about a large population from a small sample 2. Making conclusions from nonrandom samples 3. Attaching importance to rare observations 4. Using poor survey methods