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Descriptive Statistics

Determining a Difference in Means

The operations manager at a light bulb factory wants to determine whether there is a difference in the average life expectancy of bulbs manufactured on two different types of machines. The process standard deviation of Machine I is 110 hours and of Machine II is 125 hours. A random sample of 25 lights bulbs obtained from Machi

Sample Distribution and Normal Distribution

For a sample size 16, the sampling distribution of the mean will be approximately normally distributed: A. regardless of the shape of the population B. if the shape of the population is symmetrical C. if the sample standard deviation is known D. if the sample is normally distributed

Poisson Distribution and Interpretation of the Mean

The local police department must write on average 5 tickets a day to keep department revenue at budgeted levels. Suppose the number of tickets written per day follows a Poisson distribution with a mean of 6.5 tickets per day. Which of the following statements is the best interpretation of the value of the mean? A. The number

Describing the the Shape of a Distribution

The following is a five-number summary calculated from observations of the percentage of calories that come from fat in 23 items advertised as "reduced" fat from a sample of fast food chain restaurants. Form the box-and-whisker plot, select the phrase below which best describes the shape of the distribution. 15 20 22

Solving for the Mode

56 21 38 17 15 67 45 48 60 56 22 53 37 17 50 92 39 16 59 73 17 31 28 51 74 42 31 What is the mode of the array above? (show the answer rounded to the nearest whole number) A. 17 B. 31 C. 42 D. 56

Salaries of baseball players

I would like your HELP in answering these questions. The questions are related to the same subject SALARIES OF BASEBALL PLAYERS; 1. Are you looking at average teams, payrolls or individual player's salaries? I would answer TEAMS SALARIES 2. And if the latter, then what is the logic for any variation? 3. Is there a caus

Descriptive Statistics : Mean, Median, Mode and Standard Deviation

Please see the attached file for the fully formatted problems. Unit 9: Critical Thinking Exercise Data Collection and Data Analysis The Tastee-Yummy Dog Bone Company has developed four new commercials for their line of flavored dog cookies. Before selecting one of the commercials for production, they conducted research to a

Production Department of NDB Electronics

The production department of NDB Electronics wants to explore the relationship between the number of employees who assemble a sub-assembly and the number produced. As an experiment, two employees were assigned to assemble the sub-assemblies. They produced 15 during a one-hour period. Then four employees assembled them. They

Describing, Exploring, and Comparing Data

1.Senator Hayes is considering a a run for the U.S. presidency, but she is only 35 years of age, which is the minimum required age. While investigating this issue, she finds the ages of past presidents when they were inaugurated, and those ages are listed below. Using the ages listed find the (a) mean; (b) median; (c) mode; (d)

Scatter Diagram for "Best Small Companies" Sales and Earnings

A recent article in Business Week listed the "Best Small Companies." We are interested in the current results of the companies' sales and earnings. A random sample of 12 companies was selected and the sales and earnings, in millions of dollars, are reported below. Sales Earnings

Statistics - Descriptive Data

Kimble Products: Is There a Difference In the Commissions? At the January national sales meeting, the CEO of Kimble Products was questioned extensively regarding the company policy for paying commissions to its sales representatives.The company sells sporting goods to two major markets. There are 40 sales representatives who

Sexually Transmitted Diseases and Statistical Analysis

General K. is concerned about sexually transmitted disease (STD) among the troops. In random inspection of 100 soldiers, 31 were found to have a venereal disease. To reduce the incidence, soldiers were shown an educational film on preventing STDs. In a second inspection of 200 soldiers, 43 had STDs. Calculate the following s

Length of time to complete 1040 tax form

According to an IRS study, it takes an average of 330 minutes for taxpayers to prepare, copy, and electronically file a 1040 tax form. A consumer watchdog agency selects a random sample of 40 taxpayers and finds the standard deviation of the time to prepare, copy, and electronically file form 1040 is 80 minutes. a) What assum

Calculating A-C as described

A study is made by the recording industry in the US of the number of music CDs owned by senior citizens and young adults. The information is reported below Seniors 28 35 41 48 52 81 97 98 98 99 118 132 133 140 145 147 153 158 162 174 177 180 180 187

Stats for social sciences

Data collected by the highway patrol indicate that the average speed on the stretch of an interstate is 63mph with a standard deviation of 15. What is the likelihood of observing a vehicle traveling 80 mph or more?

Descriptive Statistics Case Studies

What are the standard deviations of the returns for stocks A and B? Suppose you want to use this history as a guide to making an investment decision for the long run. Based on this history, and assuming that standard deviation of return is the appropriate measure of risk, does it make any differ

How could you use descriptive statistics at work?

1. How could you use descriptive statistics at work? 2. How could you use descriptive statistics in your personal life? 3. The median home price in your area has increased in the last 10 years, how does this differ from the mean home price in your area? 4.When might coefficient of variation be a better measure of dis

Weighted percentages

A business operates with 9 locations. Each year, each location is allotted an overtime budget based on the previous years' activity. The total overtime budget for all 9 locations is $10 million. Each activity is also weighted more in the overtime budget. ( ex: production numbers a weighted more than sales because production mos

Public Debt in Germany

It is not clear what data is being measured here and I do not understand the missing variable information. I need to prepare a brief summary outline with any important trends. I am not clear on this case study, I am very confused. When Germany was reunited after the Berlin wall fell, two dramatically different social, econo

Finite math/business analysis 7 Multiple choice questions on statistics

1.Those methods involving the collection, presentation, and characterization of a set of data in order to properly describe the various features of that set of data are called a. statistical inference. b. the scientific method. c. sampling. d. descriptive statistics. 2. Which of the following is most likely a parameter a

Manipulated independent variable

An example of a manipulated independent variable might be ___________ a) The amount of sensory deprivation given a participant, b) A participant's religious affiliation, c) A student participant's hallucinations in response to severe sensory deprivation, d) A retarded child's behavior after a session of relaxation t

Stratum weights for proportional allocation

A financial analyst is interested in estimating the average amount of a foreign loan by U.S. banks. The analyst believes that the amount of a loan may be different depending on the bank, or, more precisely, on the extent of the bank's involvement in foreign loans. The analyst obtains the following data on the percentage of pro

Statistical Methods

I am in a peer/mentor group. We are meeting to discuss statistical methods. I need to discuss the goals of two statistical methods. The statistical methods are to be selected by you. What are some statistical methods? What does each method attempt to accomplish? I only need to address two.

Discuss: Research Trends and Questions

I am having difficulty creating a question with this data. I am to create a presentation that is an hour and a half long. So I am thinking of formulating one broad question with three sub questions. Can someone help me? Thank you.

Independent variable involved?

Suppose you were interested in studying sexism. You tell half of your participants that an essay was written by "John" and the other half of your participants that the essay was written by "Joan". Participants then grade the essay. Broadly speaking, your approach to manipulating your independent variable involves a. Prese

Compare auditory abilities of blind versus normally sighted rats

A neuropsychologist compare the auditory abilities of blind versus normally sighted rats. He predicted that the visually impaired rats would have better auditory development than normally sighted rats. He raises two groups of rats for a year (one normally sighted, one blind) and assessed auditory development by examining the n

Two Statistics Problems

Table 8-35 gives the stopping distance d(feet) of an automobile traveling at speed v (miles per fou) at the instant danger is sighted. (a) Graph d against v. (b) Fit a least-squares parabola of the form d = a + bv + cv^2 to the data. (c) Estimate d when v = 45 miles per hour and 80 miles per hour. (See attachment for table and o

Michigan Motors Corporation Goal Programming

Michigan Motors Corporation (MMC) has just introduced a new luxury touring sedan. As part of its promotional campaign, the marketing department has decided to send personalized invitations to test drive the new sedan to two target groups: 1) Current owners of an MMC Luxury car and 2) owners of luxury cars manufactured by one of