Share
Explore BrainMass

Descriptive Statistics

When the Mode is Better Than the Mean

1) When is "mode" the better measure? Think about what you have learned and how you can relate it to your profession, your daily life, or a realistic hypothetical situation. 2) Then, create (invent) a realistic small dataset that can be best described by mode and poorly described by mean. 3) List the dataset. 4)

Descriptive Statistics - Financial

• Warren Buffett is the Chairman and CEO of Berkshire Hathaway. Even though the firm has approximately 200,000 employees, Mr. Buffett has a staff of under twenty at the Omaha corporate headquarters. Do you believe that more companies should be run in this matter? Why or why not? • Additionally, Warren Buffett typically do

Forecasting

Time Period Actual Number of Units Sold 1 33 2 36 3 32 4 35 5 33 6 36 7 34 8 38 9 37 10 36 11 38 12 38 13 37 14 39 15 35 16 38 17 37 18 39 19 37 20 35 21 37 22 34 23 35 24 36 1. Based upon using mean absolute deviation (MAD) as a measure of forecast accuracy, which of the forecast models would be the p

Conducting simple regression and interpretating the results

//See attached for formatted version// 1.The marketing manager of a large supermarket chain would like to use shelf space to predict the sales of pet food. A random sample of 12 equalized stores is selected, with the following results. Store Shelf Space(X) Weekly sales(Y) 1 5 160 2 5 220 3 5 140 4 10 190 5 10 240 6 1

Height of Students - Distributions & Deviations Report

20 students' heights were measured for statistic analysis, with the following results: female 5'6, female 5'8, male 5'9, male 5'6, female 5'7, female 5'5, female 5'6, male 5'10, male 5'8, female 5'4, female 5'4, male 5'9, female 5'1, female 5'5, male 5'11, male 5'7, female 5'6, female 5'8, male 6'1. male 5'9 Please return

Confidence Interval & Sample Size Calculated Step by Step

1. If X bar = 85, σ = 8, and n = 64, construct a 95% confidence interval estimate for the population mean, µ. Show work! That is draw the a) normal curve, b) put in the given information(mean and standard deviation), c) identify the area to be solved, d) show the Z conversion of the X values, e) use the Standardized normal T

Discuss Validity of Central Limit Theorem

What is the Central Limit Theorem? How large should the sample size be if the underlying distribution of the population values are: a. Normally distributed (discuss). b. Non-normally distributed. (discuss) 2. What is the difference, if any, between the standard deviation of the sample and the standard error of the mean

Statistics: measures of central tendency

Table 1 An insurance company evaluates many numerical variables about a person before deciding on an appropriate rate for automobile insurance. A representative from a local insurance agency selected a random sample of insured drivers and recorded, X, the number of claims each made in the last 3 years with the following results

statistical observation

A. Select a topic of interest - preferably College related such the height of students or the number of hours they take to prepare for classes. B. Choose 2 variables to observe: 1) Female and 2) Male C. Collect 20 data points on each variable 1. Perhaps, you may design a questionnaire to collect you data 2. The design of you

MANOVA in Drug Selection

In this exercise, you are playing the role of a researcher that is testing new medication designed to improve cholesterol levels. When examining cholesterol in clinical settings, we look at two numbers: low-density lipoprotein (LDL) and high-density lipoprotein (HDL). You may have heard these called "good" (HDL) and "bad" (LDL)

Dependent Sample T-test

In this activity, we are interested in finding out whether participation in a creative writing course results in increased scores of a creativity assessment. For this part of the activity, you will be using the data file "Activity 4a.sav". In this file, "Participant" is the numeric student identifier, "CreativityPre" contains cr

Library of Congress

The head librarian at the Library of Congress has asked her assistant for an interval estimate of the mean number of books checked out each day. The assistant provides the following interval estimate: from 740 to 920 books per day. If the head librarian knows that the population standard deviation is 150 books checked out per da

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

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

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

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

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