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Descriptive Statistics

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28) police response time to an emergency call is the difference between the time the call is first received by the dispatcher and the time a patrol car radios that it has arrived at the scene. Over a long period of time, it has been determined that the response time has a normal distribution with a mean of 8.4 minutes and a stan

Statistics: Testing Hypotheses

The attached file contains the yield for a money market account, a one-year certificate of deposit (CD), and a five-year CD for 23 banks. a) At the 0.05 level of significance, is there evidence of a difference in the mean yield of the different accounts? b) If appropriate, determine which accounts differ in mean yields. c)


A) SPSS and Data Summary: From the dataset attach, select any two quantitative variables. What is the name of your two quantitative variables you will be analyzing? Use SPSS to compute summary (descriptive) statistics, including measures of central tendency mean, median, mode and numerical measures variance and standard devia

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

Finding Critical Value for Z Using Excel Function

For each of the following situations, find the critical value for Z. a)    H0: P = 0.05 vs. HA: P > 0.05 at α = 0.05. b)   H0: P = 0.6 vs. HA: P ≠ 0.6 at α = 0.01. c)    H0: P = 0.5 vs. HA: P < 0.5 at α = 0.01; n = 500. d)   H0: P = 0.2 vs. HA: P < 0.2 at α = 0.01.


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

Correlation Coefficient for Absenteeism and Age

A personnel manager for a large corporation feels that there may be a relationship between absenteeism and age and would like to use the age of a worker to develop a model to predict the number of days absent during a calendar year. A random sample of 10 workers was selected with the results presented below: Age Da

Finding the Confidence Interval at 95% Confidence

A sample of 75 information system managers had an average hourly income of $40.75 with a standard deviation of $7.00. What is the 95% confidence interval for the average hourly wage of all information system managers?

Computing the slope of regression line for given data

The following information regarding a dependent variable Y and an independent variable X is provided S = SUM (SX means Sum of x values) SX = 90 S (Y - nar008-1.jpg)(X - nar008-2.jpg) = -156 SY = 340 S (X - nar008-3.jpg)2 = 234 n = 4 S (Y - nar008-4.jpg)2 = 1974 SSR = 104 The slope of the regression equation is

Application of Central Limit Theorem

Random samples of size 81 are taken from an infinite population whose mean and standard deviation are 200 and 18, respectively. The distribution of the population is unknown. The mean and the standard error of the mean are?

Finding the Slope of Regression Line

The following information regarding a dependent variable Y and an independent variable X is provided S = SUM (SX means Sum of x values) SX = 90 S (Y - nar008-1.jpg)(X - nar008-2.jpg) = -156 SY = 340 S (X - nar008-3.jpg)2 = 234 n = 4 S (Y - nar008-4.jpg)2 = 1974 SSR = 104 Find the slope of the regression equati

Calculating sample confidence interval for a population mean

Please see attachment for the data to be used when answering these questions. a. Develop a 95% confidence interval for the mean number of miles driven until transmission failure for the population of automobiles with transmission failure. Provide a managerial interpretation of the interval estimate. b. Discuss the implicat

Implication of Negative Correlation

Assuming a linear relationship between X and Y, if the coefficient of correlation (r) equals - 0.30, a. there is no correlation b. the slope (b1) is negative C. Variable X is larger than variable Y D. The variance of x is negative

Determining the Required Sample Size

An economist is interested in studying the incomes of consumers in a particular region. The population standard deviation is known to be $1,000. A random sample of 50 individuals resulted in an average income of $15,000. What sample size would the economist need to use for a 95% confidence interval if the width of the interval s

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

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