Share
Explore BrainMass

Quantative Analysis of Data

Standard Deviation and Moving Averages

Standard deviation calculations similar to what is described in the following link. Chart number 2 and 3 reflect the following: The key numbers to focus on are the columns titled 'STDEV from 50 Day and STDEV from 200 Day'. The figures show how many standard deviations various stock market indices are above the moving ave

Statistics: Modify a formula, standard deviation, group designs, critical value

Clarifying the Steps - Chapter 9 9.2. Why do we modify the formula for calculating standard deviation when using t tests (and divide by N - 1)? 9.4. Explain why the standard error for the distribution of sample means is smaller than the standard deviation of sample scores. 9.8. Distinguish between within-group designs

Sample Range, Variance, and SD for the Data Series

Sample Data Description. United Package Service, Inc., delivers small parcels to business addresses in the Greater Detroit area. To learn more about the demand for its service, UPS has collected the following data on the number of deliveries per week for a sample of six customers: 3 4 5 6 2 4 A. Calculate the mean,

Mean, Standard Deviation, Approximate Value, Percentile Rank

See the attached files. Also, please see the formula sheet and standard normal distribution table to be used. Only use a scientific or graphing calculator (Excel does not help me) and please show all working out. Question 1 The following data set represents the oxygen uptake values for a random sample of 12 middle ag

Finding Marginal Distribution, Mean and Covariance of X and Y

Use the following function to answer the following questions: f(x,y) = (2(x + 2y)) / 3 0 <= x <= 1 , 0 <= y <= 1 0 elsewhere a) Find the marginal distribution of X. b) Find the marginal distribution of Y c) Find the mean of X d) Find the mean of Y e) Fin

Estimating Average Amount of Family Spending

Text book - "Data Analysis & Decision Making with Microsoft® Excel, Rev 3e, S. Christian Albright, Wayne L.Winston, Christopher J. Zappe" Chapter 9, Question 34 You are trying to estimate the average amount a family spends on food during a year. In the past the standard deviation of the amount a family has spent on food

Find the mean, variance and standard deviation

Could you please provide a step by step answer to the following question. Given the following frequency distribution, find the mean, variance, and standard deviation. Errors Frequency 36-38 18 39-41 7

About two-thirds of US households purchase ground coffee: What is the cost?

See attached file. In recent years, about two-thirds of US house holds purchased ground coffee. Consider the annual ground coffee expenditures for households purchasing ground coffee. Assuming that these expenditures are approximately distributed as a normal random variable with a mean of $65.16 and a standard deviation of $

Simple random sample of weights of women

7-9. Use the simple random sample of weights of women from a data set, we obtain these sample statistics: N= 35 X = 141.38 lbs Research from other sources suggest that the population of weights of women has a standard deviation given by o = 31.95 lb. a. Find the best point estimate of the mean weight of all women. (The

Statistics: Test freshmen and juniors for stressful events

Reasearchers were interested in examining the number of stressful events experienced by college students. They collected data from 2 groups of students: freshmen and juniors. The instrument they used to collect the data was a simple checklist that asked the student to check every item that that has occurred to you in the last th

Calculating the Average Availability of a System

Question: A system has a constant failure rate lambda = 0.0002 failures/hour. When an item fails, it is repaired to be as good as new condition. The associated mean downtime is 6 hours. The system is supposed to be in continuous operation. a) Find the Aav average availability of the system. b) How many hours per year will

Statistical Analysis: Graphical Representation of Data and Report

Federal Aviation Administration In January 2003, the FAA ordered that passengers be weighed before boarding 10-19 seat passenger airplanes. The order was instituted in response to a crash that occurred on January 8, 2003 in Charlotte, North Carolina, in which all 21 passengers, including the pilot and co-pilot, of a 19-seat

Statistics 8 questions

1. What is the relationship between the value for degrees of freedom and the shape of the t distribution? What happens to the critical value of t for a particular alpha level when df increases in value 2. The following sample was obtained from a population with unknown parameters Scores: 8, 0, 8, 8 a. Compute the sample me

Prof. Hardtack gave four Friday quizzes: Statistically assess the scores

Individual Assignment: Exercises From the E-Text ? Resource: Applied Statistics in Business and Economics ? Prepare answers to the following exercises from Applied Statistics in Business and Economics: ? Chapter 4: Exercises 4.4 Page 125; with modifications. The following problem is similar to exercise 4

Six Sigma Analysis: Tolerance Limits and Cpk

Suppose one of the key dimensions of U-bolts manufactured for a particular customer is 10.75 +/- 0.25. To qualify the process, you built 120 u-bolts and obtained the following data. Statistic U-Bolt Measurement Mean 10.717 Standard Error 0.00793 Median 10.7 Mode 10.65 Standard Deviation 0.0868 Sample Variance 0.007

Mean, median, mode, range and standard deviation of sample data

1. Calculate the (A) mean, (b) median (c) mode and (d) Range and (e) Standard Deviation for the data below. You may use full functions of Excel. Hint. Copy and paste the data into an Excel spread sheet. Copy, then click one cell in Excel, and paste. Excel will fill the proper cells below the one you selected. Mean______;

Random & Discrete Variable/ Continuous Probability Distributions

See attached files. See attached Practice Business Statistics for Management and Economics ch 7 & 8. The answers are highlighted in yellow. I have difficulty setting up the steps in Excel to come up with the correct answers. I need to see how the answers are derived in Excel. I have found the data required for problems

Measures of Central Tendency and Variation and their Interpretation

A quality characteristic of interest for a tea-bag-filling process is the weight of the tea in the individual bags. If the bags are under filled, two problems arise. First, customers may not be able to brew the tea to be as strong as they wish. Second, the company may be in violation of the truth-in-labeling laws. In this ex

Measures of Central Tendency and Standard Deviation

A. Calculate all measures of central tendency for data that are interval or ratio in measurement b. Calculate the standard deviation for data that are interval or ratio in measurement c. Assume this is a sample of students, calculate a t-test that compares boys and girls on the number of absences (you can assume equal vari

Statistical calculations to determine if to fire salesperson

A salesperson in a small appliance store sells the following number of air conditioners each month (starting in January) throughout the year. 3, 5, 5, 6, 12, 17, 14, 9, 4, 2, 1, 1. The store owner did a few calculations using one of his statistics books and concluded the salesperson should be fired. Using the knowledge you have

Normal Distribution, Mean, Median, Mode, Middle

1. Describe the properties of a normal distribution. Why are there infinite possible normal distributions? Why should one assume that sample data represents a population distribution? 2. Does all statistical data have a mean, median, or mode? Why? When is the mean the best measure of central tendency? When is the median the b

Unemployment Study

Case Problem #2 Unemployment Study See this link for the general problem. Make sure to use the attached data set, not the one in the book. http://books.google.com/books?id=_sOSAXTuy8cC&lpg=PA386&ots=24jaKDjmjL&dq=case%20problem%202%20Unemployment%20Study&pg=PA386#v=onepage&q=case%20problem%202%20Unemployment%20Study&f=fal

Descriptive statistics & Confidence Interval: Oil spill

Please see attached file for data. Owing to several major ocean oil spills by tank vessels, Congress passed the 1999 Oil Pollution Act, which requires all tankers to be designed with thicker hulls. Further improvements in the structural design of a tank vessel have been proposed since then, each of which the objective of redu