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Descriptive Statistics


A list of 52 employees is below. 1) please compute the mean, median, and standard deviation of the list of the 52 employees. 2) Use excel to choose a simple random sample of size 15 from this frame. 3) please compute the mean, medium, and standard deviation of the annual salaris for the 15 employees included in the si

Quantitative Reasoning for Population Declines

A small town is in a population decline. The town manager has discovered that the town's population is decreasing exponentially at 6% annually. Based on this trend, the town population has decided that if the population falls to 1,000 or less, they cannot pay the town manager's salary. A) If the 2003 population is 12,345 peo

Confidence Intervals for the Mean

Confidence Intervals for the Mean (Large Samples) Find the critical value zc necessary to form a confidence interval at the given level of confidence. (References: definition for level of confidence a. 95%= b. 75%=

Annual Cost of Busing Students to School

The Springdale School board has made the decision to close one its junior high schools (seventh and eight grades) at the end of the school year and reassign all of next year's students to one of the three remaining junior high schools. The school district for the closed school has been divided into five areas as shown in the ta

Transportation and Model Formulation

5. In the transportation problem on the next page, products are produced at plants in Locations A and B and shipped to warehouses in locations X, Y and Z. 5a. According to the model formulation, what is the capacity of Plant B? _________ 5b. According to the model formulation, what is the demand at warehouse Z? ________

PERT network, earliest and latest start time

1. Draw the PERT network, identify the earliest and latest start time for each activity and the amount of slack for non-critical activities Completion Immediate Earliest Latest Amount Activity Time Predecessor Start Start

Population growth model for Austin, TX

In 1990, the population of Austin, Texas, was 494,290. During the next 10 years, the population increased by about 3% each year. A. Write a model (equation) showing the population, P, in thousands of Austin t years after 1990. B. What was the population in 2000? Show your work. C. Estimate the year when the population

Statistics Charts

As the production manager for an electronic circuit company you have encountered the following situation. Part 1 A process for producing electronic circuits has achieved very high yield levels. An average of only 10 defective parts per million is currently produced. What are the upper and lower control limits for a samp

Descriptive statistics and probability problems

Hello. I need help towards this one problem only. It tends to be confusing to me. Please can anybody help me? Determine whether a probability distribution is given. In those cases where a probability distribution is not described, identify the requirements that are not satisfied. In those cases where a probability distributio

Descriptive statistics

The monthly average low temperatures* during different months of year at Denver, CO are given below: January February March April May June 5 8 18 29 40 50 July August September October November December 55 53 44 32 24 12 Source: www.weather.com Word-process your solution and answers below. a) Find the mean year

Descriptive statistics

Below is some data from 2005 for on-the-job deaths in some dangerous jobs. Which job seems the most dangerous? Which seems the least dangerous? Explain. total deaths total employed Driver 993 3,412,370 Farmers 341

Statistics: Catagorical and Numerical Variables

1.22 The U.S. Census Bureau site, www.census.gov,contains survey information on people, business, geography, and other topics. Go to the site and click on Housing in the "People and Households" sections. Then click on American Housing Survey. a. Briefly describe the American Housing Survey. b. Give an example of a categor

Removing Outliers from Data

While exploring data that was collected for an investigation of resources needed for software testing and improvement, you have found an outlier. The study is focused on two variables: the number of bugs found in the code and the time (in person-hours) required to fix them. The outlier corresponds to a very large project with

Article Summary: Consumers and Their Memory of Smell

Consumers didn't need to be told that Jazz Diet Pepsi was about to hit store shelves; they could smell it. The soft-drink company had placed an ad laced with scents of black cherry and French vanilla in the October 2006 edition of People magazine. Four months later, British travel agency Thomson Holidays sprayed its store win

Tournament Rounds- Decay Rate

2. Each year the local country club sponsors a tennis tournament. Play starts with 128 participants. During each round, half of the players are eliminated. How many players remain after 5 rounds? At what round does the tournament can't be played anymore? Chart the decay rate.

Brownian Motion: Martingale Processes

Let W(t) be a Brownian motion. For each of the following processes, verify whether it is a martingale process: (1) X(t)=W^2(t)−t (2) X(t)=W^3(t)−3tW(t) (3) X(t)=t^2W(t)−2∫uW(u)du (The limit on the integral is 0 to t) (4) X(t)=W^2(t)

How many ads of each type should the candidate for mayor use

A candidate for mayor in a small town has allocated $40,000 for last minute advertising. He will be using two types of ads radio ads which cost $200 per ad and reach 3,000 people and television ads which cost $500 per ad and reach 7,000 people. In planning the campaign the manager would like to reach as many people as possible b

Finding Sampling Errors

There are 4 samples of 40 individuals each interviewed to find out how often they visit a fast food restaurant in the week. The averages of each sample were 2.5, 3.4, 2.3 and 3.0. If the average is 2.85 and its standard deviation is 50 and we assume that the population is normally distributed. a) Find the sampling error for e

Descriptive Statistics and hypothesis testing

1. Suppose that a broad cross section of high school students took a very difficult scholarship exam and almost all scored very low but a very small number scored very high. When plotted as a curve, the distribution will show what type of skew? 2. Which type of distribution is often found in the nature? 3. What is the form

Productivity and Variables

Many people attend work and produce little or nothing of value that is why they are terminated. attendance + work quality = productivity. Can you think of other variables that influence productivity

Descriptive Statistics and Probability calculations in Minitab.

Sect. 5-2, p. 209 Identifying Probability Distributions. In Exercise 7-12, determine whether a probability distribution is given. In those cases where a probability distribution is not described, identify the requirements that are not satisfied. In those cases where a probability distribution is described, find its mean and

Scale of Measurement

Identify the scale of measurement in each of the following: a. attitudes toward school b. grouping students on the basis of hair color c. asking judges to rank order students from most cooperative to least cooperative

Frequency Distribution

The following frequency distribution reports the electricity cost for a sample of 50 two bedroom apartments in Albuquerque, New Mexico during the month of May last year. a. Estimate the mean cost. b. Estimate the standard deviation. c. Use the Empirical Rule to estimate the proportion of costs within two standard deviations

Growth Rate of Computer Stocks

1. a. Computer stocks currently provide an expected rate of return of 16%. Dell, a large computer company, will pay a year-end dividend of $2 per share. If the stock is selling at $50 per share, what must be the market's expectation of the growth rate of Dell dividends? 1. b. If dividend growth forecasts for Dell are revised