Graduate_Student

QRB-501 University of Phoenix Week-5 assignment template Please follow the instructions carefully: 1. Fill out your name 2. For each question, please show the answers only. I suggest that you do your calculations in Excel and transcribe your answers on this template 3. Please do not change the template in any way; if you need extra space to answer your question, use the enter key to have extra space in the appropriate cell Student’s Name: Nancy Villarosa Text: Sevilla & Somers Activity 17.1 In the first part of this activity, you will generate some data that should have an approximately normal (or bell-shaped) distribution. In the second part, you will use the definition of standard deviation and compare the standard deviations for two different data sets. Work with a partner to generate the following data. Toss 10 coins and record the number of heads you obtained. Repeat this 24 more times until you have a list of 25 numbers, each of them between 0 and 10. Organize the data set from b) the results of 24 tosses of 10 coins in a Excel file so that, the column B contains the number of times 0 heads was obtained in the 24 tosses of 10 coins, the column C contains the number of times 1 head was obtained in the 24 tosses, and so on, up to the number of times 10 heads was obtained. Answer: Create a scatter plot of these data, using one of the versions of the scatter plot with the dots connected. Describe what your curve looks like, including where it is “centered” and what its “spread” is. Please use cut and paste comment to place just the plot below. Make sure that your plot does not exceed the margin of the table. Your description should be below the plot in this box. The center of the distribution appears to be on 5. The distribution is very symmetric with almost none of the results being extreme tails of the distribution. There were no 9’s, 10’s, or 0’s and only one 1, one 2, and one 8. Besides these extremes values, the data varies throughout the range, although most of the distribution is in the center of the data. There is a bell curve shape. The spread is 7. Change your graph to a bar graph (See instruction in the text). Please use cut and paste comment to place just the plot below. Make sure that your plot does not exceed the margin of the table. Your description should be below the plot in this box. The bar graph (histogram) shows how many times a toss of ten coins will produce a certain number of heads. 5 heads showed up 7 times in a 25 toss; 3,4, and 6 showed up heads 4 times, 7 heads showed up 3 times, and 1, 2, and 8 heads showed up only one time. Topic 17 Exploration 2 Answer: The tables (see the text Page 303-304) provide information about the top women-owned businesses in the U.S. The first table gives year 2000 revenue in millions of dollars and number of employees for Pennsylvania women-owned companies with year 2000 revenues of $70 million or higher. The second table gives the same information for Michigan women-owned companies with year 2000 revenues of $70 million or higher. (see the text Page 303-304) a) Use a calculator or computer to compute the mean and standard deviation of the year 2000 revenue for the Pennsylvania companies in the first table. b) Use a calculator or computer to compute the mean and standard deviation of the year 2000 revenue for the Michigan companies in the second table. c) How would the mean and standard deviations change if the largest data value in each set were removed' d) Find the mean and the standard deviation of the number of employees for the Pennsylvania companies in the first table. e) Find the mean and the standard deviation of the number of employees for the Michigan companies in the second table and compare to your results in part d of this exploration. You only need to transcribe the means and standard deviations in the following table Mean Standard deviation a) $631.25 million $741.68 million SAMPLE SD $693.78 million POPULATION SD b) $210.17 million $195.70 million SAMPLE SD $189.06 million POPULATION SD c) TABLE 1 $435.71 million PA TABLE 2 $168.04 million MI The mean and the Standard Deviation decreased on PA TABLE 1 and on MI TABLE 2 as well. TABLE 1 $533.78 million PA SAMPLE SD $494.18 million PA POPULATION SD TABLE 2 $112.12 million MI SAMPLE SD $108.04 million MI POPULATION SD d) 2974 3979 SAMPLE SD 3721.90 POPULATION SD e) 740 941 SAMPLE SD 909.10 POPULATION SD e) Continuation – The average number of employees in Pennsylvania companies is much higher (almost 4 times) than of the Michigan companies. It appears that Pennsylvania companies have enrolled more labor compared to their Michigan counterparts. However, the average spread in the number of employees higher (almost 4 times) across the Pennsylvania companies than across the Michigan companies, which could mean that some companies across Pennsylvania have enrolled labor more heavily than the others, as compared that across Michigan companies. Text: Lind, Marchal, & Wathen text Chapter 2: Ex: 11 (a, & c) The following frequency distribution reports the number of frequent flier miles, reported in thousands, for employees of Brumley Statistical Consulting, Inc. during the first quarter of 2004. a. How many employees were studied' c. Construct a histogram. Answer: a. 50 Employees c. Chapter 3: Ex-85 Refer to the CIA data (see the text) , which reports demographic and economic information on 46 countries. a. Select the variable Life Expectancy. 1. Find the mean, median, and the standard deviation. 2. Write a brief summary of the distribution of life expectancy. b. Select the variable GDP/cap. 1. Find the mean, median, and the standard deviation. 2. Write a brief summary of the distribution GDP/cap. Answer: a 1. Mean = 73.81, Median = 76.105 Standard Deviation = 6.90 (SAMPLE STANDARD DEVIATION) Standard Deviation = 6.83 (POPULATION STANDARD DEVIATION) 2. Life expectancy is skewed to the left. That is most of the data is located on the right side of the distribution with a few low extreme values. This can also be seen in noting that the mean is somewhat lower than the median. Because the mean is affected by outliers, we expect it to be pulled toward extreme values. Life expectancy from the countries included in the data is mostly amongst 75 to 80 according to the frequencies calculated from the data given.