**BUS 310 Homework 1**

**Please download the Homework 1 Excel file. This file contains all the data required to complete the assignment. Please follow the directions in the textbook, as well as the specific steps contained in this document. You are required to use StatTools to solve most of these problems. Please note change the default setting in StatTools > Utilities > Application Settings > Reports > Placement to “Active Workbook”**

**Problem 1 Page 290:**

Please complete all three parts included in the problem. Use StatTools to complete Part B and Part

- Remember you must create a data set using the Data Set Manager. Leave out column A. Only select the
**Annual Salary**variable for output. You can make a new data of the random sample output to calculate of the metrics. For Part C, please the calculations on the main problem worksheet. Make sure that all your worksheets containing output, specifically StatTools are all adjacent and in order. Is the population mean included in the confidence interval? Please answer on StatTools output page.

**Problem 5 Page 291:**

Please complete **Part A only**. The problem worksheet is already setup to complete this problem. The most difficult issue with this problem is building the formula to count the specific intervals of random numbers. Here is the first formula for counting the range 0 to .10 :

**=COUNTIF($B$2:$B$1001,”<=.1″) **. The big hint here is that for each next interval, say for .2

- you must subtract
**all**the previous intervals… so that you are left with just the count for the specific interval. This is a little difficult, tedious and messy. One you have all the correct counts, they will all be approximately the same value +-, create a neat histogram. Make the chart larger, add a title and all axis labels. Click the “bars”, then right click and choose**Add Data Label**. Now press**function key F9**to recalculate a few times.

**Problem 14 Page 307:**

This problem is fairly long and intricate. The goal is to review the concepts relating to the sampling distribution of the mean and the calculation of the stand error of the estimate. You will calculate or add input to all the “gray” areas.

Calculate the population mean of the “Heights” and place in **A10**.

Calculate the population standard deviation and place in **A13**.

Calculate the standard error of the sample mean and place in **A6**.

Note that columns **D** to **F** contain every possible sample, of size 3, of people from the population data contained in **A3:B7**. This is a very small example, thus an exhaustive list of all samples of a

specific sample size could be generated. This becomes exponentially difficult as the number of observations in the population increase… until it becomes untenable.

Using the **=VLOOLUP** function, place the heights of each population member contained the sample in columns G to I. Hint: cells G3 to H3 all contain the height of 67.

Calculate the mean of the sampling distribution and place the formula in **L3**, using the means calculated for each row sample from column **J**.

Calculate the population standard deviations of the samples means contained in column **J** and place the formula in **L6**.

Create a professional looking histogram of the sample means in column J. Make sure to increase the size, add title, and axis labels and add data labels. Place the chart to the right of the data section.

What do you notice about the standard error and the population standard deviation calculations of the sample means?

**Problem 5 page 323**:

Sort the data set on **Year** from “Highest to Lowest.”

Calculate the “population” mean of **Total Salary** for just 2009. Place formula in **G1**.

Use StatTools to complete the remainder of the problem.

Create a data set for **only** 2009 observations. Name the data set Problem 5 Page 323.

Create a random sample of the 2009 data set.

Create a new data set containing the random samples just generated.

Name the data set Random (2).

Create a confidence 95% confidence interval using the Random (2) data set.

Make sure to move the new worksheet adjacent to the Random (2) worksheet.

On the Confidence Interval work sheet, answer the question: Does the confidence interval contain the population mean contained P 5 Page 323 worksheet?

**Problem 15 Page 331:**

Please complete this problem using StatTools.