Devry MATH221 All Weeks LABs Latest 2019 JULY

MATH221 Statistics for Decision Making

Week 2 LAB

Creating Graphs

1. Create a pie chart for the variable Car Color: Select the column with the Car variable, including the title of Car Color. Click on Insert, and then Recommended Charts. It should show a clustered column and click OK. Once the chart is shown, right click on the chart (main area) and select Change Chart Type. Select Pie and OK. Click on the pie slices, right click Add Data Labels, and select Add Data Callouts. Add an appropriate title. Copy and paste the chart here.

2. Create a histogram for the variable Height. You need to create a frequency distribution for the data by hand. Use 5 classes, find the class width, and then create the classes. Once you have the classes, count how many data points fall within each class. It may be helpful to sort the data based on the Height variable first. Once you have the classes and the frequency counts, put those data into the table in the Freq Distribution worksheet of the Week 1 Excel file. Copy and paste the graph here.

3. Create a scatter plot with the variables of height and money. Copy the height variable from the data file and paste it into the x column in the Scatter Plot worksheet of the week 1 Excel file. Copy the money variable from the data file and paste it into the y column. Copy and paste the scatter plot below.

Calculating Descriptive Statistics

4. Calculate descriptive statistics for the variable Height by Gender. Sort the data by gender by clicking on Data and then Sort. Copy the heights of the males form the data file into the Descriptive Statistics worksheet of the week 1 Excel file. Type the standard deviations below. These are sample data. Then from the data file, copy and paste the female data into the Descriptive Statistics workbook and do the same

All answers should be complete sentences.

5. What is the most common color of car for students who participated in this survey? Explain how you arrived at your answer.

6. What is seen in the histogram created for the heights of students in this class (include the shape)? Explain your answer.

7. What is seen in the scatter plot for the height and money variables? Explain your answer.

8. Compare the mean for the heights of males and the mean for the heights of females in these data. Compare the values and explain what can be concluded based on the numbers.

9. Compare the standard deviation for the heights of males and the standard deviation for the heights of females in the class. Compare the values and explain what can be concluded based on the numbers.

10. Using the empirical rule, 95% of female heights should be between what two values? Either show work or explain how your answer was calculated.

11. Using the empirical rule, 68% of male heights should be between what two values? Either show work or explain how your answer was calculated.

MATH221 Statistics for Decision Making

Week 4 LAB

Calculating Binomial Probabilities

NOTE: For question 1, you will be using the same data file your instructor gave you for the Week 2 Lab.

1.Using the data file from your instructor (same one you used for the Week 2 Lab), calculate descriptive statistics for the variable (Coin) where each of the thirty-five students in the sample flipped a coin 10 times. Round your answers to three decimal places and type the mean and the standard deviation in the grey area below.

Plotting the Binomial Probabilities

? For the next part of the lab, open the Week 3 Excel worksheet. This will be used for the next few questions, rather than the data file used for the first question.

1. Click on the “binomial tables” workbook

2.Type in n=10 and p=0.5; this simulates ten flips of a coin where x is counting the number of heads that occur throughout the ten flips

3.Create a scatter plot, either directly in this spreadsheet (if you are comfortable with those steps), or by using the Week 1 spreadsheet and copying the data from here onto that sheet (x would be the x variable, and P(X=x) would be the y variable.

4. Repeat steps 2 and 3 with n=10 and p=0.25

5. Repeat steps 2 and 3 with n=10 and p=0.75

6. In the end, you will have three scatter plots for the first question below.

2. Create scatter plots for the binomial distribution when p=0.50, p=0.25, and p=0.75 (see directions above). Paste the three scatter plots in the grey area below.

Calculating Descriptive Statistics

Short Answer Writing Assignment – Both the calculated binomial probabilities and the descriptive statistics from the class database will be used to answer the following questions. Round all numeric answers to three decimal places.

3.List the probability value for each possibility in the binomial experiment calculated at the beginning of this lab, which was calculated with the probability of a success being ½. (Complete sentences not necessary; round your answers to three decimal places.)

P(x=0) P(x=6)

P(x=1) P(x=7)

P(x=2) P(x=8)

P(x=3) P(x=9)

P(x=4) P(x=10)

P(x=5)

4.Give the probability for the following based on the calculations in question 3 above, with the probability of a success being ½. (Complete sentences not necessary; round your answers to three decimal places.)

5.Calculate (by hand) the mean and standard deviation for the binomial distribution with the probability of a success being ½ and n = 10. Either show your work or explain how your answer was calculated. Use these formulas to do the hand calculations: Mean = np, Standard Deviation =

6.Calculate (by hand) the mean and standard deviation for the binomial distribution with the probability of a success being ¼ and n = 10. Write a comparison of these statistics to those from question 5 in a short paragraph of several complete sentences. Use these formulas to do the hand calculations: Mean = np, Standard Deviation =

7.Calculate (by hand) the mean and standard deviation for the binomial distribution with the probability of a success being ¾ and n = 10. Write a comparison of these statistics to those from question 6 in a short paragraph of several complete sentences. Use these formulas to do the hand calculations: Mean = np, Standard Deviation =

8.Using all four of the properties of a Binomial experiment (see page 201 in the textbook) explain in a short paragraph of several complete sentences why the Coin variable from the class survey represents a binomial distribution from a binomial experiment.

9.Compare the mean and standard deviation for the Coin variable (question 1) with those of the mean and standard deviation for the binomial distribution that was calculated by hand in question 5. Explain how they are related in a short paragraph of several complete sentences.

MATH221 Statistics for Decision Making

Week 6 LAB

Scenario/Summary

Click to download the Week 6 Lab Document (Links to an external site.) to complete the lab for this week. All of the directions are included in the document.

The data for this lab is distributed by your professor.

The document includes places where you need to input the answers. Any place where you see a gray box is where you need to put an answer.

Deliverables

Each student will submit a lab. Below is the grading rubric for this assignment.

Category Points % Description

Questions 1-5 8 points each, 40 total 50% large and small sample confidence intervals for a mean

Question 6 16 points 20% normal probabilities compared with data outcomes

Question 7 24 points 30% normal probabilities compared with data outcomes

Total 80 points 100% A quality lab will meet or exceed all of the above requirements.

Required Software

Microsoft Office: Word and Excel

Use a personal copy or access the software at https://lab.devry.edu (Links to an external site.).

Lab Steps

Prepare and Submit Lab

Open Excel.

Open the lab Word document.

Follow the steps in the lab Word document to do calculations in Excel.

Copy and paste from Excel into the Word document or retype the answer, and then complete the answers to the questions in complete sentences (fill in each gray box in the Word document).

Save the lab Word document, and submit it; no other files should be submitted

Statistical Concepts:

· Data Simulation

· Confidence Intervals

· Normal Probabilities

Short Answer Writing Assignment

All answers should be complete sentences.

We need to find the confidence interval for the SLEEP variable. To do this, we need to find the mean and standard deviation with the Week 1 spreadsheet. Then we can the Week 5 spreadsheet to find the confidence interval.

First, find the mean and standard deviation by copying the SLEEP variable and pasting it into the Week 1 spreadsheet. Write down the mean and the sample standard deviation as well as the count. Open the Week 5 spreadsheet and type in the values needed in the green cells at the top. The confidence interval is shown in the yellow cells as the lower limit and the upper limit.

1. Give and interpret the 95% confidence interval for the hours of sleep a student gets.

Change the confidence level to 99% to find the 99% confidence interval for the SLEEP variable.

2. Give and interpret the 99% confidence interval for the hours of sleep a student gets.

3. Compare the 95% and 99% confidence intervals for the hours of sleep a student gets. Explain the difference between these intervals and why this difference occurs.

In the Week 2 Lab, you found the mean and the standard deviation for the HEIGHT variable for both males and females. Use those values for follow these directions to calculate the numbers again.

(From Week 2 Lab: Calculate descriptive statistics for the variable Height by Gender. Click on Insert and then Pivot Table. Click in the top box and select all the data (including labels) from Height through Gender. Also click on “new worksheet” and then OK. On the right of the new sheet, click on Height and Gender, making sure that Gender is in the Rows box and Height is in the Values box. Click on the down arrow next to Height in the Values box and select Value Field Settings. In the pop up box, click Averagethen OK. Write these down. Then click on the down arrow next to Height in the Values box again and select Value Field Settings. In the pop up box, click on StdDevthen OK. Write these values down.)

You will also need the number of males and the number of females in the dataset. You can either use the same pivot table created above by selecting Count in the Value Field Settings, or you can actually count in the dataset.

Then use the Week 5 spreadsheet to calculate the following confidence intervals. The male confidence interval would be one calculation in the spreadsheet and the females would be a second calculation.

4. Give and interpret the 95% confidence intervals for males and females on the HEIGHT variable. Which is wider and why?

5. Give and interpret the 99% confidence intervals for males and females on the HEIGHT variable. Which is wider and why?

6. Find the mean and standard deviation of the DRIVE variable by copying that variable into the Week 1 spreadsheet. Use the Week 4 spreadsheet to determine the percentage of data points from that data set that we would expect to be less than 40. To find the actual percentage in the dataset, sort the DRIVE variable and count how many of the data points are less than 40 out of the total 35 data points. That is the actual percentage. How does this compare with your prediction?

7. What percentage of data would you predict would be between 40 and 70 and what percentage would you predict would be more than 70 miles? Use the Week 4 spreadsheet again to find the percentage of the data set we expect to have values between 40 and 70 as well as for more than 70. Now determine the percentage of data points in the dataset that fall within this range, using same strategy as above for counting data points in the data set. How do each of these compare with your prediction and why is there a difference?