Overview:To better understand statistical inference you will use sampling techniques and confidence intervals to answer questions concerning a population of single-family homes in Wake County, North Carolina. Rather than going from house to house in the county, you will make use of an online database that lists key characteristics of these homes.

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Before you start working on this activity, click on the link below to save a copy of theData Report FormExcel file to your computer. You'll need this form to record the information from the property listing and to do your data analysis. You can also put the answers to the questions below on the same Excel form.As a reminder, you canget Excel for freeand enter your school email address. You may have to leave the "my." out of your email.

Click on the Link:Real Estate Starter Data

There are approximately 310,000 properties in the Wake County database. In the file linked above, there are 50 "random" numbers generated for you to use. In this activity, you need a sample of 30 single-family homes. There are 50 random numbers becausesome of the real estate properties won't be single-family residences. You can stop once you have 30 single-family homes. The first 25 single-family homes are completed for you, so you only need to find 5 more.

1. Open the websiteWake County Real Estate Data. The website allows the user to search property listings based on their Real Estate Id (REID) number as well as other indicators. You will entereach ID numberfrom your list of randomly generated numbers until you have a total of 30 single-family houses.
3. After you enter the REID number, you will be transferred to an account summary for the property listing. Click on theBuildings tab.
5. Before going any further,verify the property is a single family home. If the property is not a single family home, enter the next randomly generated number in the Account Search field to the right. Do not enter data from properties that are not listed as single family homes.
7. If the property is a single family home, record the following in the Excel fileyou had downloaded earlier:
9. Real Estate ID Number - Record the number
10. Address - Record the street address
11. Total Value assessed - Record the amount
12. Heated Area - Record the number
13. Air Conditioning - Record yes or no
14. Fireplace - Record yes or no
16. Calculate 95% and 99% confidence intervals for the Total Assessed Value, Heated Area, Air Conditioning, and Fireplaces based on your sample data. Keep in mind that these variables arenot the same type. You'll need to decide which formula to use for each variable. There should be a total of 8 confidence intervals calculated, 2 for each of the 4 variables.
18. Explain whateachof the confidence intervals tell you concerning the homes in Wake County. Write these explanations in full sentences!Example: We are 95% confident that the mean assessed value of all homes in Wake County is... etc.
20. Considering the confidence intervals, answer the following questions:
21. a.By increasing the confidence level,explainhow the confidence intervals were affected and why that makes sense.
22. b. If more data was used in the sample,explainhow the confidence intervals would be affected and why that makes sense.