Question

3. The end-of-year report for last year indicated the average sell price for houses in Las Cruces is $190,000. A realtor wants to conduct an experiment to show that the house sell price has increased this year compared to last year. He randomly selected 35 houses that are sold this year, and the data is provided in the Excel file provided (1) Make a boxplot on the house sell price, and identify if there are outliers observed from the data. Attach the boxplot here. (refer to Unit 5) (2) Take out the outliers (simply delete the outlier data). There is no other information provided for the study, which hypothesis test will be appropriate to address the research question? (z test or t test) (3) Use Excel to conduct the hypothesis test. Attach the Excel output here, then write the 5-step procedure of the test below. (Don't forget to create the dummy variable before choosing the "t test: Two-Sample Assuming Unequal Variances") (4) Based on your conclusion of part (3), what type of error could you possibly make? (type I or Type II)

House Sell Price
187000
181000
184000
188000
196000
198000
500000
187000
188000
189000
201000
202000
202000
173000
194000
188000
199000
195000
183000
185000
180000
187000
213000
207000
207000
200000
200000
218000
189000
197000
208000
188000
212000
195000
185000

Answer 1

(1)

600000 500000 400000 Price 300000 200000 100000 0 1

Price 500000 is outlier as it falls beyond the limits of box plot.

(2) After removing oulier there are 34 observations left so we can use one sample t test to test the claim.

(3)