Question

PROPERTY DATA
REID #	Address	Total Value	Heated Area	AC	FP
149128	6212 RIVER LANDINGS DR	$147,760.00	1362	Yes	Yes
33634	1429 KERSHAW DR	$503,928.00	3503	Yes	Yes
2552	2704 KNOWLES ST	$97,349.00	752	Yes	No
195111	100 DOVERSHIRE CT	$346,265.00	2348	Yes	Yes
182380	1209 TROTTER BLUFFS DR	$196,455.00	1770	Yes	Yes
223331	1809 BETRY PL	$205,512.00	1702	Yes	Yes
161966	215 TORREY PINES DR	$1,252,725.00	5482	Yes	Yes
162092	104 KEITHWOOD LN	$225,073.00	1678	Yes	Yes
147353	102 CULCROSS CT	$236,650.00	1984	Yes	Yes
146269	603 BROAD LEAF CIR	$114,830.00	1388	Yes	Yes
295713	2524 HIDDEN MEADOW DR	$265,743.00	2862	Yes	Yes
89006	109 KIERNAN CHOICE	$320,351.00	2634	Yes	Yes
219274	1706 ASHBARK CT	$238,192.00	2030	Yes	Yes
218914	8301 HOBHOUSE CIRCLE	$231,391.00	2074	Yes	Yes
164011	105 TOLLIVER CT	$337,743.00	3079	Yes	Yes
250499	363 SEASTONE ST	$237,908.00	2371	Yes	Yes
194739	106 LARSKSPUR LN	$295,116.00	1873	Yes	Yes
134186	7904 SUTTERTON CT	$355,379.00	2428	Yes	Yes
136262	1009 HARVEST MILL CT	$189,806.00	2068	Yes	Yes
126983	2013 COUNTRYWOOD NORTH RD	$411,819.00	2868	Yes	Yes
82591	500 PERRY CURTIS RD	$36,687.00	952	No	No
210521	113 DEEP GAP RUN	$301,433.00	2752	Yes	Yes
7805	906 DOROTHEA DR	$361,359.00	1344	Yes	No
50471	1209 PARK DR	$662,800.00	3080	Yes	Yes
205640	509 MIDENHALL WAY	$509,432.00	3045	Yes	Yes
152122	4501 FORTINGALE CIR	$256,712.00	1773	Yes	Yes
204944	" 5821 WILD ORCHID TRL	"	$435,881.00	3349	Yes	Yes
73613	"2760 KNOWLES ST	"	$103,089	1012	Yes	No

A. 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 are not 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. Show your work in doing these calculations, showing which formula you are using, giving the critical value, standard error, margin of error, etc...

B. . Explain what each of 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.

C. By increasing the confidence level, explain how the confidence intervals were affected and why that makes sense

D.  If more data was used in the sample, explain how the confidence intervals would be affected and why that makes sense.

E. Write a short report that summarizes what you discovered about the single family homes in Wake County

Answer 1

Put the data in excel and find the following values.

95% and 99% - Confidence interval for Total Value

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95% and 99% - Confidence interval for Heated Area

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95% and 99% - Confidence interval for AC

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95% and 99% - Confidence interval for FP

B. . Explain what each of 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.

We are 95% confident that the value of all homes in Wake county lies in the interval of (228064.54,406034.5906)

We are 99% confident that the value of all homes in Wake county lies in the interval of (196888.92,437210.21)

We are 95% confident that the Heated area of all homes in Wake county lies in the interval of (1892.11, 2648.09)

We are 99% confident that the Heated area of all homes in Wake county lies in the interval of (1759.68,2780.52)

We are 95% confident that the proportion of all homes with AC in Wake county lies in the interval of (0.89,1)

We are 99% confidenct that the proportion of all homes with AC in Wake county lies in the interval of (0.86,1)

We are 95% confident that the proportion of all homes with FP in Wake county lies in the interval of (0.72,0.99)

We are 99% confidenct that the proportion of all homes with FP in Wake county lies in the interval of (0.67,1)

C. By increasing the confidence level, explain how the confidence intervals were affected and why that makes sense

With increase in the confidence level the, interval becomes bigger because the tstat increase.

D. If more data was used in the sample, explain how the confidence intervals would be affected and why that makes sense.

With increase in the sample size n increase, hence the Margin of error decrease and also the interval becomes smaller.