Question

Situation: The Ipod Touch has been out for two years now and a lot of data has been collected.

Relevant Relationship:

There is a functional relationship between Price of an IPod Touch,pp and Weekly Demand,ss.

Below is a table of data that have been collected

Price,pp,($)	Weekly Demand,ss,(1,000s)
150	211
170	201
190	197
210	183
230	176
250	175

A.. Find the linear model that best fits this data using regression and enter the model below

(for entry round the linear parameter value to nearest 0.01 and constant parameter to nearest 1)

s=T(p)=s=T(p)=     syntax error

B. The squared correlation coefficient r2r2 was Select an answer below above  0.95

(note: values less than 0.95 MAY mean the model is not appropriate for making predictions)

Now answer these two questions using the UNROUNDED model parameters

C. What does the model predict will be the weekly demand if the price of an ipod touch is $40 ?  (nearest 100)

D. According to the model at what should the price be set in order to have a weekly demand of 183,600 ipod Touches? $(nearest $1)

Note: In the "real" world Apple sold about 20 million Ipod Touch's from Sept. 2007-Sept. 2009 Answer

My TI calc is broke, i have an app but it cant go through functions, so please layout full format and work and i can just substitute numbers in, thank you very much.

Answer 1

	Price	Demand	P^2	D^2	P*D
	150	211	22500	44521	31650
	170	201	28900	40401	34170
	190	197	36100	38809	37430
	210	183	44100	33489	38430
	230	176	52900	30976	40480
	250	175	62500	30625	43750
Sum	1200	1143	247000	218821	225910
Mean	200	190.5
N	6	6

A) Linear regression:

Y'=a+bX

B)

Hypothesis test:

and

Test statistic:

P-value: 0.001

The test statistic is significant and we conclude there is a significant relationship between variables.

c)

X=40

(1000's)

d)

If Y= 183600, then X=?

answered by: anonymous