Question

Consider a population consisting of the following five values, which represent the number of DVD rentals during the academic year for each of five housemates: 14 16 10 11 a. Compute the mean of this population. [5 pt b. Select a random sample of size 2 by writing the five numbers in this population on slips of paper, mixing them, and then selecting two. Compute the mean of your sample. [5 pt c. Repeatedly select samples of size 2, and compute the value for each sample until you have the values for 25 samples. [5 pt e. [New] Compare the population mean with the mean of the 25 sample mean values. Discuss their similarity or difference. [5 pt

Answer 1

a) (8+14+16+10+11) / 5 = 11.8

b) Let random sample of size 2 = 16,10

Mean = (16+10)/2 = 13

c) 25 samples:

Sample	Mean
8,8	8
8,14	11
8,16	12
8,10	9
8,11	9.5
14,8	11
14,14	14
14,16	15
14,10	12
14,11	12.5
16,8	12
16,16	16
16,10	13
16,11	13.5
10,8	9
10,14	12
16,14	15
10,16	13
10,10	10
10,11	10.5
11,8	9.5
11,14	12.5
11,16	13.5
11,10	10.5
11,11	11

e)

Population mean = 11.8

And the mean of 25 samples in c) are mostly near 11.8.

So Most of the (Xbar) values are near population mean.

X bar values differ a lot from sample to sample.