In: Statistics and Probability
The assets (in billions of dollars) of the four wealthiest people in a particular country are 33, 30, 19, 12.
Assume that samples of size n=2 are randomly selected with replacement from this population of four values.
a. After identifying the 16 different possible samples and finding the mean of each sample, construct a table representing the sampling distribution of the sample mean. In the table, values of the sample mean that are the same have been combined.
Xbar |
Probability |
Xbar |
Probability |
|
---|---|---|---|---|
33 |
22.5 |
|||
31.5 |
21 |
|||
30 |
19 |
|||
26 |
15.5 |
|||
24.5 |
12 |
a)
below is sampling distribution of sample mean :
x1 | x2 | probabilityP(x1,x2) | x̅ | |
33 | 33 | 1/16 | 33 | |
33 | 30 | 1/16 | 31.5 | |
33 | 19 | 1/16 | 26 | |
33 | 12 | 1/16 | 22.5 | |
30 | 33 | 1/16 | 31.5 | |
30 | 30 | 1/16 | 30 | |
30 | 19 | 1/16 | 24.5 | |
30 | 12 | 1/16 | 21 | |
19 | 33 | 1/16 | 26 | |
19 | 30 | 1/16 | 24.5 | |
19 | 19 | 1/16 | 19 | |
19 | 12 | 1/16 | 15.5 | |
12 | 33 | 1/16 | 22.5 | |
12 | 30 | 1/16 | 21 | |
12 | 19 | 1/16 | 15.5 | |
12 | 12 | 1/16 | 12 |
sample | sample | |||
mean | probability | mean | probability | |
33 | 1/16 | 22.5 | 1/8 | |
31.5 | 1/8 | 21 | 1/8 | |
30 | 1/16 | 19 | 1/16 | |
26 | 1/8 | 15.5 | 1/8 | |
24.5 | 1/8 | 12 | 1/16 |