Download 1. As the sample size increases, the sampling distribuion of the

1. As the sample size increases,
the sampling distribuion of the mean becomes less predictable.
the sampling distribution of the mean becomes increasingly skewed.
the sampling distribution of the mean approaches a normal distribution.
the sampling distribution of the mean approaches the distribution of the population.
2. As the sample size increases, the standard deviation of the sampling distribution of the mean
(also called the standard error of the mean) will:
Increase
Decrease
First increase, then decrease
First decrease, then increase
3. IQ is normally distributed in the population with a mean of 100 and a standard deviation of 15.
For samples of 25 people, the mean of the sampling distribution of the mean is Blank 1
and the standard error of the mean is Blank 2
.
(Give numeric answers)
4. Low-density lipoprotein (LDL) is an important part of the blood cholesterol test. The mean
LDL for people 65 and older is 130 with a standard deviation of 12. The mean LDL for people
under 40 is 100 with a standard deviation of 12.
Consider the sampling distribution of the difference between means for these two populations
where the sample size is 8 for both groups. If the difference is found by subtracting the mean
LDL for the under 40 group from the mean LDL for the 65 and over group, then the mean of the
sampling distribution of the difference between means is Blank 1
error of the difference between means is Blank 2
(Answer with numbers, no words).
.
and the standard
5.
LDL(mg/dl)
65 and over Under 40
130
120
143
90
114
64
110
77
123
102
110
83
134
127
124
105
Low-density lipoprotein (LDL) is an important part of the blood cholesterol test. The mean LDL
for people 65 and older is 130 with a standard deviation of 12. The mean LDL for people under
40 is 100 with a standard deviation of 12. A health center had a free blood cholesterol test for all
people in the community. The blood test results for the people under 40 and 65 an over are given
in the attached excel file called "Cholesterol Data-2"
What is the probability that the mean LDL of 8 people who are 65 or over would exceed the
mean LDL of 8 people who are under 40 by the difference in these two samples of more?
(give your answer to at least 3 decimal places)
Consider the sampling distribution of the difference between means for these two populations
where the sample size is 8 for both groups. If the difference is found by subtracting the mean
LDL for the under 40 group from the mean LDL for the 65 and over group, then the mean of the
sampling distribution of the difference between means is Blank 1
error of the difference between means is Blank 2
and the standard
.
(Answer with numbers, no words).
6. Imagine the correlation between high school GPA and college GPA in a population was 0.37.
Imagine we randomly select 200 people and obtained the correlation of 0.34. What’s the standard
error of Z’ for N=200?
(Answers should be numeric. Give your answer to at least 3 decimal places)
7.
Height
(inches)
Running Speed
(seconds)
60
8
55
11
56
10
52
12
48
14
44
16
47
13
52
12
Data from a random sample of eight elementary school children. Each child was measured for
height (in inches) and timed in the 40-yard dash (in seconds).
(You may have to hit "Enable Editing" after opening the file)
What is z' for the correlation between height and speed in this sample?
(Give your answer to at least 3 decimal places)
8. Imagine, in a given community, 20% of people above 60 years old have heart disease. If we
randomly choose 10 people above 60 years old, EXACTLY how many of them will have heart
disease?
2
4
6
We cannot tell from the information given
9. Out of 3000 students in a School of Public Health, 1500 students defined themselves regular
dietary supplement users. What would be the mean of the sampling distribution of the proportion
of students who defined themselves as dietary supplement users in the school?
(Answer should be in the form of a decimal and it should be exact)
10. Out of 3000 students in a School of Public Health, 1500 students defined themselves regular
dietary supplement users. If you take a sample of 20 of them, what’s the standard error of the
proportion (p) of those who defined themselves as dietary supplement users in the school?
(Give your answer to at least 3 decimal places)