Access over 20 million homework & study documents

Written Midterm Review 2 2

Content type
User Generated
Subject
Statistics
School
University of Colorado Boulder
Type
Homework
Rating
Showing Page:
1/7
SOC 2061: midterm review Name:
_______________________________
Please be sure to show all your work on this exam, including any
formulas used, calculations conducted, and drawings used to arrive at
your answers!
1. The mean age at first marriage for respondents in a survey is 23.33, with
a standard deviation of 6.13
a. Calculate the Z score associated with an observed age at first marriage
of 25.50 and explain what the Z score tells you.
Answer
 





b. Calculate the observed age at first marriage associated with a Z score
of -0.72.
Answer
Given ,z-score of -0.72



 
c. What proportion of respondents were married for the first time between
the ages of 20 and 30?
Answer
P(20<X<30) = P( 




 


  
d. If an individual was married for the first time at the age of 35, what
percentile is he or she in?
Answer

Sign up to view the full document!

lock_open Sign Up
Showing Page:
2/7
SOC 2061: midterm review Name:
_______________________________
Please be sure to show all your work on this exam, including any
formulas used, calculations conducted, and drawings used to arrive at
your answers!
P(X<35)=  




2. In a normal distribution, how many standard deviations from the mean is
the 95
th
percentile?
Answer
In a normal distribution the mean is 95
th
percentile by 1.96 standard
deviation.
Here, percentile is 95%
Z-score corresponding to 95
th
percentile is 1.96
Using Excel formula, =NORM.S.INV(0.975)
3. According to the central limit theorem what happens to the sampling
distribution of sample means as N becomes larger?
Answer
According to central limit theorem.the distribution becomes normal when as N
becomes larger.The sampling distribution would become more smoother and bell
shaped.
4. The Law School Admission Test (LSAT) is designed so that test scores are
normally distributed. The mean LSAT score for the population of all test-
takers in 2005 was 154.35 with a standard deviation of 5.62.
a. What is the mean of the sampling distribution for samples of size 100?
Answer
The mean of the sampling distribution of size 100 will be the mean LSAT
score of all test-takes which is 154.34.
b. What is the standard error of the sampling distribution for samples of
size 100?

Sign up to view the full document!

lock_open Sign Up
Showing Page:
3/7

Sign up to view the full document!

lock_open Sign Up
End of Preview - Want to read all 7 pages?
Access Now
Unformatted Attachment Preview
SOC 2061: midterm review Name: _______________________________ Please be sure to show all your work on this exam, including any formulas used, calculations conducted, and drawings used to arrive at your answers! 1. The mean age at first marriage for respondents in a survey is 23.33, with a standard deviation of 6.13 a. Calculate the Z score associated with an observed age at first marriage of 25.50 and explain what the Z score tells you. Answer 𝑧 − 𝑠𝑐𝑜𝑟𝑒 = 𝑋−𝑀𝑒𝑎𝑛 𝑠𝑑 = 25.5−23.33 6.13 = 0.3540 b. Calculate the observed age at first marriage associated with a Z score of -0.72. Answer Given ,z-score of -0.72 −0.72 = 𝑋−23.33 6.13 => 𝑋 = 18.92 c. What proportion of respondents were married for the first time between the ages of 20 and 30? Answer P(20 ...
Purchase document to see full attachment
User generated content is uploaded by users for the purposes of learning and should be used following Studypool's honor code & terms of service.

Anonymous
Really helpful material, saved me a great deal of time.

Studypool
4.7
Trustpilot
4.5
Sitejabber
4.4