Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
An introduction to the concept of sampling distributions and estimators in statistics. It explains that a sample is a subset of a larger population and that statistics, such as mean and variance, can be calculated from a sample. The document also discusses the importance of sampling distributions in determining how close sample statistics are to the true population values. It includes exercises for identifying population, sample, and estimator, as well as calculating sample statistics and confidence intervals.
Typology: Study notes
1 / 9
This page cannot be seen from the preview
Don't miss anything!
What’s variability got to do with it?
1
Push and hold “Menu” button for three seconds to turn unit on
Should say “Enter session ID”
If not, need to push arrow until it asks for session ID
2
Type in “920661”
You must push “Send” to send a signalsignal
3
Enter your ID
Be sure to include leading zeros
E.g., type “000365781”
4
5
Type in your age
6
Press “YES” if the last digit of your ID is even (0 2 4 6 8)(0,2,4,6,8) Pres “NO” if the last digit of your ID is odd (1,3,5,7,9)
10
Press “YES” if the last digit of your ID is even (0 2 4 6 8)(0,2,4,6,8) Pres “NO” if the last digit of your ID is odd (1,3,5,7,9)
11
Order the choices to match the
terms:
a. Population b. Sample proportion c. Sample d. Population proportion
12
Samples are different, so proportions are different
How “close” is sample mean to truth?
Sampling Distribution will tell us!
13
Simple definition: a statistic is something you calculate from a sample
Hard definition: a statistic is a real-valued function of the samplefunction of the sample mean -- standard deviation -- the largest value
Each statistic has a distribution what are the possible values? how often do we expect those values to occur?
14
15
X X X
μ
Population
1 2 3
4
X X
X X
19
p^ ˆ p ˆ p ˆ
p
Population
(^1 ) 3
4
p p^ ˆ
p p
20
(1 ) ˆ ,
p p p N p n
X N
⎛ (^) − ⎞ ⎜⎜ ⎟⎟ ⎝ ⎠
⎛ ⎞
∼
X N , n
⎛ ⎞ ⎜ ⎟ ⎝ ⎠
∼
21
A (1- α)% confidence interval for μ is given by:
22
Has CEO pay increased?
Sample data Mean percentage increase = 6.9% Standard deviation of increase = 55%Standard deviation of increase = 55% N = 104
95% confidence interval
23
μ
μ
24
