Download Data - Statistics

Stat 350 Lab Session
GSI: Yizao Wang
Section 016 Mon 2pm30-4pm MH 444-D
Section 043 Wed 2pm30-4pm MH 444-B
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Outline
• First midterm exam reminder
• Big ideas review
• Qwizdom and non-qwizdom review
questions
• In lab project (ILP) on proportion
Today’s Qwizdom question is anonymous, you don’t have
to login with your UMID.
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First Midterm Exam
• 14th Feb. 6pm-7pm30 1324 EH
• Material:
Ch. 1, 2, 3, 4, 7, 8, 9.1-9.4, 10.1-10.3, 12.1-12.3, 12.5
HW 1-4 and all lab material
• Bring: PICTURE ID, Pen/pencils, erasers, and a
calculator. Formula cards with tables will be provided
with the exam.
• Alternate, randomized seating will be used in the exam rooms.
• No cell phones, beepers, palm pilots allowed in the exam rooms.
• All bags/backpacks will be placed against the exam room wall, so
the less extra things you bring, the better.
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Data
• We’ve talked about two broad types of
data this semester
• Do you remember what they are?
4
Probability
• We learned several rules for calculating
probabilities of events
– E.g. the event ‘Tails’ in the flip of a fair coin
• Special relationships between two events
– Mutually exclusive
– Independent
– Could you provide definitions and examples of
each?
5
Random Variables
• We’ve talked about two types of random
variables
– Can you name them?
• We’ve talked about three different models
(i.e. distributions) for random variables
– Can you describe them (be specific)?
– Can you find probabilities under each?
– Do you know which model is appropriate for
each type?
6
Sampling Distribution of p-hat
• Can you describe what the sampling
distribution of p-hat is?
• Do you know when to use it?
– When the problem asks you to find a
probability for a sample proportion
– When the sample size is large enough:
np≥10, n(1-p) ≥10
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Confidence Intervals for p
• Useful when we want to provide a range of
reasonable estimates for the population
proportion
• Do you know how to interpret the
confidence level?
• Do you know how to use a confidence
interval to make a decision, and under
what conditions this would be appropriate?
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Hypothesis Testing for p
• Useful for making a Yes/No type decision
about particular value(s) of a population
proportion
• Do you know the 5 steps of hypothesis
testing?
• Can you interpret and calculate a test
statistic?
• Can you interpret and calculate a p-value?
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