Cinzia Yuet Tung Lau
April 5th, 2008
Statistics 408
Homework Set 8
2008
1. Why cant one know the cause of an event?
The cause of an event is a statement about the future. However, all
measurable features are based on the past or the present. As no one can
Steven Katofiasc
Professor Edward Rothman
Mastery #4
Sec. 003
Principle: Pipe Smokers Paradox
I will provide an example to illustrate why the Pipe Smokers Paradox is true.
Suppose that life expectancy among individuals in the United States that are marrie
Eric Tang
Homework Set 4
Stat 408
Fall 2016
1. Explain what is meant by a stable system. Can you know, by observing the outcomes of a
system whether it is stable?
A stochastic system is said to be stable if the outcomes are identically distributed.
For th
Eric Tang
Homework Set 5
Stat 408
Fall 2016
1. Explain why we might imagine that earning a PhD degree extends your life-length.
We might think that earning a PhD degree extends your life-length because say
most people who earn a PhD are usually around 30
Eric Tang
Statistics 408
Fall 2016
Homework Set 9
1. Provide an example to illustrate how we can estimate the proportion of people who use
an illegal drug?
2. Indicate how smoothing of data can create the appearance of cycles.
3. Describe the four compone
Homework 6
Stat 408
Fall 2016
Review Questions
Do not submit your answers to GSI
1. Explain why the purpose of a company cannot be either of the following:
i. Maximize Profits
ii. Gain the largest share of the market
2. Explain why when we do not achieve
Eric Tang
Statistics 408
Homework Set 03
Fall 2016
1. The physician claims that the probability that a patient has a viral infection is 95%. What
does this statement mean (provide an operational definition for this measure)? Is this a
property of the indi
Eric Tang
Homework Set 7
Statistics 408
Fall 2016
1. Describe how the range, mean absolute deviation, the variance and the entropy measures
are calculated as measures of variation.
Range: difference between the maximum and minimum value of a data set.
Mea
Eric Tang
Statistics 408
Homework Set I
Fall 2016
1. What is a system? Provide an example.
A system is an assortment of mechanisms that work together repeatedly to
achieve a common goal. An example of a system would be our school system
(purpose = to crea
Statistics 408
Homework Set 10
Fall 2016
1. Explain when an extrinsic reward may not undermine intrinsic motivation?
2. When and why would enlargement of a committee not be helpful?
3. Why, when a problem is present in a system, would we need to look outs
STATS 408 Review
1.
2.
3.
4.
5.
6.
7.
8.
Variance (measurement)
Variance (sources)
Bias
Experiments
Learning Challenges
Regression Effect
Misc
System of Profound Knowledge
MEASUREMENT
Measurement you use are appropriate for certain circumstances
Each of t
Stats 408 Exam 2 review
Review:
1.
2.
3.
4.
5.
6.
7.
8.
Var (measure_)
Var (sources)
Bias
Experiments
Learning challenge
Regression effect
Miscellaneous
System of confound knowledge
4 measures of variation - Each measure has a limitation need to know them
Syllabus
Statistics 408
Problem Solving: A System Approach
Fall 2016
Syllabus
1. There are no recitation meetings during the first week of class.
2. Recitation/Discussions begin September 15, 2016 .
3. Homework assignments are found at the class Canvas si
1a) What is a stable stochastic system with respect to outcomes described by the random
variable Y?
A stable stochastic system is one where random variables (Y1, Y2, , Yn) are
identically distributed s.t. the probability distribution is the same for every
Problem Solving: A
System Approach
Fall 2016
Lecture Week 10
Bias
Selection Bias
Respondent Bias
Scientist Bias
Interpretation/ Intervention Bias
Selection Biases
1. Target of the study and the context or set we study may Differ
Enumerative v Analyt
Statistics 408
Lecture Week 08
Fall 2016
Sources of Variation
1. Operational Definitions
2. Complexity
Each additional source of variation increases variance
Measured scores will have more variation than true scores (same operational
definition)
Regr
Statistics 408
Fall 2016
Week 11
How to Run an Experiment
We want to learn acquire useful theory and then apply what we find
useful.
Constraints: Sample size, biases
Approach involves several elements:
1. A control or several controls
2. Balance
3.
Statistics 408
Homework Set 02
Fall 2016
1. Suppose we find that among couples that have lived together before they marry 60% end in
divorce. Further, among couples that did not live together before they marry 45% end in
divorce. Identify a stratifying va
Eric Tang
Statistics 408
Homework Set 08
Fall 2016
1. Provide a situation where rule 2 of the funnel experiment may provide a useful model. In
your response indicate the role of funnel, target and the beans location in the context of
the example.
In regar
Cinzia Yuet Tung Lau
Statistics 408
Homework Set II
Winter 2008
1. Suppose we find that among couples that have lived together before they marry 60%
end in divorce. Further, among couples that did not live together before they marry
45% end in divorce. Id
Statistics 408
Winter 2016
Week 05
Modeling the Outcome of a Stable
System
1. For continuous outcomesor those we choose to model as
continuoususe a density function
2. For discrete outcome random variables, we model the outcomes
with a probability mass
Problem Solving: A System
Approach
E Rothman
Statistics 408
0. Outline of Course
Grading Process and Expectations
Models
Problem Solving: A System Approach
1. January, 7, 2015
2. Statistics 408
3. E Rothman
275 West Hall
erothman@umich.edu
Office Hours
Statistics 408
Week 02 2015
Last Weeks Principles
1. Everyone doing their best my not be best
-Interdependence
-Series System
2. High efficiency of every component may
not be effective
3. Optimization of a model may not help us
improve the world the mode
Statistics 408
Week 14
Winter 2015
Barriers
1. Lack of Constancy of Purpose
2. Emphasis of short term profits
3. Evaluation of relative performance
4. Mobility of management
5. Operation based on the numbers alone
6. Excessive medical costs
7. Excessive c
Statistics 408
Lecture Week 06
Winter 2015
Growing an Investment
Suppose the investment grows at different
rates each year. Find a number that reflects
the fixed annual growth rate equivalent to the
variable growth rates.
Example: Choose one of the foll
Statistics 408
Lecture Week 13
Winter 2015
Deming 14 Points
1. Create Constancy of Purpose
Everything is directed at the purpose of the system.
Changing the target can be very hard and require
major changes.
So make the purpose general-For instance mak
Statistics 408
Winter 2015
Lecture Week 10
Bias
Selection Bias
Respondent Bias
Scientist Bias
Interpretation/ Intervention Bias
Selection Biases
1. Target of the study and the context or set we
study may Differ
Enumerative v Analytic Investigations
Enu
Statistics 408
Winter 2015
Lecture Week 07
Measures of Variation
Range
Mean Absolute Deviation
Variance standard deviation
Entropy
Range
Range= largest value minus the smallest value
Simple to compute
Ex 1, 3, 7 has a range of 7-1 or 6
However, when we wa
Statistics 408
Winter 2015
Week 12
Laws of System Thinking
1. Todays problems may come from yesterdays
solutions. (Wack-a-mole)
2. The harder we push, the harder the system pushes
back. (Compensating feedback)
3. When our toolkit is filled with hammers
Statistics 408
Lecture Week 13
Winter 2015
Deming 14 Points
1. Create Constancy of Purpose
Everything is directed at the purpose of the system.
Changing the target can be very hard and require
major changes.
So make the purpose general-For instance mak
Statistics 408
Lecture Week 12
Fall 2016
Strength of a Relationship
When the two variables are modeled as a continuous variable-x=income, y=IQ we can use a Pearson r to measure strength of the
(linear relationship)
The formula for r is easier to write w
Steven Katofiasc
Professor Edward Rothman
Mastery #5
Sec. 003
Principle: When the rates r1, r2, rn Fluctutate: The Geometric Mean is less than the
Arithmetic Mean and the Disparity is Larger (The Greater the Variation in the Rates)
I will provide an examp
Steven Katofiasc
Professor Edward Rothman
Mastery #7
Sec. 003
Principle: The Illusion of Taking Charge is a Learning Disability
I will provide an example to illustrate why The Illusion of Taking Charge is a learning
disability is true. First we have to st
Steven Katofiasc
Professor Edward Rothman
Mastery #9
Sec. 003
Principle: The Parable of the Boiling Frog is a Learning Disability
Learning is the acquisition of useful theory that we act on. A learning disability is when it keeps
you from acquiring useful
Steven Katofiasc
Professor Edward Rothman
Mastery #11
Sec. 003
Principle: The Intrinsic Desire to Learn can be Undermined by Extrinsic Rewards
I will provide an example to illustrate why The Intrinsic Desire to Learn can be
Undermined by Extrinsic Rewards