Chapter 2: Theories & Models Week II – Slides 1 Chapter 2: Theories & Models Week II – Slides 2 What we are Covering: What is a theory? Where do theories come from? What is a model? Unit of analysis Logic models Usefulness of a logic model Additional issues in theory building Finding and focusing a research question 3 3 What is a theory? Theories are nets cast to catch what we call the world, to rationalize, to master, and to explain it. We endeavor to make the mesh ever finer & finer.“ Karl Popper, The Logic of Scientific Discovery 4 4 But, before theory . . . Ask a Question or Observe/Identify a Puzzle Goal: General Explanation What is the general phenomenon you are seeking to explain? Think in terms of concepts, not specific examples Primary interest: Explain change (a.k.a. variation) in the phenomenon of interest (a.k.a. dependent variable) 5 5 What is a theory? Theories identify key variables So we know what concepts to measure and observe Theories tell causal stories Often focusing on just one cause at a time Example: broken windows theory, which looks at the variable disorder as a possible factor in crime Theories explain variation 6 6 Dimensions & Variation Does the variation we are interested in occur over time, across units, or both? Spatial Variation Multiple units are measured at one moment in time Cross Sectional (CS) (e.g., # of giving campaigns by each non-profit in Broome County, in 2020) Temporal Variation Repeated measurement of one unit at different moments in time Time-Series (TS) (e.g., # Broome county residents diagnosed each day with Covid19 from March 15th – September 1st) 7 7 Cross-sectional variation example 8 8 Longitudinal variation example 9 9 Dimensions & Variation Can look at both space and time variation Time-series cross-sectional (TSCS) (e.g. Binghamton University mean GPAs across majors and semesters) 10 10 TSCS example 11 11 What is a theory? Theories generate testable hypotheses Hypotheses are predictions of what will happen if a theory is correct Hypotheses can be compared with the facts, and can potentially falsify a theory 12 12 What is theory? Theories focus on modifiable variables (Note: this is a more PA/PP specific concern) Social and policy research tends to focus upon modifiable variables as a way to offer guidance in policy and practice Modifiable and nonmodifiable variables Applied theories focus on modifiable variables—causes of an outcome that we can influence Nonmodifiable variables cannot be changed by policy or practice (example: policymaking in the US will be done under democratic process & norms) 13 13 Where do theories come from? Grand social theories Sometimes referred to as theoretical paradigms, which shape a researcher’s view of the variables and mechanisms involved in explaining human behavior Example: Rational-choice theory Individuals know all potential action that they can take W ...

1. Chapter 2:
Theories & Models
Week II – Slides
1
Chapter 2:
Theories & Models
Week II – Slides
2
What we are Covering:
What is a theory?
Where do theories come from?
What is a model?
Unit of analysis
Logic models
Usefulness of a logic model
Additional issues in theory building
Finding and focusing a research question
3
3

2. What is a theory?
Theories are nets cast to catch what we call the world, to
rationalize, to master, and to explain it. We endeavor to make
the mesh ever finer & finer.“
Karl Popper, The Logic of Scientific Discovery
4
4
But, before theory . . .
Ask a Question or Observe/Identify a Puzzle
Goal: General Explanation
What is the general phenomenon you are seeking to explain?
Think in terms of concepts, not specific examples
Primary interest:
Explain change (a.k.a. variation) in the phenomenon of interest
(a.k.a. dependent variable)
5
5
What is a theory?
Theories identify key variables
So we know what concepts to measure and observe
Theories tell causal stories
Often focusing on just one cause at a time
Example: broken windows theory, which looks at the variable

3. disorder as a possible factor in crime
Theories explain variation
6
6
Dimensions & Variation
Does the variation we are interested in occur over time, across
units, or both?
Spatial Variation
Multiple units are measured at one moment in time
Cross Sectional (CS) (e.g., # of giving campaigns by each non-
profit in Broome County, in 2020)
Temporal Variation
Repeated measurement of one unit at different moments in time
Time-Series (TS) (e.g., # Broome county residents diagnosed
each day with Covid19 from March 15th – September 1st)
7
7
Cross-sectional variation example
8
8

4. Longitudinal variation example
9
9
Dimensions & Variation
Can look at both space and time variation
Time-series cross-sectional (TSCS)
(e.g. Binghamton University mean GPAs across majors and
semesters)
10
10
TSCS example
11
11
What is a theory?
Theories generate testable hypotheses
Hypotheses are predictions of what will happen if a theory is
correct
Hypotheses can be compared with the facts, and can potentially
falsify a theory

5. 12
12
What is theory?
Theories focus on modifiable variables
(Note: this is a more PA/PP specific concern)
Social and policy research tends to focus upon modifiable
variables as a way to offer guidance in policy and practice
Modifiable and nonmodifiable variables
Applied theories focus on modifiable variables—causes of an
outcome that we can influence
Nonmodifiable variables cannot be changed by policy or
practice
(example: policymaking in the US will be done under
democratic process & norms)
13
13
Where do theories come from?
Grand social theories
Sometimes referred to as theoretical paradigms, which shape a
researcher’s view of the variables and mechanisms involved in
explaining human behavior
Example: Rational-choice theory
Individuals know all potential action that they can take
Will select decision which maximizes their benefits (utility)

6. 14
14
Where do theories come from?
Academic disciplines
Such as political science, psychology, economics, etc.
Induction
Building up theory from empirical evidence and observation
Important caution about induction: You cannot test an inductive
theory with the same set of facts used to create the theory
Deduction
Starting from initial ideas or logical principles
Often theory comes from both thought processes
15
15
Where do theories come from?
Exploratory and qualitative research
Linking threads of empirical evidence from exploratory studies
in a field
Qualitative research often used to generate theory
This is very hard to do! But, when done well, is usually the
most valuable research in the discipline.

7. 16
16
Where do theories come from?
Theories, norms, and values
Scientific theories are positive—about how things are
Not normative—about how things should be
Still theories reflect values, beliefs, and interests
(Example: we study human rights violation because we
normatively care about curtailing them in the future)
17
17
What is a model?
A graphical or mathematical representation of two items
Variables
That can take on different values or assume different
attributes—they vary
Relationships
That show how change in one variable produces change in
another variable

8. 18
18
Why do we do this?
It forces you to make your assumptions explicit
Establishes that implications follow logically from assumptions
19
19
More on assumptions
Explicit statement of our assumptions leads us to think precisely
about our concepts
What are the precise definitions?
Thinking about the assumptions could lead to promising lines
of research
Are the assumptions in a well-known theory flawed?
Assumptions do not always hold in all cases.
What are the implications if the assumptions do not hold?
20
20

9. Why do we do this?
Empirical tests of hypotheses are not the only way in which we
evaluate theories: we also evaluate them on logical and other
grounds.
It is worth our time to “kick the tires” before we invest a lot of
time collecting data
21
21
What question should we ask during this stage?
Is your theory causal?
It should explain how and why change in the values of the
independent variable change the values of the dependent
variable.
Does your theory generate testable hypotheses?
For a theory to be testable, it must be falsifiable
You should justify how your measurements match your
concepts
22
22
Hallmarks of a good model
Keep it simple
Connect x and y via the shortest explanatory route

10. Parsimonious models are better models
Occam's Razor
Is your model novel and interesting?
Your model should make new predictions
Your model should not propose explanations that are obvious to
all
23
23
What is a model? A quick refresher
Independent and dependent variables
X Y
“Cause” “Effect”
Independent Dependent
Causal mechanisms
The process by which change in X is presumed to cause change
Y
24
24
Note: we use a ton of different terms here

11. Left-hand right-hand
They all mean the same thing
25
25
Path diagram – a basic bivariate design
26
26
Path diagram – a basic bivariate design
Q: Indentify the independent and dependent variables?
Q: What is the presumed causal mechanism?
27
27
What is a model?
Direction of a relationship
Positive (+) relationship
High values of X tend to occur with high values of Y
X and Y vary in the same direction

12. Negative (−) relationship
High values of X tend to occur with low values of Y
X and Y vary in the opposite direction
28
28
Positive relationship
29
29
Negative relationship
30
30
Positive or negative?
Are these examples of relationships positive, or negative?
Air po
31

13. 31
Unit of analysis
Unit of analysis
The objects or things described by the variables in a model
Same theory may use different unit of analysis
A good theory should – more often than not – explain patterns
across many different units
In longitudinal research, the unit of analysis includes the time
period
Days, months, quarters, years
32
32
Unit of analysis (income)
33
33
Unit of analysis
Broken Windows Theory
34

14. 34
Logic models
Also referred to as
Program theories
Outcome-sequence charts
Theories of change
Graphical models showing how a program produces desired
outcomes
35
35
Logic models
The simple bivariate model
A direct effect from the IV on the DV
36
36
Logic models
The simple causal model
A direct effect from the IV on the DV
Usually we will have variable names and give an expected

15. direction on the arrow
-
37
37
Logic models
The simple causal model
A direct effect from the IV on the DV
Usually we will have variable names and give an expected
direction on the arrow
Models are often bivariate, but reality is multivariate
38
38
Adding intervening variables
Intervening variables Variables that intervene between the
independent variables and dependent variables
Also known as mediators in some disciplines, or intermediate
outcomes in program evaluation
They help articulate the causal process(es) – sometimes termed

16. causal chains – through which X produces Y
39
39
Adding intervening variables
40
40
Adding intervening variables – An example
41
41
Adding intervening variables – An example
42
42
Small Class Sizes
+
One-on-one Attention
+

17. Higher Test Scores
Problems with poorly thought out path models
Stop and think considerations while developing
Is there reverse causation?
Is there spuriousness?
More on this in week 4
43
43
You can have more than one intervening variable
44
44
Why we use logic models
Helps identify previously unrecognized variables to track as
performance indicators
Helps in planning the design of a program evaluation
Suggests logical weak links a program

18. 45
45
A DIY guide to logic models
Start with a single outcome or Y variable
Add a single X variable representing the program
Put the program (X) on the left and the outcome (Y) on the right
Add intervening variables between X and Y
Distinguish causal “chains” from separate “pathways”
Look for links that need explanation—consider additional
intervening variables
Give nondirectional names to variables and add “+” or “–” signs
to the relationships (arrows)
Make sure there is not too much, or too little, detail for your
audience
46
46
Let’s practice

19. 47
47
Logic models in program implementation
Often logic models are used to represent implementation of a
program and include
Inputs
Financial, human, and material resources
Activities
Training, counseling, marketing, and other tasks
Outputs
The immediate products of activities (people trained,
vaccinations given, etc.)
Outcomes
The results, including short-term, intermediate, and long-term
outcomes
48
48
49
Additional issues in theory building

20. Moderator
A variable that influence (strengthens or weakens) the
relationship between two other variables
50
50
Additional issues in theory building
Aggregation problem and ecological fallacy
Relationships that hold at one unit of analysis may not hold at
more aggregated levels
Key takeaway – often our unit of analysis matters
Think carefully
51
51
Additional issues in theory building
Hierarchical (multilevel) models and contextual variables
It’s weird the book places this here. Revisit this after we have
covered regression for this to make more sense.
Key takeaways:
Many times we will have questions about society where

21. observations exist within groups:
Students within classrooms
Patients within wards
Citizens within counties
52
52
Additional issues in theory building
Variables that influence DVs that care about may be influenced
by either individual-level or group-level characteristics
Example: A student's success in the classroom may be a
function of both their socio-economic background (individual-
level variable) and the experience of the teacher (group-level
variable)
The group-level variables affect all students in the classroom
We have to use special modeling strategies to accurately capture
these affects in the real world
53
53
Additional issues in theory building
Theoretical research

22. Theoretical research uses existing facts to gain insight, make
valuable predictions and recommendations.
54
54
How to find and focus research questions
Research question
The question that motivated the researcher to do the study
Applied research questions
Arise from the practical concerns of policymaker s and
practitioners
A good research question . . .
should be answerable
may be descriptive or causal
should be positive, not normative
55
55
Logic Model Assignment (25 points – 10 for memo & 15 for
logic model)
Consider a policy or social program that actually exists, that
you would like to propose or that someone else has proposed.

23. Choose an area that interests you and that you know something
about. Prepare a description of the theory of the mechanism of
how your program works to affect the outcome.
If you are looking for a program – I recommend reading through
this report from UCLA on the impact of Washington DC’s
voucher program.
Write this up as memo (~ 400 words) to a boss or collaborator
who is working with you to develop the program. This is not
someone you need to convince about the importance of the
outcomes or the program.
Make sure that you including the following:
(1) What is (are) the outcome(s) (dependent variable(s)) the
program is designed to affect? If there are many outcomes,
restrict your analysis to one outcome or two closely related
outcomes. (For example, your program program’s goal might be
to raise high school graduation rates in urban areas and so the
outcome is graduation rate.) Make sure that you state the
outcome(s) explicitly.
(2) Describe your program—what it is. This should be as
explicit as possible, not vague generalities. This section should
be brief: a half double-spaced page at the most. Do not include
marketing or promotion: your reader does not need to be
convinced of the importance of the project. Write an objective
and concrete statement of what the program literally does but do
include implementation details.
(3) Using a path diagram and a narrative description, describe
your theory of how the program is supposed to work. Both the
path diagram and the narrative description should make clear
the mechanism(s) through which the program will affect the
outcome. So, if a link is not obvious, break it down into the

24. steps along the way, illustrating the intervening variables.
This section should illustrate to your readers why they should
believe that the program will work—will affect the outcome(s).
It should also make clear what the weak linkages are.
This part (3) is the main focus of the assignment.
Notes and advice:
· The circles represent variables and the arrows represent causal
effects. Make sure that you understand clearly the unit of
analysis in your theory—the individuals to whom the variable
applies: For example, is the program working on students, on
schools, on cities?
· There can be many mechanisms through which a program
works. If so, pick only a couple and just note that there are
other mechanisms. These should be more detailed than the logic
models you see in many grant proposals and papers. Each link
should be spelled out and made believable.
· Draw your logic model by hand. Using software takes
unnecessary time and (much more importantly) makes it hard to
insert extra variables and arrows or to change what is there. If
you absolutely must draw this in software, do not do that until
the last possible point when you have already finalized your
logic model by hand. To submit the logic model by email scan
just the diagram part.
· Do not include introductions, motivations, background,
marketing and so on.
· Do not include inputs, resources, or (detailed) activities. This
logic model is not an implementation-oriented one: It focuses
on mechanism. Implementation is done more effectively after

25. you understand clearly the mechanism. So, this logic model
should not look like Figure 2.9. It should look more like Figure
2.8 or the top of p. 45 but with more details (e.g., more
branches, more intervening variables).
· Do use the tips on pp. 43-45. These tips were developed based
on commonly made errors!
· Check that each separate causal link makes sense isolated.
Check that you are not missing causal links between variables
on the page.
Rubric for Logic Model Assignment
Issue
A level work
B level work
C level work
F level work
Independent variable
(program)
Clearly defined indep var in narrative and path diagram
All effects on outcome (except contextual vars) lead ultimately
from indep var
Clearly defined indep var in narrative and path diagram
Some effects on outcome lead ultimately from indep var
Some definition of indep var in either narrative or path diagram
No clearly defined indep var
Dependent variable (outcome)
Clearly defined Dep var in narrative and path diagram
No other unspecified outcomes are de facto outcomes

26. Clearly defined dep var in narrative and path diagram
Almost no other unspecified outcomes are de facto outcomes
Some definition of dep var in either narrative or path diagram
Other unspecified outcomes are de facto outcomes
No clearly defined dep var
Intervening variables
Clearly defined Interv variables in narrative and path diagram
The bulk of preceding variables are logical causes and
following variables are logical consequences
Does not confuse process and mechanism
Mostly clearly defined Interv variables in narrative and path
diagram
Most of preceding variables are logical causes and following
variables are logical consequences
Does not confuse process and mechanism
Some definition of interv variables in either narrative of path
diagram
Some of preceding variables are logical causes, and some
following variables are logical consequences
Confuses process and mechanism
Intervening variables are not variables
Preceding variables are not logical causes and following
variables are not logical consequences

27. Completely substitutes process for mechanism
Issue
A level work
B level work
C level work
F level work
Mechanics of Assignment
Narrative of mechanism is clear, concise and avoids marketing
in favor of program description.
Clearly describes variables and mechanisms.
The bulk of path diagram has clearly drawn variables, explicit
relationship arrows, and includes signs to show positive or
inverse causal effects
Narrative portion is clear, concise and contains little marketing
in favor of program description.
Describes variables and mechanisms,
Most of the path diagram has clearly drawn variables, explicit
relationship arrows, and includes signs to show positive or
inverse causal effects
Narrative portion is confusing and/or contains mostly program
marketing language.
Path diagram is missing some variables and/or some arrows and
signs
Narrative does not explain the program or variables.
Path diagram missing many arrows and signs.
Writing quality

28. Writing is very clear
Arguments are cogent &persuasive
Organization is sensible & clear
Language is correct and concise
No repetition
Writing is fairly clear
Arguments are fairly cogent & persuasive
Organization is mostly sensible & clear
Language is mostly correct
Some unnecessary repetition
Writing is unclear
Arguments are not cogent & persuasive
Poor organization
Language has mistakes
Much unnecessary repetition
Writing is unclear
No arguments are made

29. No organization
Language has many mistakes
Much repetition