Transcript 13-Review and Overview of the Course

CMNS 260: Empirical Communication Research Methods
13-Review and Overview of the Course
Professor: Jan Marontate
Teaching Assistants: Nawal Musleh-Motut, Megan Robertson
Lab Instructor: Chris Jeschelnik
School of Communication.
Simon Fraser University
Fall 2011
Outline of Class Activities Today
• Syllabus & Outline of Class Sessions
– Objectives
• Selected excerpts of lecture material to
review for final examination
• Study tips for final examination
• Discussion of last assignment
Course content
• Introduce different forms of research
• Analyze relationships between goals,
assumptions, theories and methods
• Study basic data collection and analysis
techniques
• Research process—focusing on empirical
methods
Why study methods? Practical aspects
– learn to read other people’s research & critically
evaluate it
– learn ways to find your own “data” to answer your
own research questions
– acquire skills potential employers seek
– self-defense (against misinformation) &
responsible citizenship
The
Research
Process
Babbie (1995: 101)
Why study methods?
– “Knowledge is power” (to acquire skills for social
action or change)
• “Savoir pour pouvoir, Pouvoir pour prévoir” (Auguste
Comte)
• «To know to do (have power), to do (have power) in order
to predict the future and plan for it »
– « Knowledge is understanding »
• “décrire, comprendre, expliquer ” (Gilles Gaston Granger)
• “to describe, to understand and to explain”
Research has the potential to inform
and misinform
• even well-done research is not always used
accurately
• some research is technically flawed
• knowledge of methods an important tool for
understanding logic and limits of claims about
research
Research Methodology (Scholarly
Perspectives)
• Process
– methods
– logic of inquiry (assumptions & hypotheses)
• Produces
– laws, principles and theories that can be tested
• (Karl Popper & notion of falsifiability for politically
engaged scholars interested in the fight against
genocide in the early 20th century)
Research has the potential to inform
and misinform
• even well-done research is not always used
accurately
• some research is technically flawed
• knowledge of methods an important tool for
understanding logic and limits of claims about
research
Other Ways of Knowing
– authority (parents,
teachers, religious
leaders, media gurus)
– tradition (past
practices)
– common sense
– media (TV. etc.)
– personal experience
Talk show host Oprah Winfrey
Cory Doctorow
Electronic Frontier Assoc. &
Boingboing.net
Ordinary Inquiry vs. Scholarly Inquiry
Risks of “Errors” associated with non-scholarly
knowledge
• selective observation--only notice some phenomena-miss others
• overgeneralization-evidence applied to too wide a range
of conditions
• premature closure--jumping to conclusions
• halo effect--idea of being influenced by prestige
Communication as a Science?
• Field more recent
– affiliations with the sciences, social sciences & the
humanities
• Scholarly work (like old ideas of science)
distinguished from mythology by methods
AND goals
• many different approaches
Relations between theory and empirical
observation
• Theory and empirical research
– Testing theories through empirical observation
(deductive)
– Using empirical observation to develop theories
(Inductive)
Empirical and Logical
Foundations of Research
(does not have to start with theory)
Theories
Empirical
Generalizations
The
Scientific
Process
Predictions
(Hypotheses)
Observations
Source: Singleton & Straits (1999: 27); Babbie (1995: 55)
Scholarly Communities--Norms
• universalism -- research judged on “scientific”
merit
• organized scepticism -- challenge and question
research
• disinterestedness-- openness to new ideas,
non-partisan
• communalism--sharing with others
• honesty
Research Questions
• Questions researchers ask themselves, not the
questions they ask their informants
• Must be empirically testable
• Not
– too vague
– too general
– untestable (with implicit, untested assumed outcomes)
Developing research topics
“Dimensions” of Research
Purpose of
Study
Intended Use
of Study
Treatment of Time
in Study
Exploratory
Descriptive
Explanatory
Basic
Applied
-Action
-Impact
-Evaluation
Cross-sectional
Longitudinal
-Panel
-Time series
-Cohort analysis
-Case Study
-Trend study
Space
Unit of
Analysis
(examples)
-dependent
-individual
-independent -family
-household
-artifact
(media,
technology)
Neuman (2000: 37)
Exploratory Research
• When not much is known about topic
• Surprises (e.g. Serendipity effect)
• Acquire familiarity with basic concerns
and develop a picture
• Explore feasibility of additional
research
• Develop questions
Descriptive Research
• Focuses on “who”, “what” and “how”
• Background information, to stimulate new
ways of thinking, to classify types, etc.
Explanatory Research
• To test theories, predictions, etc…
• Idea of “advancing” knowledge
Intended Use of Study
• Basic
• Applied
– action research (We can make a difference)
– social impact assessment (What will be the
effects?)
– evaluation research (Did it work?)
– needs assessment (Who needs what?)
– cost-benefit analysis (What is it worth?)
Basic or Fundamental Research
• Concerns of scholarly community
• Inner logic and relation to theoretical issues
in field
Applied Research
• commissioned/judged/used by people outside
the field of communication
• goal of practical applications
– usefulness of results
Types of Applied Research




Action Research
Social Impact Assessment
Needs Assessment
Evaluation Research
• formative (built in)
• summative (final outcomes)
 Cost-benefit analysis
Treatment of Time
 Cross-sectional
(one point in time)
 Longitudinal
(more than one point in time)
Main Types of Longitudinal Studies
•
Panel study
– Exactly the same people, at least twice
•
Cohort Analysis
– same category of people or things (but not exactly same individuals) who/which shared an
experience at at least two times
– Examples: Birth cohorts. Graduating Classes, Video games invented in the same year
2000
2010
41-50
51-60
61-70
71-80
41-50
51-60
61-70
71-80
•
Time-series
– same type of info., not exactly same people, multiple time periods, e.g. Same place
2006
Burnaby residents
•
2011
Burnaby residents
Case Studies may be longitudinal or cross-sectional
Lexis Diagram (To study Cohort
Survival)
Importance of Choosing Appropriate Unit
of Analysis
• example: Ecological Fallacy (cheating)
Ecological Fallacy
Ecological Fallacy
Ecological Fallacy & Reductionism
ecological fallacy--wrong unit of analysis
(too high)
reductionism--wrong unit of analysis (too low)
reductionism--wrong unit of analysis (too low)
Relationship of Theory & Empirical
Observation (Wheel of Science)
Deductive & Inductive Methods (p. 71)
Conceptualization & Operationalization of
Research questions
• Conceptualization:
Development of abstract concepts
• Operationalization:
Finding concrete ways to do
research
Reliability & Validity
 Reliability
 dependability
 is the indicator consistent?
 same result every time?
 Validity
 measurement validity - how well the conceptual and
operational definitions mesh with each other
 does measurement tool measure what we think ?
Hypothesis Testing
Possible outcomes in Testing
Hypotheses (using empirical research)
• support (confirm) hypothesis
• reject (not support) hypothesis
• partially confirm or fail to
support
• avoid use of PROVE
Causal diagrams
Direct relationship (positive correlation)
X
Y
X
Y
Indirect relationship (negative correlation)
Causal Diagrams
X
+
+
Y
Y
X
_
X1
Z
+
Y
_
X2
X1
+
_
X
+
Z
+
Y
Z
X2
+
Y
_
Neuman (2000: 56)
Types of Errors in Causal Explanation
• ecological fallacy
• reductionism
• tautology
• teleology
• Spuriousness
Double-Barrelled Hypothesis & Interaction Effect
Means one of THREE things
1
2
OR
Interaction effect
Recall: Importance of Choosing Appropriate Unit
of Analysis
• Recall example: Ecological Fallacy (cheating)
Ecological Fallacy (cheating)
Ecological Fallacy (cheating Box)
Ecological Fallacy & Reductionism
ecological fallacy--wrong unit of analysis
(too high)
reductionism--wrong unit of analysis (too low)
reductionism--wrong unit of analysis (too low)
Teleology & Tautology
tautology--circular reasoning (true by definition)
teleology--too vague for testing
Neuman (2000: 140)
Spurious Relationship
spuriousness--false relationship
(unseen third variable or simply not connected)
Neuman (2000: 140)
Example: Storks & Babies
– Observations:
– Lots of storks seen around apartment buildings
in a new neighbourhood with low cost housing
– An increase in number of pregnancies
– Did the storks bring the babies???
?
But...
• The relationship is spurious.
– The storks liked the heat coming from the
smokestacks on the roof of the building, and so
were more likely to be attracted to that building.
– The tenants of the building were mostly young
newlyweds starting families.
– So…the storks didn’t bring the babies after all.
Causal Diagram for Storks
• Stork = S
• Baby = B
S
• Newlywed = N
• Chimneys on Building = C
+
N
+
B
B
C
+
S
Another example of spurious relationships:
number of firefighters & damage
• The larger the number of firefighters, the
greater the damage
But...
• A larger number of firefighters is necessary to
fight a larger fire. A larger fire will cause more
damage than a small one.
• Debate about Hockey Riots in Vancouver.
– Did the size of the crowd & amount of drinking
cause the riots?
– Did bad planning and inadequate policing cause
the fire?
Causal Diagram
• Firefighter = F
• Damage = D
• Size of Fire = S
+
F
+
D
F
S
+
D
Ethics & Legality
Typology of Legal and Moral
Actions in Research
Ethical
Illegal
Only
Immoral
Only
Legal
Illegal
Both
Moral and
Legal
Both
Immoral
and Illegal
Unethical
Source: figure adapted from
Neuman (2000:91)
Privacy, Anonymity, Confidentiality
• privacy: a legal right (note : public vs.
private domain)--even if subject is dead
• anonymity: subjects remain nameless &
responses cannot be connected to them
(problem in small samples)
• confidentiality: subjects’ identity may
be known but not disclosed by researcher,
identity can’t be linked to responses
4-Measurement—Scales & Indices
(Part 2 of 2 slideshows)
Neuman & Robson
Chapter 6
•systematic observation
•can be replicated
Creating Measures
 Measures must have response categories that
are:
 mutually exclusive
 possible observations must only fit in one
category
 exhaustive
 categories must cover all possibilities
Composite Measures
• Composite measures are instruments that use
several questions to measure a given variable
(construct).
• A composite measure unidimensional (all
items measure the same construct)
– Indices (plural form of index) and scales
Logic of Index Construction
actions combined in single measure, often
an ordinal level of measurement
Logic of Scales
actions ranked
Logic Index--example
Logic Scale-example
Treatment of Missing Data
• eliminate cases with missing
data?
• substitute average score ?
• Guess ?
• insert random value ?
Rates & Standardization:
• deciding what measure to use for reference populations
example: employment rates
Sampling: key ideas & terms
Bad sampling frame
= parameters do not accurately represent
target population
– e.g., a list of people in the phone directory
does not reflect all the people in a town
because not everyone has a phone or is listed
in the directory.
Types of Nonprobability
Samples
4
Types of Probability Samples
link to useful webpage: http://www.socialresearchmethods.net/kb/sampprob.php
16
Stratified
Evaluating Sampling
• Is the sample representative of the population under
study?
• Assessing Equal chance of being chosen
• Examine Sampling distribution of parameters of
population
• Use Central Limit Theorem to calculate Confidence
Intervals and estimate Margin of Error
Asking
Questions
that can be
answered
Types of Surveys & Survey Instruments
• Self-administered Surveys
• Mail
• Web
• Surveys based on Interactive Interviews
• Telephone
• Online (interactive)
• Face-to-face
– Individuals
– Focus groups
• Survey Instruments:
– Questionnaires
• self-administered
• Respondent reads questions & records answers
– Interview Schedules
• interviewer reads questions & records responses
Main Types of Unobtrusive Measures
• Physical traces
– Erosion (ex. wear on floor in museum
displays as measure of popularity of display)
– Accretion (ex. garbage)
• Simple observation
• Media analysis such as content analysis,
critical discourse analysis (ex.
advertisements, news reports, films,
music lyrics etc…)
• Analysis of archives, existing statistics &
running records (ex. shoppers’ records,
library borrowers’ histories)
• Simple observation
Types of Equivalence for comparative
research using existing statistics
• lexicon equivalence (technique of back
translation)
• contextual equivalence (ex. role of religious
leaders in different societies)
• conceptual equivalence (ex. income)
• measurement equivalence (ex. different
measure for same concept)
Discrete & Continuous Variables
• Continuous
– Variable can take infinite (or large) number of values
within range
• Ex. Age measured by exact date of birth
• Discrete
– Attributes of variable that are distinct but not
necessarily continuous
• Ex. Age measured by age groups (Note: techniques exist
for making assumptions about discrete variables in order
to use techniques developed for continuous variables)
Cleaning Data
• checking accuracy & removing errors
– Possible Code Cleaning
• check for impossible codes (errors)
– Some software checks at data entry
– Examine distributions to look for impossible codes
– Contingency cleaning
• inconsistencies between answers (impossible
logical combinations, illogical responses to skip or
contingency questions)
Treatment of Missing Data (%)
• Comparison with medium & low collapsed
Table 5-1 Alienation of Workers
Table 5-1 Alienation of Workers
Level of Alienation
High
Medium & Low
No Response
Level of Alienation
High
Medium & Low
F
30
120
60
%
14
58
29
(Total)
(Total)
210
Non-respondents included
F
30
120
%
20
80
150
100
100
Non-respondents eliminated
Grouping Response Categories(%)
• Comparison of with high & medium response
categories collapsed
Table 5-1 Alienation of Workers
Table 5-1 Alienation of Workers
Level of Alienation
High & Medium
Low
No Response
Level of Alienation
High& medium
Low
(Total)
210
Freq
%
62
10
29
100
(Total)
150
Freq
%
87
13
Core Notions in Basic Univariate
Statistics
Ways of describing data about one
variable (“uni”=one)
–Measures of central tendency
• Summarize information about one variable
• three types of “averages”: arithmetic mean,
median, mode
–Measures of dispersion
• Analyze Variations or “spread”
• Range, standard deviation, percentiles, z-scores
Normal & Skewed Distributions
Details on the Calculation of Standard Deviation
Neuman (2000: 321)
The Bell Curve & standard deviation
If Time: Begin Bivariate Statistics (Results with
two variables)
• Types of relationships between two variables:
– Correlation (or covariation)
• when two variables ‘vary together’
– a type of association
– Not necessarily causal
• Can be same direction (positive correlation or direct
relationship)
• Can be in different directions (negative correlation or
indirect relationship)
– Independence
• No correlation, no relationship
• Cases with values in one variable do not have any
particular value on the other variable
Recall (Lecture 2)
*Types of variables*
• independent variable (cause)
• dependent variable (effect)
• intervening variable
– (occurs between the independent and the
dependent variable temporally)
• control variable
– (temporal occurance varies, illustrations later
today)
Causal Relationships
• proposed for testing (NOT like assumptions)
• 5 characteristics of causal hypothesis (p.128)
– at least 2 variables
– cause-effect relationship (cause must come before
effect)
– can be expressed as prediction
– logically linked to research question+ a theory
– falsifiable
Types of Correlations & Causal Relationships
between Two Variables
X=independent variable Y=dependent variable
• Positive Correlation (Direct relationship)
– when X increases Y increases or vice versa
X
+
• Negative Correlation (Indirect or inverse
relationship)
X
– when X increases Y decreases or vice versa
• Independence
– no relationship (null hypothesis)
• Co-variation
– vary together ( a type of association but not necessarily
causal)
Y
Y
Five Common Measures of Association
between Two Variables
General Idea of Statistical Significance
• In general English ‘significance’ means
important or meaningful but this is NOT how
the term is used in statistics
• Tests of statistical significance show you how
likely a result is due to chance.
Multi-variate Statistics: Elaboration Paradigm
(Types of Patterns)
• Replication: same relationship in both partials as in
bivariate table
• Specification: bivariate relationship only seen in one
of the partial tables
• Interpretation: bivariate relationship weakens greatly
or disappears in partial tables (control variable is
intervening—happens in between independent & dependent)
• Explanation: Bivariate relationship weakens or
diappears in partial table (control variable is before independent
variable)
• Suppressor: No bivariate relationship; relationshp
only appears in partial tables.
Elaboration Paradigm Summary
Study Tips for Final Exam
• Practice questions
• Other ideas for preparation