Transcript Chapter 2

Chapter 2
Understanding the Research
Process
Steps in the Research
Process
Narrow to
specific problem
Develop
approach
Identify question
State hypotheses
Identify sample
Design data collection plan
Select collection procedures
Choose
analysis
Implement plan
Prepare report
Review
literature
Types of Research Questions
• Descriptive
– Interview subjects, observe behavior, or
measure performance
• Difference
– Compare 2 groups
• Relationship
– Assess covariation between two variables
Selecting the Problem - Tips
1. While reading, attending lectures,
write down ideas immediately.
2. Research a subject for a paper.
3. What questions seem unresolved?
4. Challenge commonly accepted
beliefs.
5. Look at master’s & doctoral studies.
6. Discuss ideas, topics with
professors or other researchers.
Defining the Problem
• Literature search
– conceptual literature
– related research
• Consider your interest in the problem
• Consider the “importance” of the
problem
• Consider whether researching the
problem is a feasible task
Statement of problem
• problem statement: declarative
statement indicting question addressed
in research project
• Example: The focus of the study was to
determine whether particular variations
within the CHRNA4 gene are associated
with smoking behaviors.
Delimitations
• Description of subjects
• Description of variables
• Description of tests, instruments,
procedures
• Description of special equipment
• Type of training
• Time and duration of study
• Analytical procedures
Limitations
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Approach, design, method, techniques
Sampling problems
Uncontrolled variables
Errors in test administration or data handling
Generalizability of data
Representativeness of subjects
Compromises to internal and external validity
Reliability and validity of research
instruments
Assumptions
• Usually drawn from literature or
previous experiments
• Example: We assume the same genes
are important in different populations
for mediating smoking behavior. We
assume the genes contribute enough of
an effect to the behavior to be able to
be observed.
Variable
• Characteristic, trait, or attribute of a
person or thing that can be classified or
measured
Qualitative vs. Quantitative
• Qualitative variables
• Quantitative variables
– Measured in a numerical sense
– Discrete:
– Continuous:
Independent vs. Dependent
• Independent variables
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Experimental treatment
Variable that is manipulated or selected
Doesn’t change during research protocol
Active: manipulated or selected
Attribute: pre-existing (cannot be manipulated)
• Dependent variables
– Expected to change as result of independent
variable
– Observed & measured during research protocol
– Not under control of researcher
Extraneous variables
• Other factors that may influence the
dependent variable
• Aka: intervening variables, modifying
variables, confounding variables
• Source of unwanted or error variance
• Examples?
Control of Variables
• Random selection of subjects
• Equating by matching or some criterion
• Excluding the variable