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SLWK – 609 Research Methods- online- M. Secret
Podcast 5BASIC CONCEPTS OF RESEARCH DESIGN
http://www.screencast.com/t/3SYNmut6D7y
Problem Idea Theory
What How Who(variables) (methods) (sample)
Data Collection
Data Processing
Data Analysis
Discussion and Application
I I . Step by Step Overview of Research (Deductive) Process(Research Decision Tree)
Closer look at the What, How, Who Problem <<<>>> Idea <<< >>> Theory
What <<<>>> How <<<>>> Who(variables) (methods) (sample)
WHAT ARE YOU GOING TO OBSERVE –conceptualization and operationalization of variables.. -- some type of knowledge, attitude, or behavior.. How do you conceptualize these variables and how will you measure them ..
WHO WILL YOU OBSERVE --population –what are your choices here... probability or non-probability sample,
• what is your method..
• what type of research... experimental, non-experimental... ...
• How will you collect data
• Interview,
• questionnaire,
• secondary data analysis,
• observation..
Research designs and causality Research design means …..
the plan of collecting the data the way an investigator conducts a study the procedures employed to answer the research
problem or question methods and time of data collection the circumstances of the research setting.
Certain plans or designs help us to determine causality better than other plans or designs
Think of a continuum.. Not “either” “or”..
Nomothetic vs Idiographic Nomothetic .. Associated with quantitative
research methods… cause and effect determined by an experimental research design that examines relationship between independent and dependent variable
Idiographic.. Associated with qualitative research methods.. Cause and effect discussed in narrative form..based on qualitative data gathered and context
WHAT IS CAUSALITY or the CAUSAL EFFECT When the variation in one variable is related
to the variation in another variable When change in independent variable is
responsible for change in the dependent variable.
Idiographic researchers talk about Sequence of events rather than variables..
THREE CRITERIA NEEDED TO DETERMINE CAUSALITY
1. Statistical Relationship /association between the two variables– as one variable changes, so does another variable
2. Time order -- independent variable occurs before dependent variable
3. Relationship must not be spurious (i.e no confounding variable).. Nothing other than the independent variable creates the change
Language of quantitative research.. monethetic
Define ‘spurious’ False Bogus Fake
spu ri ous*⋅ ⋅ ˈspyʊər i əs/ [spyoo r-ee-uh s]–adjective 1.not genuine, authentic, or true; not from the
claimed, pretended, or proper source; counterfeit.; bastard.
*http://dictionary.reference.com/browse/spurious
Experimental vs non-experimental designs experimental designs –
Best to determine cause and effect Address all three criteria for causality Used for explanatory/evaluative purposes Data often collected at two points in time (pre-post)
non-experimental designs – Frequently only demonstrate association, not causality Often cannot demonstrate time order or non-spuriousness Used for descriptive/exploratory purposes Data often collected at ONE point in time
What is a true (classical) experimental designPROCEDURE Divide study participants into two groups
One group gets the treatment or the experiment The other doesn’t..
If after the treatment, there is a difference in results between the two groups, then can make some reasonable conclusion that the treatment caused the result
DISTINGUISHING CHARACTERISTICS True randomization...
every individual in the study has an equal chance of being in either the control or the experimental group....
attempts to insure is that there are no differences in the subjects of the groups which could account for change except for the intervention which was different for each group.
Manipulation the individual variable.. Gives intervention to experimental group and withholds from non-experimental (control) group In the study setting, researcher controls of as many factors as possible that could
influence the situation so that again you can be assured, or mostly assured, that the intervention is the cause of the change
How does an experimental study meet criteria for causalityAssociation/relationship
Dependent variable = stressIndependent variable = medication .. Give experimental group medication and control group no
medication
If experimental group has decrease in stress and control group does not, then there is a relationship..
Change in dependent variable (decrease in stress) is related to change in independent variable (medication, yes or no)
ASSOCIATION/RELATIONSHIP
No medication
Yes medication
No decrease in stress
Decrease in stress
How does an experimental study meet criteria for causality
Time order
Need to be sure that medication comes before the decrease in stress
Administer intervention.. Give medication Measure stress of both groups AFTER
medication
Time order and association
No medication
Yes medication
No decrease in stress
Decrease in stress
Independent variable = medicationComes BEFORE decrease in stress
Dependent variable = decrease in stresscomes AFTER medication
How does an experimental study meet criteria for causality … non-spuriousness
Random assignment means that the two groups are equal on all important characteristics..
Control for spuriousness because no variation between the groups on any variable other than the independent variable being tested
The only concept that varies is the independent variable .. Others (age, race, gender, IQ, income, social support, employment status are the same)
INTERVENING VARIABLES -- Mediating and Moderating Variables
Mediating -- some other variable comes between the independent and dependent variable.. A ‘third’ variable alters the relationship between the independent and dependent variable
Moderating – the relationship between the independent and dependent variable occurs only in some situations/circumstances
What are possible Mediating variables..
No medication
Yes medication
No decrease in stress
Decrease in stress
• Medication adherence• Other medications taken
Moderating variable Works only for people over the age of 35 Does not work for children or teens
Moderating variable = age group
Gap in the Research What is the
relationship between medication and stress in young adults – 19 -35
Thinking about your project – CLG work
If you are doing a quantitative study..
Identify possible intervening variables in your project
Longitudinal research design: Data are collected at two or more points in
time. Sometimes can be a quasi-experimental
design
Trend = data at two or more points in time from different samples of same population
Panel design = gather data from same sample at different points in time
Cohort study = can be either trend or panel. Have to be those who experienced similar event.
Unit of analysis vs sampling unit What is a unit of analysis?
the level of social life on which the research question is focused, such as individuals, groups, towns, or nations
How is it different from a sampling unit? the level of social life on which data is collected such as
individuals, groups, towns, or nations
Errors in Causal ReasoningEcological Fallacy and Reductionist Fallacy:
information collected from one unit of analysis is applied to another unit ..
Ex: I collect information from managers in social service organizations about turnover rates in that organization and generalize to the social service employees RATHER than social service organizations.
If a particular sports team is described as performing poorly, it would be fallacious to conclude that each player on that team performs poorly (ex from Wikipediahttp://en.wikipedia.org/wiki/Ecological_fallacy)
Validity Considerations – fill in the blank??
What <<>> How <<>> Who (variables) (methods) (sample)
________Validity
______validity
________validity
Measurement
Causal
Generalizability(external