Transcript Causal Comparative Studies

Quantitative Paradigm:
Causal Comparative &
Correlational Studies
Nawwar Zada
* Qualitative and Quantitative Defined
- The simplest way to distinguish between
qualitative and quantitative may be to say that
qualitative methods involve a researcher describing
kinds of characteristics of people and events
without comparing events in terms of
measurements or amounts.
- Quantitative methods, on the other hand, focus
attention on measurements and amounts (more and
less, larger and smaller, often and seldom, similar
and different) of the characteristics displayed by the
people and events that the researcher studies.
Characterization of Qualitative
by Set of Writers :
1- Qualitative research is multi-method in focus,
involving an interpretive, naturalistic approach to
its subject matter. This means that qualitative
researchers study things in their natural settings,
attempting to make sense of, or interpret
phenomena in terms of the meanings people bring
to them.
- Qualitative research involves the studied use and
collection of a variety of empirical materials-case
study, personal experience, introspective, life story,
interview, observational, historical, interactional,
and visual texts that describe routine and
problematic moments and meanings in people's
lives. (Denzin & Lincoln, 1994, p.2)
2- Qualitative researchers seek to make sense of
personal stories and the ways in which they
interact. Qualitative inquiry is an umbrella term for
various philosophical orientations to interpretive
research.
For example, qualitative researchers might call their
work ethnography, case study, phenomenology,
educational criticism, human ethnology, ecological
psychology, holistic ethnography, cognitive
anthropology, ethnography of communication,
symbolic interactionism, micro-ethnography,
ethnomethodology, and postmodern ethnography
(or) partid-patory research. (Glesne & Peshkin,
1992, pp. 1)
While Quantitative is
Characterized by Two Sets of
Writers as Following:
1. Quantitative research uses numbers and
statistical methods. It tends to be based on
numerical measurements of specific aspects of
phenomena; it abstracts from particular instances
to seek general description or to test causal
hypotheses; it seeks measurements and analyses
that are easily replicable by other researchers.
(King, Keohane, & Verba, 1994. pp. 3-4)
2. Quantitative researchers seek explanations and
predictions that will generalize to other persons
and places. Careful sampling strategies and
experimental designs are aspects of quantitative
methods aimed at produce generalizable results.
In quantitative research, the researcher's role is to
observe and measure, and care is taken to keep the
researchers from “contaminating" the data through
personal involvement with the research subjects.
Researchers "objectivity" is of utmost concern.
(Glesne & Peshikin, 1992, p. 6)
* Types of Quantitative Researches:
1- Survey research
2- Causal-comparative research
3- Correlational research
4- Experimental research
* Data Collection:
Data collection is the process by which the
researcher collects the information needed to
answer the research problem.
* Data Collection Tools:
 Questionnaire
 Checklist
 Distribution
 Interview
 Observation
 Records
 Experimental Approach
 Survey Approach
CAUSAL-COMPARATIVE METHOD
OR
EX POST FACTO RESEARCH
- Causal-comparative research looks to uncover a
cause and effect relationship. This research is not
conducted between the two groups on each other.
Rather than look solely for a statistical relationship
between two variables it tries to identify,
specifically, how the different groups are affected
by the same circumstance. Causal-comparative
research involves ‘comparison’.
- In causal-comparative research the study of two
or more groups is done without focusing on their
relationship. As always the use of statistical
analysis is engaged to synthesize the data in a
clear method for presentation.
* Definition:
Ex post facto means "from after the fact" (Gay,
1976). In simple terms, in ex post facto research,
the researcher investigates a problem by studying
the variables in retrospect. It is research in which
the dependent variable is immediately observable
and now your main concern is to find out the
antecedents that gave rise to this consequence.
* Definition:
Kerlinger (1973) defines ex post facto as
"systematic empirical inquiry in which the scientist
does not have direct control of independent
variables because their manifestations have already
occurred or because they are inherently not
manipulable. Inferences about relations among
variables are made, without direct, intervention
from concomitant variation of independent and
dependent variables."
* Definition:
Gay (1976) says that it is that research in which the
researcher attempts to determine the cause, or
reason, for existing differences in the behavior or
status of groups of individuals. In a sense, the
researcher observes that groups are different on
some variable and then he attempts to identify the
major factor or factors which have caused this
difference.
* Definition:
- In other words, Causal comparative study is a
form of study that tries to identify and determine
the cause and effect of relationship between two or
more groups.
- Causal comparative study is a study in which the
researcher attempts to determine the cause, or
reason, for pre-existing differences in groups of
individuals.
* Differences between Dependent and
Independent Variable:
- When it comes to experiments and data analysis,
there are two main types of variables: dependent
variables and independent variables. It’s easy to
get these mixed up, but the difference between
dependent and independent variables is
simple. Here is a quick and easy definition of each
one, along with some examples.
* Differences between Dependent and
Independent Variable:
- Dependent Variable:
This is the output variable you are really interested
in monitoring to see if it was affected or not. It can
also be called the “measured variable,” the
“responding variable,” the “explained variable,”
etc. I think it is easy to remember this one because
it is dependent on the other variables.
Example 1: Golf Balls
Suppose you want to test golf ball flight distances, so you set
up a simple experiment in which various golf balls are placed
into a mechanical chute and fired into the air.
The variable you really care about, the “output” or dependent
variable is golf ball distance.
Independent variables are the variables you are going to test
to see how they affect distance. In this case, they are going to
be things like air temperature, golf ball brand, and color of
the golf ball.
In the end, if you do a fancy regression analysis on all your
data, you are going to end up with a formula that looks
something like this: golf ball distance = 50 feet + air
temperature factor + golf ball brand factor + golf ball color
factor. See how all the independent variables (air temp,
brand, color) have an effect on the dependent variable
(distance)?
* Differences between Dependent and
Independent Variable:
- Independent Variables:
These are the individual variables that you believe
may have an effect on the dependent
variable. They are sometimes called “explanatory
variables,” “manipulated variables,” or “controlled
variables.”
Example 2: Ice Cubes
Here’s another simple example: Imagine that you have a
bunch of ice cubes and you want to test how long it takes
them to melt in various situations. You have an experiment
with 1,000 equally shaped ice cubes. Some of them are made
of frozen cranberry juice and some of them are frozen
lemonade. You are going to set some of them on a metal
sheet and others are going to be placed on a wooden
plank. Air temperature, wind, and every other condition you
can think of will remain constant.
So, in this case, your dependent variable is ice cube melting
time. Your two independent variables are: juice
type (cranberry or lemonade) and melting surface (metal or
wood).
* Differences and similarities between causal
comparative and correlational studies:
• Causal comparative study looks at differences
between groups while correlational study looks
for relationships of variables within a single
group.
• Causal comparative and correlational studies
are similar in that both used to examine
relationships among variables.
• Causal comparative includes categorical
independent and or dependent variable but
correlational study only includes quantitative
variables.
* Differences and similarities between causal
comparative and correlational studies:
• Causal comparative research provides better
evidence of cause and effect relationships than
correlational research.
• Like correlational research, causal comparative
research is sometimes treated as a type of
descriptive research since it too describes
conditions that already exist.
* Differences and similarities between causal
comparative and correlational studies:
• Causal comparative research attempts to
establish cause-effect relationships while
correlational research attempts to determine
whether, and to what degree, a relationship
exists between two or more quantifiable
variables.
• Causal comparative and correlational studies
are non-experimental methods.
* Types of causal comparative research (Ex Post
Facto):
• Retrospective causal comparative and
prospective causal comparative research.
• Retrospective causal comparative research
requires that researcher begins investigating a
particular question when the effects have already
occurred and the research attempts to determine
whether one variable may have influenced
another variable.
• Prospective causal comparative research occurs
when a researcher initiates a study beginning
with the causes and is determined to investigate
the effects of a condition.
* Application of Ex Post Facto Research:
Let us think of correlational studies. Some studies
identify dependent and independent variables.
Some researchers who employ the correlational
approach are merely interested in the relational
aspect of two variables without necessarily
assuming that one is a function of the other; e.g.
relationship between teacher behavior and pupil
behavior or between work attitude and job
satisfaction. This type of correlational studies does
not attempt to identify cause-effect relationships.
* Application of Ex Post Facto Research:
- Therefore, where hypotheses are stated in causeeffect relationship and where variables being
correlated are ex post facto, that is, their
manifestations have already occurred. The research
is actually ex post facto.
- Correlational and causal-comparative or ex post
facto researches are confused because of the lack
of manipulation common to both. There are
definite differences, however. Ex post facto studies
attempt to identify cause-effect relationships,
correlational studies do not.
* Limitations:
- There are three major weaknesses of ex post facto
research. These are:
First, the inability of the researcher to manipulate
the independent variables purposively; and second,
the researcher's lack of power to assign subjects
randomly to the group levels of the variables under
study. Put simply, ex post facto research lacks
control which actually is the best for a third major
weakness that of the risk of improper
interpretation.
* Limitations:
- Wiersma (1975) points out that "the interpretation of the
results of an ex post facto study should be supported by a
thorough knowledge of the independent variables in the
context of the dependent variables. Such knowledge will
tend to guard against profuse and improper
interpretations. Any conjectures should be categorized as
just that. The researcher should recognize the empirical
results of the study and should limit the discussion on
these results in preference to pursuing conjectures for
which there is little or no basis."
- This means that a third variable might have caused both
the identified cause and the effect. Thus in an ex post facto
study, the cause-effect relationships are at beat tenuous
and tentative.
* The Value of Ex Post Facto Research:
Many of the variables in social, psychological and
educational setting are certainly important areas of
study but which can impossibly be investigated
through true experimentation. Although direct
control is impossible, controlled inquiry can be
done in ex post facto and extraneous variable
control is certainly possible.
These make the research sensible and valid. For
this reason, findings, interpretations and
conclusions made in ex post facto research, when
done properly, will always be valuable to the
scientist and to the layman.
* References:
• Dependent vs. Independent Variables: What’s the Difference?. (2012).
Retrieved from
http://www.mymarketresearchmethods.com/dependentindependent-variables-whats-difference/
• Johnson, B. & Christensen, L. Educational Research: Quantitative,
Qualitative, and Mixed Approaches. California, SAG Publications, Inc.
• Klazema, April. (2014). Types of Quantitative Research for Students and
Researchers. Retrieved from
https://www.udemy.com/blog/types-of-quantitative-research/
• Nalzaro, Ludi Mae. (2012). METHODS OF DATA COLLECTION. Retrieved from
http://www.slideshare.net/ludymae/chapter-9methods-of-datacollection?related=2
* References:
• Sevilla, C. G., Ochave, J. A., Punsalan, T. G., Regala, B. P., & Uriarte, G. G.
Research Method. Quezon, Rex Printing Company, INC.
• Stejskal, Stella-Maria. (2007). Quantitative and Qualitative Research
Methods Are not and Should not Be Mutually Exclusive. Retrieved
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• Thomas, R. Murray. Blending Qualitative and Quantitative Research Methods
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