Five Types of Quantitative Research

EDRM 700
GREDLER
Five Types of Research
Experimental Research – One or more aspects of a situation are manipulated under carefully
controlled conditions and pre-selected outcomes are measured. Experimental studies,
therefore, are intervention studies.
Example: Does peer tutoring produce a greater understanding of science for sixth-grade
students than small-group discussions?
The researcher selects a sample of subjects and divides the sample into the number of
groups needed to test the hypotheses. In the above example, method of instruction is
manipulated: A peer tutoring method is assigned to one-half of the students, and smallgroup
discussion is assigned to the other half. At the end of six weeks, science
achievement is measured using an appropriate instrument, and the two groups are
compared.
Other examples:
Does client-centered therapy lead to higher satisfaction in adult clients than traditional
therapy?
Does an incident-based approach to discussing bullying raise the confidence level of
third-grade children?
Key features:
A planned intervention
Two or more groups compared on a quantitative outcome
Single-subject research – the study of the effects of an intervention on the behavior of one
subject at a time; typically implemented in situations in which group designs are not
appropriate. Observation is the typical method of data collection.
Example: What are the effects of self-recording one’s actions on off-task behavior for a
high-school student with an attention-deficit hyperactivity disorder?
Does a reinforcement program for hand-raising reduce the incidents of screeching to get
adult attention in an autistic eight-year-old boy?

Key characteristics:
A planned intervention
One research subject only
Measurement of a quantitative outcome
Correlational Research – to determine whether, and to what degree, a relationship exists
between two or more characteristics; sometimes used to make predictions about certain
behaviors.
Example: How well do prior grades and student self-directedness predict science
achievement in middle school?
The researcher selects a sample of subjects, obtains quantitative measures of the targeted
characteristics, and calculates the relationship.
Other examples: Is self-regulation related to math achievement in high school students?
Is there a relationship between a mindful approach to problem solving and self-regulation
in middle school students?
Key features:
NO INTERVENTION
One group only
At least two measurements
Causal-comparative research – also referred to as “ex post facto” (after-the-fact research) –
attempts to associate differences that already exist between or among groups of
individuals with differences in a particular characteristic. Unlike experimental research,
the researcher does not create the difference between or among the groups. Instead, the
difference is (a) a pre-existing characteristic that cannot be manipulated (age, gender) or
(b) a characteristic that cannot be manipulated ethically or easily (teaching style).
Example: Do 10-year-olds of different gender differ in linguistic ability?
Two groups of subjects that differ on an existing characteristic are measured on some
attitude, skill, or other characteristic to determine if there are differences.
Note: Interpretations of causal-comparative research are limited; the researcher cannot state that
the identified factor is the cause – only that there is a difference between groups.

Other examples:
Do middle-school teachers behave differently to students of different genders?
Do boys who attended kindergarten score higher on social adjustment than boys who did
not attend kindergarten?
Key features:
NO INTERVENTION
A pre-existing characteristic is the focus of the research
Two or more groups
Measurement of a quantitative outcome
Descriptive or Survey Research – information is collected from a sample in order to describe
some aspects or characteristics of the larger group to which the surveyed individuals
belong.
Example: What are the views of beginning teachers in District X about the mentoring
system for new teachers?
The researcher selects a sample of subjects, administers the survey, and, typically, reports
the percentages of respondents who respond differently to the questions.
Other examples:
How do parents in school district Y feel about the middle-school counseling program?
What are high school teachers’ views of the dimensions of effective school leadership?
Key features:
NO INTERVENTION
A defined group
Administration of surveys or interviews
Typically, calculation of percentages of respondents on the answers