Method of Writing
Research Papers 4
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TYPES OF NONEXPERIMENTAL RESEARCH
As indicated above, researchers only give treatments to
participants in experimental studies. In nonexperimental
studies, researchers observe or collect information from
participants
without
trying
to
change
them.
Nonexperimental studies take many forms because they
serve many purposes. The most common types of
nonexperimental studies are briefly described here.
Causal-comparative research, described in the previous
topic, is research in which researchers look to the past for
the cause(s) of a current condition. It is used primarily
when researchers are interested in causality but cannot
conduct an experiment for ethical or other limiting reasons.

Surveys or polls describe the attitudes, beliefs, and
behaviors of a population. To conduct a survey or poll,
researchers draw a sample of a population, collect
data from the sample, and then make inferences
about the population. For instance, a researcher could
survey a sample of individuals receiving SNAP benefits
(“food stamps”) to determine what types of food they
purchase with this benefit. The results obtained from
studying the sample could be generalized to the
population (assuming that a good sample has been
drawn). If a researcher is able to interview everyone
in a population (i.e., all individuals receiving SNAP
benefits) instead of drawing a sample, the study is
called a census.

A census is a count (or study) of all members of a
population. This is easy to remember if you consider
that the United States Census, completed every 10
years, strives to include every single person in the
United States. Unless a population size is small,
completing a census study can be quite expensive.
The anticipated cost of completing the 2020 census of
all 300+ million United States residents is $12.5
billion!

While surveys usually include hundreds or even
thousands of participants, a case study usually
involves only one. For instance, some important
theories in clinical psychology were developed from
intensive one-on-one case studies of individuals. In a
case study, the emphasis is on obtaining thorough
knowledge of an individual, sometimes over a long
period of time. Researchers do not confine
themselves to asking a limited number of questions
on a one-shot basis, as they would do in a survey.
In correlational research, researchers are interested
in the degree of relationship among two or more
quantitative variables.

For instance, scores on a college admissions test and
GPAs are quantitative (numerical), and because
individuals vary or differ on both of them, they are
variables. If a researcher conducts a study in which he
or she is asking, “Did those with high admissions
scores tend to earn high GPAs?” the researcher is
asking a correlational question. To the extent that the
relationship between the two variables is positive—
that is, the higher admission scores correspond to
higher GPAs—the researcher can assert that the test
successfully predicts GPAs.

So far, studies are cross-sectional, meaning they are a
snapshot of one moment in time. When researchers
repeatedly measure traits of the same participants to
capture similarity or change over a period of time,
they are conducting longitudinal research.
For instance, a researcher conducting longitudinal
research could measure the visual acuity of a sample
of infants each week for a year to trace visual
development. Other examples include educational
data, such as the Minnesota P-20, a statewide
educational data system that collects student data
from
pre-kindergarten
to
completion
of
postsecondary education to gauge the effectiveness
of various educational programs and initiatives.

Experiments and all the types of research mentioned
so far in this topic belong to the class of research
called quantitative research. A distinctive feature of
quantitative research is that researchers gather data
in such a way that the data are easy to quantify,
allowing for statistical analysis. For instance, to
measure attitudes toward Asian American
immigrants, a quantitative researcher might use a
questionnaire and count how many times
respondents answer “yes” to statements about Asian
Americans and then calculate the percentage who
answered “yes” to each statement.

By contrast, in qualitative research, researchers gather data
(such as responses to open-ended interview questions on
attitudes toward Asian Americans) that must be analyzed
through the use of informed judgment to identify major and
minor themes expressed by participants. Most published
qualitative research is collected through semi-structured
interviews in which there is a core list of questions from
which the interviewers may deviate as needed to obtain indepth information. Other differences between qualitative
and quantitative research are explored later. In addition, this
part describes qualitative research design in detail.

In historical research, information is examined in order to
understand the past. Note that good historical research is not
just a matter of developing a chronological list of so-called
facts and dates. Rather, it is an attempt to understand the
dynamics of human history. As such, it is driven by theories
and hypotheses. In other words, by reviewing historical
evidence, such as newspapers or other archival documents of
the past, researchers are able to develop theories that may
explain historical events and patterns. These theories lead to
hypotheses, which are evaluated in terms of additional
historical data that are collected. Historical researchers may
use qualitative methods (e.g., examining historical
documents, using insight and judgment to identify themes) or
quantitative methods (e.g., counting certain types of
statements made in historical documents).

TOPIC REVIEW
1. Suppose a researcher administered an intelligence test to
young children each year for five years in order to study
changes in intelligence over time. The researcher was
conducting what type of study?
2. Is the study in Question 1 experimental?
3. If a researcher conducts a poll to estimate public support
for free childcare for mothers on welfare, the researcher is
conducting what type of nonexperimental study?
4. A researcher determined the degree of relationship
between vocabulary scores and reading comprehension
scores. The researcher was conducting what type of
nonexperimental study?
5. According to this topic, what is a distinctive feature of
quantitative research?
6. How is most published qualitative research collected?

DISCUSSION QUESTIONS
1. Name a topic in your field of study that you might explore
with a nonexperimental study. Which type of
nonexperimental study would be most appropriate for your
topic?
2. Think of a survey in which you were asked to serve as a
participant. (You may have been sent a questionnaire in the
mail, such as a consumer satisfaction survey, or you
may have been contacted in person or by phone.) Did you
cooperate and respond? Why? Why not?
3. Name two quantitative variables that might be studied
through the use of correlational research.
4. Suppose someone prepared a list of educational events
and their dates of occurrence in the past 100 years. Would
the list be an example of good historical research? Explain.

RESEARCH PLANNING
Consider the differences in the types of nonexperimental
research discussed in this topic.
Which most fits with the study you would like to pursue and
why? Does your research question clearly fit into one type?
Explain the basis for your choice.

NOTES
1. Characteristics of good samples for quantitative research
are explored in detail in Topics 25, 26, 31, and 32
in Part 4 of this book. Considerations in sampling for
qualitative research are described in Topics 29 and
33 in Part 4 of this book.
2. Types of variables are described in Part 3, Topics 21, 22
and 23.
3. This relates to “validity,” which is explored in Part 5 of this
book. Correlational studies employ a statistic called a
correlation coefficient, which is described in Topic 67.

Good luck!