Quantitative Research
Quantitative research is an objective, systematic empirical investigation of observable phenomena through the use of computational techniques. It highlights numerical analysis of data hoping that the numbers yield unbiased results that can be generalized to some larger population and explain a particular observation. Simply, quantitative research is concerned with numbers and its relationship with events.
CHARACTERISTICS are @@Objective and Reliable, Clearly defined research questions, structured research instruments, numerical data, large sample sizes@@ & future outcomes.
Quantitative research puts emphasis on proof rather than discovery.
STRENGTHS: Objective, Uses Statistical Techniques, Real and Unbiased, Numerical data can be analyzed easily, replicable, useful for testing the results gained by a series of qualitative experiments, leading to a final answer
WEAKNESSES: Requires a large number of respondents, costly, context and other information that provide a richer understanding of observed trends and patterns can get lost, errors in the measurement or modeling or the omission of data can easily lead to the misinterpretation of results, emphasis on generalizability and trends hinders the deeper examination of nuanced factors that affect specific cases, & some tools utilized may yield limited or even inaccurate information.
What does a Research Design look like?
A blueprint or detailed plan for conducting a study, purpose, review of literature and framework provide the basis for the design.
1. EXPERIMENTAL RESEARCH DESIGN. This allows the researcher to control the situation. In doing so, it allows the researcher to answer the question, “What causes something to occur?” This kind of research also allows the researcher to identify cause and effect relationships between variables and to distinguish placebo effects from treatment effects. Further, this research design supports the ability to limit alternative explanations and to infer direct causal relationships in the study; the approach provides the highest degree level of evidence for single studies.
A. PRE-EXPERIMENTAL DESIGN. A type of research apply to experimental design that with @@least internal validity@@. One type of pre-experiment, the simple group, pre-test-post-test design, measures the group two times, before and after the intervention.
Instead of comparing the pretest with the posttest within one group, the posttest of the treated groups is compared with that of an untreated group. Measuring the effect as the difference between groups marks this as between-subjects design. Assuming both groups experienced the same time-related influences, the comparison group feature should protect this design from the rival explanations that threaten the within-subject design.
Two classes of experimental design that can provide better internal validity than pre-experimental designs are: quasi-experimental and true experimental design (Dooly, 1999).
B. QUASI – EXPERIMENTAL DESIGN. In this design, the researcher can collect more data, either by scheduling more observations or finding more existing measures. Quasi-experimental design involves selecting groups, upon which a variable is tested, without any random pre-selection processes. For example, to perform an educational experiment, a class might be arbitrarily divided by alphabetical selection or by seating arrangement. The division is often convenient and, especially in an educational situation, causes as little disruption as possible. After this selection, the experiment proceeds in a very similar way to any other experiment, with a variable being compared between different groups, or over a period of time.
There are two types of quasi-experimental design, these are:
a. Non-Equivalent Control Group. This refers to the chance failure of random assignment to equalize the conditions by converting a true experiment into this kind of design, for purpose of analysis.
b. Interrupted Time Series Design. It employs multiple measures before and after the experimental intervention. It differs from the single-group pre-experiment that has only one pretest and one posttest. Users of this design assume that the time threats such as history or maturation appear as regular changes in the measures prior to the intervention.
C. TRUE-EXPERIMENTAL DESIGN. It controls for both time-related and group-related threats. Two features mark true experiments: two or more differently treated groups; and random assignment to these groups. These features require that the researchers have control over the experimental treatment and the power to place subjects in groups.
True experimental design employs both treated and control groups to deal with time-related rival explanations.
A control group reflects changes other than those due to the treatment that occur during the time of the study. Such changes include effects of outside events, maturation by the subjects, changes in measures and impact of any pre-tests.
True experimental design offers the highest internal validity of all the designs. Quasi-experimental design differs from true experimental design by the absence of random assignment of subjects to different conditions. What quasi-experiments have in common with true experiments is that some subjects receive an intervention and provide data likely to reflect its impact.
2. NON-EXPERIMENTAL DESIGN. In this kind of design, the researcher observes the phenomena as they occur naturally and no external variables are introduced. In this research design, the variables are not deliberately manipulated nor is the setting controlled. Researchers collect data without making changes or introducing treatments. This may also called as DESCRIPTIVE RESEARCH DESIGN because it is only one under non-experimental design.
DESCRIPTIVE RESEARCH DESIGN’s main purpose is to observe, describe and document aspects of a situation as it naturally occurs and sometimes to serve as a starting point for hypothesis generation or theory development.
The types of descriptive design are as follows:
A. SURVEY. It is used to gather information from groups of people by selecting and studying samples chosen from a population. This is useful when the objective of the study is to see general picture of the population under investigation in terms of their social and economic characteristics, opinions, and their knowledge about the behavior towards a certain phenomenon.
B. CORRELATIONAL. It is conducted by researchers whose aim would be to find out the direction, associations and/or relationship between different variables or groups of respondents under study. Correlational Research has three types, these are:
a. Bivariate Correlational Studies – It obtains score from two variables for each subject, and then uses them to calculate a correlation coefficient. The term bivariate implies that the two variables are correlated (variables are selected because they are believed to be related).
b. Prediction Studies – It uses correlation coefficient to show how one variable (the predictor variable) predicts another (the criterion variable).
c. Multiple Regression Prediction Studies – All variables in the study can contribute to the over-all prediction in an equation that adds together the predictive power of each identified variable.
C. EX-POST FACTO or CAUSAL-COMPARATIVE. This kind of research derives conclusion from observations and manifestations that already occurred in the past and now compared to some dependent variables. It discusses why and how a phenomenon occurs.
D. COMPARATIVE. It involves comparing and contrasting two or more samples of study subjects on one or more variables, often at a single point of time. Specifically, this design is used to compare two distinct groups on the basis of selected attributes such as knowledge level, perceptions, and attitudes, physical or psychological symptoms.
E. NORMATIVE. It describes the norm level of characteristics for a given behavior. For example: If you are conducting a research on the study habits of the high school students you are to use the range of score to describe the level of their study habits. The same true is when you would want to describe their academic performance.
F. EVALUATIVE. It is a process used to determine what has happened during a given activity or in an institution. The purpose of evaluation is to see if a given program is working, an institution is successful according to the goals set for it, or the original intent was successfully attained. In other words, in evaluation judgments can be in the forms of social utility, desirability, or effectiveness of a process. For example, we can cite here a situation. In evaluation study, it will not just be considering the performance of the students who were taught under modular instruction; instead, it is the rate of progress that happened among the students who were exposed to modular instruction.
G. METHODOLOGICAL. In this approach, the implementation of a variety of methodologies forms a critical part of achieving the goal of developing a scale-matched approach, where data from different disciplines can be integrated.