Experimental Research Design

Study Notes

An experimental research design involves manipulating one or more independent variables and measuring their effect on one or more dependent variables.
This type of design is the most effective method for testing a hypothesis, as it allows for the investigation of causal relationships between variables.
Three basic principles of experimental design are:
- The principle of replication: repeating the experiment multiple times to increase statistical accuracy.
- The principle of randomization: randomizing the assignment of subjects to treatment groups to eliminate bias.
- The principle of local control: ensuring that controls are part of the test factors.

An analytical research design aims to understand phenomena by discovering and measuring causal relationships among them.

A research design is a plan that outlines the specifics of a research project, including what, where, when, how much, and by what means.
It includes a plan for the time and cost budgets, as most studies are conducted under these constraints.

Exploratory research designs:
- Also known as formulative research studies.
- Aim to understand a problem for more precise investigation or to develop working hypotheses.
- Emphasize the discovery of ideas and insights.
- Methods include:
  - Literature survey
  - Experience survey
  - Analysis of "insight-stimulating" examples
Descriptive and diagnostic research designs:
- Descriptive research studies describe the characteristics of a particular individual or group.
- Diagnostic research studies determine the frequency with which something occurs or its association with something else.
Hypothesis-testing research designs:
- Also known as experimental studies.
- Test hypotheses of causal relationships between variables.
- Require procedures that reduce bias, increase reliability, and permit drawing inferences about causality.

An indirect approach disguises the true purpose of the project.
Projective techniques are unstructured, indirect forms of questioning that encourage respondents to project their underlying motivations, beliefs, attitudes, or feelings.

A quantitative research design seeks to quantify data and applies statistical analysis.
Involves generating data in quantitative form, which can be subjected to rigorous quantitative analysis in a formal and rigid fashion.
Aims to:
- Describe variables
- Examine relationships among variables
- Determine cause-and-effect interactions between variables

An experiment is an investigation in which a factor or variable under test is isolated and its effect(s) measured.
A survey is a method of securing information concerning a phenomenon under study from all or a selected number of respondents.

Primary data: collected afresh and for the first time.
Secondary data: collected by someone else and already passed through statistical process.
Methods of collecting primary data:
- Observation
- Interview method
- Through questionnaires
- Through schedules

A popular method of data collection, particularly in large-scale inquiries.
Questionnaires are sent to respondents with a request to answer the questions and return the questionnaire.
Types of questionnaires:
- Structured questionnaires: have definite, concrete, and pre-determined questions.
- Unstructured questionnaires: have a general guide on the type of information to be obtained, but exact question formulation is left to the interviewer.
Characteristics of structured questionnaires:
- Standardized questions
- Closed or open-ended questions
- Limited space for respondents' comments
Characteristics of unstructured questionnaires:
- General guide on the type of information to be obtained
- Exact question formulation is left to the interviewer
- Replies are taken down in the respondent's own words.