Practical Research 2: Quantitative Methods

Study Notes

Practical Research 2: Quantitative Research Methods

Quantitative research uses numerical data to identify trends, correlations, and causality between variables. It employs statistical analysis to draw conclusions about a population based on a sample.
It's characterized by structured procedures, measurable variables, and the use of statistical tools to objectively analyze data.
Different approaches to quantitative research exist. Key characteristics include:
- Controlled experiments: Researchers manipulate one or more variables (independent) to observe their effect on another variable (dependent).
- Surveys: Collecting data through questionnaires or structured interviews to describe attitudes, behaviors, or characteristics of a population.
- Observational studies: Observing and recording behaviors or phenomena without manipulating variables. These can be further categorized as structured (e.g., a checklist) or unstructured (field observations).
- Analyzing pre-existing data: Using data previously collected for a different purpose as part of a current research investigation.

Types of Variables

Independent variable (IV): The variable that is manipulated or controlled by the researcher to observe its effect on the dependent variable.
Dependent variable (DV): The variable that is measured to determine the effect of the independent variable.
Extraneous variable: A variable that has an unwanted influence on the relationship between the IV and DV; researchers strive to control these.
Control variables: Variables that are kept constant throughout the study to isolate the effect of the IV on the DV. Examples include age, gender, socioeconomic status.
Categorical variables: Variables that can be grouped into categories (e.g., gender, ethnicity, treatment group). These can be further divided into nominal (e.g., colors, social groups) and ordinal (e.g., Likert scales, socioeconomic levels).
Continuous variables: Variables that can take on any value within a given range (e.g., height, weight, temperature). This includes interval (e.g., temperature) and ratio (e.g., weight).

Research Design Structures

Experimental design (true experimental): Involves manipulation of an independent variable under controlled conditions to measure its effect on a dependent variable. Essential characteristics include random assignment, manipulation of the IV, and careful control of extraneous variables.
Quasi-experimental design: Similar to true experiments but lacks random assignment or complete control over extraneous variables.
Non-experimental research: Does not involve manipulation of variables. This type of research design primarily describes and explores relationships. Examples include correlational studies and descriptive studies.
Correlational studies: Examine the relationship between two or more variables without manipulating them. Correlation does not equal causation. The focus is on identifying patterns in the data.
Descriptive research: Aims to describe the characteristics of a population or phenomenon without attempting to establish causality. Focuses on frequency, distribution, and characteristics of a particular variable within a specific population.

Key Considerations in Quantitative Research

Sampling methods: Selecting a representative sample from a larger population to ensure generalizability of findings to the broader population. Random sampling is the gold standard, but stratified and cluster sampling are also frequently used.
Data collection instruments: Developing or selecting reliable and valid instruments to collect data, like questionnaires, structured observations, and standardized tests.
Data analysis techniques: Employing appropriate statistical and analytic techniques, such as t-tests, correlations, regressions, to analyze collected data and draw conclusions.
Ethical considerations: Ensuring the protection of participants' rights and welfare, including obtaining informed consent, maintaining confidentiality, and minimizing potential harm.
Validity and reliability: Ensuring that the research measures what it is intended to measure (validity) and that the measurements are consistent and dependable (reliability).

Description

Explore the key concepts of quantitative research methods. This quiz highlights controlled experiments, surveys, and observational studies, focusing on how numerical data is used to identify trends and correlations. Test your understanding of statistical analysis techniques used in this research approach.