Assess Your Research Methods Knowledge with this Construct

Fundamentals of Research Methods: Constructs, Variables, Measurement Properties, Questionnaires, Validity, and Reliability

• Constructs are abstract concepts used to describe things not easily observable/measured.
• Variables are quantifiable and directly measurable, and a measure of variables is representative of the construct.
• Independent (predictor) variables are expected to have an impact/influence/effect on the dependent (outcome) variable being measured.
• The process involves identifying, defining, and deriving a score on variables reflecting the construct.
• Measurement properties include magnitude, intervals, and rational zero, which are used to analyze data from nominal, ordinal, interval, and ratio scales.
• Categorical and continuous data are two types of data that can be analyzed using different measurement properties and scales.
• Questionnaires are an efficient way of gathering data, but common errors include complicated or frustrating questions, double-barrelled questions, and biased or loaded questions.
• Validity refers to being accurate and involves conceptual, construct, convergent, discriminant, content, predictive, internal, and external validity.
• Reliability refers to consistency and involves test-retest, inter-rater, and internal reliability, as well as the law of big numbers and Chronbach’s alpha.
• Chronbach’s alpha is a statistic used to measure the internal consistency/reliability of a set of items, and coefficients range from 0 to 1.
• An alpha of .70+ is considered adequate, while anything below 0.5 is poor.
• An alpha of .65 is around the good mark but could still be improved/questioned/noted as a limitation.

Key Concepts in Research Methodology

• The scientific method involves observations, hypothesis testing, data analysis, and conclusion drawing.
• Constructs are abstract concepts, while variables are quantifiable aspects that represent constructs.
• Different scales of measurement have different measurement properties and require different methods of analysis.
• Questionnaires are an efficient way of gathering data, but common errors in design should be avoided.
• Validity and reliability are important considerations in research design.
• Experimental design involves manipulating the independent variable to investigate causal relationships.
• Generalization involves applying study results to a larger target group, and random selection is used to minimize selection bias.
• Repeated measure design involves measuring the same participants on multiple occasions, and controlling for order effects and progressive error is important.
• Non-experimental designs are preferred for studying relations between variables or when it is impractical or unethical to manipulate variables.
• Qualitative research designs focus on exploring and understanding phenomena.
• Threats to validity include history effects, maturation effects, and participant reaction bias, which can be controlled through various strategies.
• Central tendency and variability measures help describe the distribution of scores in a sample, and correlation coefficients can be used to quantify relationships between variables.