Measurement and Units of Analysis
27 Summary
This chapter has focused on understanding how a researcher moves from identifying concepts to conceptualizing them and then to operationalizing them in a research project. Each step becomes more specific than the previous. The researcher begins with a general interest, identifies a few concepts that are essential for studying the area of interest, works to define those concepts, and then spells them out precisely. As discussed earlier in the chapter, the researcher next must decide how to measure those concepts. In other words, the researcher’s focus becomes narrower and narrower as s/he moves from a general interest to operationalization.
Key Takeaways
- Reliability in measurement is about consistency. Validity in Measurement is about social agreement;
- Internal validity means that the experiment actual tests what it seeks to test, while external validity means that the study is generalizable to other situations and contexts;
- A variable refers to a grouping of several characteristics. Attributes are those characteristics.
- Nominal level of measurement has attributes that meet the criteria of exhaustiveness and mutual exclusivity. Ordinal level measurement can be rank ordered, though we cannot calculate a mathematical distance between those attributes. Interval level measurement meets all criteria if the two preceding levels, plus the distance between attributes is known to be equal. Ratio level measurement has attributes that are mutually exclusive and exhaustive, attributes can be rank ordered, the distance between attributes is equal, and attributes have a true zero point.
- Unit of analysis is the entity that you wish to be able to say something about at the end of your study, probably what you’d consider to be the main focus of your study. A unit of observation is the item (or items) that you actually observe. measure, or collect in the course of trying to learn something about your unit of analysis
- An independent variable is one that causes another. It is the variable that is manipulated by the researcher in order to measure the difference in the outcome or the dependent variable. A dependent variable is one that is caused by another.
- An extraneous variable may compete with the independent variable in explaining the outcome.
- A rival plausible explanation (RPE) is an alternative factor that may account for the results you observed in your research, other than what you might have been expecting to the idea that respondents will try to answer.
References
Explore Psychology. (2019). What is an extraneous variable. Retrieved from https://www.explorepsychology.com/what-is-an-extraneous-variable/
Palys, T., & Atchison, C. (2014). Research decisions: Quantitative, qualitative, and mixed methods approaches. Toronto, Canada: Nelson Education Ltd.
Schmitz, A. (2012). Principles of sociological inquiry; Qualitative and quantitative methods. Washington, DC: Saylor Academy. Retrieved from https://www.saylor.org/site/textbooks/Principles%20of%20Sociological%20Inquiry.pdf
