Measurement, Scaling and Sampling

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Measurement, Scaling and Sampling

Published by: Anu Poudeli

Published date: 14 Jul 2023

Measurement, Scaling and Sampling

In research and data analysis, measurement, scaling, and sampling are critical ideas. They are critical to the reliability, validity, and generalizability of study findings. Let's take a closer look at each of these ideas:

Measurement

Measurement is the practice of assigning numbers or symbols to qualities or attributes of objects or events based on predefined rules. It is required for quantitative variables and systematic data collection. There are various levels of measurement, such as:

  • Variables are classified into various groups or categories at this level, with no intrinsic order. Gender (male, female) and marital status (single, married, divorced) are two examples.
  • ordinal variables have categories that can be sorted or ranked, but the intervals between categories are not always equal. A Likert scale, for example, is used to assess attitudes (e.g., strongly disagree, disagree, neutral, agree, highly agree).
  • Interval: Interval variables have ordered categories with equal intervals between them, but no meaningful zero point. Temperatures in Celsius or Fahrenheit are two examples.

 

  • Ratio variables have all of the qualities of interval variables, as well as a meaningful zero point. Height, weight, and money are a few examples.
  • Selecting the appropriate level of measurement is critical for selecting relevant statistical analyses and effectively interpreting results.

Scaling

Scaling is the practice of giving values to measurements in order to indicate the relative magnitude of the variables under consideration. It enables data comparison and analysis for researchers. Depending on the type of data and the study aims, many scaling strategies are used:

  • Likert Scaling: This technique assigns numerical values to responses on a Likert scale, which is a regularly used attitude and opinion assessment scale.

 

  • Thurstone Scaling: This method entails developing a set of statements or items relevant to a specific concept and having judges rank them based on their perceived intensity or relevance.
  • Guttman Scaling: Guttman scaling, also known as cumulative scaling, entails generating a succession of assertions that form a hierarchical scale, with agreement with one statement implying agreement with all claims below it.
  • Semantic Differential Scaling: To capture respondents' impressions or attitudes, this technique involves ranking objects or concepts on bipolar scales (e.g., good-bad, strong-weak).

 

  • Scaling strategies aid researchers in quantifying subjective constructs and facilitating statistical analyses and result interpretation.

Sampling

Sampling is the process of picking a group of individuals or units from a larger population for research purposes. Because collecting data from a whole population is impractical, expensive, or impossible, sampling allows researchers to make predictions about the population based on the data collected. Among the most prevalent sampling methods are:

  • Simple random sampling means that every member of the population has an equal chance of being chosen. When the population is homogeneous, this strategy ensures representativeness.
  • Stratified Sampling: The population is separated into homogeneous subgroups (strata), from which random samples are collected. This strategy ensures that each subgroup is represented.

 

  • Cluster sampling involves dividing the population into clusters and selecting a random sample of clusters. Data is gathered from all individuals in the chosen clusters. This strategy is effective when there are geographical or organizational divisions.
  • Convenience sampling is when researchers choose people who are freely available or easily accessible. While this strategy is easy, it has the potential to increase sample bias and limit generalizability.
  • Purposive sampling is when researchers choose participants based on specific criteria related to the study subject. This approach is frequently employed in qualitative research or when examining a specific subgroup.
  • The sampling techniques used should be determined by the research objectives, available resources, and the desired level of representativeness and generalizability.


In conclusion, measurement, scaling, and sampling are critical ideas in research and data analysis. Proper measurement and scaling procedures ensure precise quantification and comparison of variables, whereas suitable sampling methods enable researchers to draw valid conclusions about populations based on a subset of data.