Measurement of Constructs (Levels of Measurement: Levels of measurement,…
Measurement of Constructs
Conceptualization is the mental process by which fuzzy and imprecise constructs (concepts) and their constituent components are defined in concrete and precise terms.
Unidimensional constructs are those that are expected to have a single underlying dimension.
Multidimensional constructs consist of two or more underlying dimensions. For instance, if we conceptualize a person’s academic aptitude as consisting of two dimensions – mathematical and verbal ability – then academic aptitude is a multidimensional construct.
Operationalization refers to the process of developing indicators or items for measuring these constructs.
The combination of indicators at the empirical level representing a given construct is called a variable
Also each indicator may have several attributes (or levels) and each attribute represent a valu
A reflective indicator is a measure that “reflects” an underlying construct.
A formative indicator is a measure that “forms” or contributes to an underlying construct.
Levels of Measurement: Levels of measurement, also called rating scales, refer to the values that an indicator can take (but says nothing about the indicator itself).
Interval scales are those where the values measured are not only rank-ordered, but are also equidistant from adjacent attributes.
Ordinal scales are those that measure rank-ordered data, such as the ranking of students in a class as first, second, third, and so forth, based on their grade point average or test scores.
Nominal scales, also called categorical scales, measure categorical data. These scales are used for variables or indicators that have mutually exclusive attributes
Ratio scales are those that have all the qualities of nominal, ordinal, and interval scales, and in addition, also have a “true zero” point (where the value zero implies lack or nonavailability of the underlying construct).
Binary scales. Binary scales are nominal scales consisting of binary items that assume one of two possible values, such as yes or no, true or false, and so on.
Likert scale. Designed by Rensis Likert, this is a very popular rating scale for measuring ordinal data in social science research.
Semantic differential scale. This is a composite (multi-item) scale where respondents are asked to indicate their opinions or feelings toward a single statement using different pairs of adjectives framed as polar opposites.
Guttman scale. Designed by Louis Guttman, this composite scale uses a series of items arranged in increasing order of intensity of the construct of interest, from least intense to most intense.
Scaling: is a branch of measurement that involves the construction of measures by associating qualitative judgments about unobservable constructs with quantitative, measurable metric units.
Likert’s summative scaling method. The Likert method, a unidimensional scaling method developed by Murphy and Likert (1938), is quite possibly the most popular of the three scaling approaches
Thurstone’s equal-appearing scaling method. Louis Thurstone. one of the earliest and most famous scaling theorists, published a method of equal-appearing intervals in 1925. This method starts with a clear conceptual definition of the construct of interest.
The outcome of a scaling process is a scale, which is an empirical structure for measuring items or indicators of a given construct.
Guttman’s cumulative scaling method. Designed by Guttman (1950), the cumulative scaling method is based on Emory Bogardus’ social distance technique, which assumes that people’s willingness to participate in social relations with other people vary in degrees of intensity, and measures that intensity using a list of items arranged from “least intense” to “most intense”.
Index: composite score derived from aggregating measures of multiple constructs (called components) using a set of rules and formulas.
socio-economic status (SES), also called the Duncan socioeconomic index (SEI). This index is a combination of three constructs: income, education, and occupation. Income is measured in dollars, education in years or degrees achieved, and occupation is classified into categories or levels by status.
Though indexes and scales yield a single numerical score or value representing a construct of interest, they are different in many ways
Typologies: measures of two or more constructs to create a set of categories or type