-QUANTITATIVE RESEARCH-

Quantitative Research (Part 4)

Causal-Comparative Research

>to find out the cause or consequences of differences that already exist between or among group of individuals

>the group difference variable is either:

            >a variable that cannot be manipulated (ethnicity) or

            >a variable that cannot be manipulated due to several reasons (teaching style)

>disadvantages:

            >lack of control (threats)

Steps Involved in Causal-Comparative Research

>problem formulation

>sample selection

>instrumentation

>design

            >the basic causal-comparative design

Threats to Internal Validity in Causal-Comparative Research

>subject characteristics

            >procedures:

                        a. Matching of Subjects

                        b. finding or creating homogeneous subgroups

                        c. statistical matching

Evaluating Threats to Internal Validity in Causal-Comparative Studies

>Subject characteristics

            >SES, gender, ethnicity, marketable job skills

>Location

>Instrumentation

            >Instrument Decay

            >Data Collector Characteristics

            >Data Collector Bias

>Other treats

            >implementation, history, maturation, attitudinal and regression