Quantitative Versus Qualitative Research Methods Comparison
Elements of Investigation: Quantitative vs. Qualitative
1. Environment (MARCO)
- Quantitative: Can be developed in a natural environment or a closed laboratory.
- Qualitative: In contact with the object being studied, in a natural setting.
2. Design Structure
- Quantitative: Requires a fixed design established a priori (in advance).
- Qualitative: Has an emergent design; it is not fixed in advance.
3. Goals and Flexibility
- Quantitative: Techniques are pre-set, aiming for technical flexibility.
- Qualitative: The reality of everyday life leads to changes in techniques; it is more flexible.
4. Theoretical Framework
- Quantitative: Always starts from a theoretical framework and previous assumptions, guiding the search for data.
- Qualitative: Theory acts as a compass, allowing for changes; they made the same experimental contrast.
5. Sampling Strategy
- Quantitative: Uses probability samples representative of the universe; subjects are selected randomly.
- Qualitative: Seeks richness of content, preferring opinion-based or non-probabilistic sampling.
6. Interpretation of Results
- Quantitative: Interpretation aims to generalize and extrapolate.
- Qualitative: Interpretation is always specific to the universal context.
7. Implementation and Replicability
- Quantitative: Seeks replication; only what is replicable, repeated (data, measurable, observable) is accepted.
- Qualitative: Seeks specific cases, contexts, and environments.
8. Study Focus (Facts/Case)
- Quantitative: Seeks social facts that are more generalized.
- Qualitative: Focuses on the environment, meaning, construction, aiming to complexify the study as much as possible.
9. Nature of Results
- Quantitative: Results are sought objectively.
- Qualitative: Results are negotiated.
10. Basics of Analysis
- Quantitative: Captures and analyzes basic social facts, especially expressed in numbers and tables.
- Qualitative: Focuses on capturing a theory that is proven through meaning.
At that time, the following errors occur:
- The selection of indicators.
- When we are collecting data.
- Coverage errors.
- Error of the sample selected in accordance with mathematical procedures: This is the only error we can control.
- Non-response error: Occurs because an individual in the sample refuses to respond.
- At the time of collection, observation, or interview.
- In the questionnaire developed (interview, etc.).
- How it is administered (mail, etc.).
- In the data transaction.
- The development of the analysis of certain procedures.
Summary of Error Types
Error (Corbett):
- Error During Operationalization: Occurs in various stages of research.
- Sampling Error: It is the only one that is controlled.
- Non-response Errors.
- Systematic Errors in Phase: Produced by the researcher or by the subject we interviewed.
- Error by Instrument: Related to the instrument we use.
Validity Measures
Content Validity: Indicators covering the specific content and meaning of it.
Criterion Validity: Correspondence with a concept and an external criterion used (e.g., comparing results with other external indicators used in other studies).
- Predictive: Relates the data with another indicator at the same moment in time.
- Simultaneous: Related to another record at the same moment in time.
Construct Validity: How the new indicator relates to the level of construction.