1. What is quantitative research?
1.1. Objectivism
1.1.1. Positivist epistemology
1.1.1.1. Deductive approach
1.1.1.1.1. Testing hypotheses
1.2. Collecting measurable data
1.2.1. Understand patterns, relationships and trends
1.2.2. Statistical analysis and mathematical models
1.3. Design
1.3.1. Experimental
1.3.1.1. manipulation of an independent variable to observe its effects on a dependent variable
1.3.2. Quasi experimental
1.3.2.1. do not involve manipulation of the independent variable but still involve comparison of groups
1.3.3. Descriptive
1.3.3.1. used to gather information about the characteristics of a population, but do not involve manipulation or comparison
1.4. Data
1.4.1. Sources
1.4.1.1. Surverys
1.4.1.2. Questionnaires
1.4.1.3. Experiments
1.4.2. Systematic and standardised approach
1.4.2.1. Reduce 'error'
1.5. Analysis
1.5.1. Descriptive
1.5.1.1. summarise data
1.5.2. Inferential
1.5.2.1. make predictions and test hypotheses
1.5.3. Regression
1.5.3.1. examine relationships
1.6. Summary
1.6.1. Research question:
1.6.1.1. A clear and well-defined research question guides the entire research process and provides a framework for the analysis.
1.6.2. Hypothesis:
1.6.2.1. A hypothesis is a statement about the expected relationship between variables that can be tested using quantitative methods.
1.6.3. Study design:
1.6.3.1. The study design outlines the methods used to collect and analyse data, including the sampling strategy, data collection instruments, and statistical methods.
1.6.4. Sample selection:
1.6.4.1. The sample must be representative of the population of interest and large enough to ensure the validity of the results.
1.6.5. Data collection:
1.6.5.1. The data must be collected in a systematic and standardized manner to ensure its accuracy and reliability.
1.6.6. Data analysis:
1.6.6.1. The data must be analysed using appropriate statistical techniques, such as descriptive statistics, inferential statistics, and regression analysis.
1.6.7. Validity and reliability:
1.6.7.1. The validity and reliability of the results are dependent on the quality of the data and the robustness of the statistical methods used.
2. What makes a good quantitative study?
2.1. Validity
2.1.1. Internal validity
2.1.1.1. the extent to which a study measures what it is intended to measure and accurately reflects the true relationship between variables
2.1.1.2. Threats to internal validity e.g.
2.1.1.2.1. selection bias,
2.1.1.2.2. maturation,
2.1.1.2.3. history,
2.1.1.2.4. testing,
2.1.1.2.5. instrumentation,
2.1.1.2.6. regression to the mean,
2.1.1.2.7. experimenter effects
2.1.2. External validity
2.1.2.1. the degree to which the findings of a study can be applied beyond the specific sample and conditions of the study
2.1.2.1.1. Ecological validity:
2.1.2.1.2. Population validity:
2.1.2.1.3. Historical validity:
2.1.2.2. Threats to external validity
2.1.2.2.1. Selection bias:
2.1.2.2.2. Limited sample size:
2.1.2.2.3. Reactive effects:
2.1.2.2.4. Artefacts:
2.1.2.2.5. Specificity of the intervention:
2.1.2.2.6. Temporal specificity:
2.2. Reliability
2.2.1. the consistency and stability of the results of a study over time and across different measurements or conditions
2.2.1.1. an essential part of a study's validity
2.2.1.1.1. Can be reliable and not valid but cannot be valid if not reliable
2.2.2. Types of reliability
2.2.2.1. Test-retest reliability:
2.2.2.1.1. This measures the stability of results over time, by repeating the study on the same participants at different points in time.
2.2.2.2. Inter-rater reliability:
2.2.2.2.1. This measures the consistency of results between different raters or evaluators, by having multiple raters evaluate the same data.
2.2.2.3. Internal consistency reliability:
2.2.2.3.1. This measures the consistency of results within a single measurement or test, by assessing the consistency of the results within a single administration of a test.
2.2.2.4. Split-half reliability:
2.2.2.4.1. This measures the consistency of results between two halves of a test, by splitting a test into two parts and comparing the results.