Research Methods – Exam Preparation
Week 1
Induction vs. Deduction
- Induction means you first observe reality, after which you try to order the results and
based on this you describe a pattern (formulate a theory)
- Deduction means you first think about patterns in reality (‘theorize’) after which you
check (do research) whether the theory makes sense in reality (in the empirical world).
Design for Research
- Cross-Sectional Design: In a cross-sectional study, data is collected at a single point in
time from different individuals or groups
o Benefits: high reliability and external validity
- Downsides: lower internal validity
- Longitudinal Design: Longitudinal studies involve collecting data from the same
individuals or groups over an extended period
o Benefits: internal validity better than cross sectional
o Downsides: lower reliability and external validity than cross-sectional design
- Experimental Design: Experimental designs involve manipulating one or more
variables to assess their causal effects on another variable
o Benefits: high internal validity
o Downsides: lower reliability and external validity
Confidence Interval vs. Point Estimate
The reason for calculating a confidence interval rather than a point estimate is because we
want to know the estimate of the likely range in which we can be reasonably sure that the true
population will lie.
, Confidence Intervals: Means vs. Proportions
Level of measurement:
- Ordinal and Interval à Mean
- Nominal à Proportion
Confidence Interval: How to Answer
Given a 95% confidence interval (i.e., 0.2115; 0,2543), what does this mean?
This means that that interval contains the true population value 95% of the times. That is, we
can be 95% confident that, i.e. the percentage of the Dutch population that would vote to leave
the EU, lies between 21.15% and 25.43%.
Is it more or less precise than the 99% confidence interval? Why?
The 95% confidence interval is more precise than the 99% percent one, since the 99%
confidence interval is wider than the 95% one. This means that the 99% interval includes more
values that would be excluded if we were only 95% confident in the values we found.
Note: there’s an exchange between certainty and precision
- The more certain (i.e., 99%), the less precise (i.e., 95%)
Week 2
Regression Equation
𝑦! = 𝑏" + 𝑏# 𝑥!
Regression Coefficient: How to Answer
Give a substantive interpretation of the regression coefficient of, i.e., age (0.006), and its
significance.
This value represents the increase (or decrease) in y for every increase of 1 unit in x.
- Interpretation of the Coefficient:
The coefficient of 0.006 suggests that for every one-year increase in age, there is a
corresponding increase of 0.006 in the predicted value of the self-identified political
position on the scale from 0 to 10.
Week 1
Induction vs. Deduction
- Induction means you first observe reality, after which you try to order the results and
based on this you describe a pattern (formulate a theory)
- Deduction means you first think about patterns in reality (‘theorize’) after which you
check (do research) whether the theory makes sense in reality (in the empirical world).
Design for Research
- Cross-Sectional Design: In a cross-sectional study, data is collected at a single point in
time from different individuals or groups
o Benefits: high reliability and external validity
- Downsides: lower internal validity
- Longitudinal Design: Longitudinal studies involve collecting data from the same
individuals or groups over an extended period
o Benefits: internal validity better than cross sectional
o Downsides: lower reliability and external validity than cross-sectional design
- Experimental Design: Experimental designs involve manipulating one or more
variables to assess their causal effects on another variable
o Benefits: high internal validity
o Downsides: lower reliability and external validity
Confidence Interval vs. Point Estimate
The reason for calculating a confidence interval rather than a point estimate is because we
want to know the estimate of the likely range in which we can be reasonably sure that the true
population will lie.
, Confidence Intervals: Means vs. Proportions
Level of measurement:
- Ordinal and Interval à Mean
- Nominal à Proportion
Confidence Interval: How to Answer
Given a 95% confidence interval (i.e., 0.2115; 0,2543), what does this mean?
This means that that interval contains the true population value 95% of the times. That is, we
can be 95% confident that, i.e. the percentage of the Dutch population that would vote to leave
the EU, lies between 21.15% and 25.43%.
Is it more or less precise than the 99% confidence interval? Why?
The 95% confidence interval is more precise than the 99% percent one, since the 99%
confidence interval is wider than the 95% one. This means that the 99% interval includes more
values that would be excluded if we were only 95% confident in the values we found.
Note: there’s an exchange between certainty and precision
- The more certain (i.e., 99%), the less precise (i.e., 95%)
Week 2
Regression Equation
𝑦! = 𝑏" + 𝑏# 𝑥!
Regression Coefficient: How to Answer
Give a substantive interpretation of the regression coefficient of, i.e., age (0.006), and its
significance.
This value represents the increase (or decrease) in y for every increase of 1 unit in x.
- Interpretation of the Coefficient:
The coefficient of 0.006 suggests that for every one-year increase in age, there is a
corresponding increase of 0.006 in the predicted value of the self-identified political
position on the scale from 0 to 10.
