9: What are some core research concepts?

Glossary terms in this chapter

Policy research: Explores the impacts of different government or organizational policies and how they affect various outcomes.
Applied research: Tends to be more focused on the practical application of ideas to change the criminal justice system.
Validity: Relates to how much strength we can place in our conclusions and inferences.

Internal validity: Refers to the legitimacy of inferences we make about the causal relationship between two things. Strong internal validity in a causal relationship means changes in one thing effect or cause a change in the other.

External validity: The extent to which the findings of a study can be generalized to other situations, groups, or situations.

Reliability: Refers to whether you can consistently replicate the same results.

Generalizability: Generalizability speaks to the capacity of research to apply to other people or situations.

Sample size: Sample size is an important consideration if data are going to be sampled. Sampling means to draw a subset from a broader population. 
Population: A population is a group of individuals that share a common characteristic, such as residency of a city. These are the cases or units that comprise all individuals eligible for a study.
Eligibility pool: See population
Sample: A sample is a smaller, subset of the eligibility pool or population.
Sampling approach: The approach the researcher uses to choose the units of the population into the sample. 
Quantitative research: Involves measurable characteristics and frequently involves the use of statistical techniques to estimate how likely any observed differences between characteristics could have occurred by chance.
Positivist: Positivists lean towards the ‘science’ in ‘social science’ and favor quantitative methods to understand the laws and principles that influence human behavior and our social trends.

Mixed methods research: Mixed methods research combines quantitative and qualitative research techniques and approaches into a single study.

Surveys: Surveys are a method of asking people a range of questions about related research topics, to gain understanding of a larger population.

Closed-ended survey questions: Closed-ended survey questions limit the responses that a person can provide. The respondent can only select from the offered choices. 

Open-ended survey questions: Open-ended survey questions provide opportunity to answer and provide feedback more fully. These often comprise of open text field so respondents can type or write any answer they wish.

Dependent variable: The dependent variable is the variable being tested and measured. In evidence-based policing, it is the group, place, or population you want to impact. 

Pilot study: A preliminary project conducted at a smaller scale than the main project, so that the researcher can evaluate the feasibility and validity of the research design and methodology before embarking on the full-scale study.

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