Selection Bias
Definition
A distortion that arises when the group being studied is not a random sample of the wider population; in Neighbourhood Watch research, streets that organise a scheme differ systematically from streets that do not, which can make the scheme look more effective than it is.
Related terms
- Beat System
- The division of a police jurisdiction into fixed local patrol areas, each assigned to an officer expected to build familiarity with residents;...
- Community-Based Crime Prevention
- Any prevention approach that relies on residents themselves, rather than police or situational design alone, to reduce crime and disorder in a...
- Community Policing
- A policing model that builds sustained partnerships between officers and residents through foot patrols, neighbourhood liaison, and joint problem identification. Emphasises prevention...
- Exclusionary Surveillance
- Watching or reporting that treats unfamiliar people, particularly on the basis of race, age, or class, as inherently suspicious, turning a crime-reporting...
- Gatekeeper
- A person or institution, such as a prison superintendent, police officer or community elder, who controls a researcher's access to a setting...
- Hidden Population
- A group with no enumerable sampling frame and a stigmatised or illegal status that gives its members an incentive to avoid being...
- Neighbourhood Watch
- A scheme in which residents of a street or small area agree to watch out for suspicious activity, report it to the...
- Respondent-Driven Sampling
- A variant of chain referral, developed by Douglas Heckathorn in 1997, that tracks who recruited whom and each respondent's network size so...
- Sampling Frame
- The list or description of all units from which the sample can be drawn. Any unit not on the frame cannot be...
- Snowball Sampling
- A chain-referral technique in which each recruited respondent is asked to name or introduce others who share the trait the study is...
Explained in these topics
- Neighbourhood Watch and Resident-Led Crime Prevention
- Sampling and Fieldwork with Hard-to-Reach PopulationsA systematic difference between the people who end up in a sample and the wider population they are meant to represent, commonly introduced in chain-referral s...