The glossary below is compiled entirely from the open source publication Become a Problem Solving Crime Analyst in 55 Steps.
80-20 rule (also known as pareto principle) The principle that a few people or places are involved in a large proportion of events.
Distribution A description of the numerical variation in the magnitude of a problem.
Distribution, binomial A distribution used for crime count data.
Distribution, normal A bell-shaped distribution used for continuous data.
Distribution, Poisson A distribution used for discrete data where one of the outcomes is rare.
Offenders, repeat People who commit many crimes or acts of disorder (see Wolf).
Rates, crime The ratio of crimes to targets for an area. Used to control for differences in the number of targets (see Risk, crime).
Risk, crime The chance a target will be involved in a crime.
Self-containment index Proportion of crimes in an area committed by offenders living in an area.
Victim, repeat A person or place with multiple crimes or acts of disorder (see Duck).
Victimisation, repeat The process leading to repeat victims.
Virtual repeats Victimisation of targets that are very similar, though not identical (as in the case of repeat victims or places).
Activity space The nodes and routes routinely used by an offender during his/her daily activity.
Acute problems or hot spots Problems or hot spots that suddenly appear (i.e. have not been present for a long time, not chronic) (see Chronic problems or hotspots).
Attractors, Crime Areas of criminal opportunities well known to offenders.
Chronic problems or hot spots Problems or hot spots that persist for a long time (see Acute problems or hotspots).
Crime-neutral areas Areas attracting neither offenders nor targets, with adequate controls on behaviours.
Edges Boundaries between areas where people live, work, shop or seek entertainment.
Enablers, Crime Places with little regulation of behaviour.
Generators, crime Areas to which large numbers of people are attracted for reasons unrelated to criminal motivation.
Hot areas Hot spots showing neighbourhoods where crime is concentrated.
Hot dots Hot spots showing locations with high crime levels.
Hot lines Hot spots showing street segments where crime is concentrated.
Hot spots Geographic concentrations of crime.
Nodes Destination places such as home, work, shopping, entertainment and school (see Paths).
Paths Routes connecting nodes.
Place A very small area, such as an address, street corner, or block face (see Den).
Acute temporal clustering A very high concentration of crime in a small part of the 24-hour cycle.
Aoristic analysis A statistical method for determining the 24-hour rhythm of crimes when the exact time of crime commission is unknown.
Cycles Regular fluctuations in crime that correspond to daily, weekly, monthly, annual or longer changes in human activity.
Decomposing a time series Breaking down a problem into parts and plotting the time series for each part.
Focused temporal clustering Clustering of crime in distinct time ranges during 24-hour periods.
Moving average A method for reducing random fluctuation in a time series by recomputing the value for every data point based on the average of preceding time periods (see Smoothing).
Random fluctuations Short-term changes in problems caused by a large number of very small effects.
Smoothing Removing random fluctuations from a time series by using a moving average (see Moving average).
Temporal clustering Concentration of crime over 24 hours (see Acute, Diffused and Focused temporal clustering).
Trend A steady increase, decrease or stable level of crime over some period of time.
Behaviours One of two criteria for classifying problems describing aspects of harm, intent and offender–target relationships (see Environments).
Boost accounts An explanation for repeat victimisation that suggests that the rewards to the offender for the first crime encourage the offender to repeat the offence against the same victim or to tell other offenders who then attack the same victim (see Flag accounts).
CHEERS Acronym for elements defining a problem: Community, Harm, Expectation, Events, Recurring and Similarity.
CRAVED An acronym describing the characteristics of items most likely to be stolen and standing for Concealable, Removable, Available, Valuable, Enjoyable and Disposable.
Den (of iniquity) problems Problem characterised by substantial involvement of repeat places. Occurs when new potential offenders and new potential targets encounter each other in a place where management is weak.
Duck (sitting) problems Problems characterised by substantial involvement of repeat victims. Occurs when victims continually interact with potential offenders at different places, but the victims do not increase their precautionary measures and their guardians are either absent or ineffective.
Environments A criterion for classifying problems describing where the problem takes place (see Behaviours).
Facilitators Physical items, social situations or chemical substances that help offenders commit crimes or acts of disorder.
Facilitators, chemical Substances that increase offenders’ abilities to ignore risk, reward or excuses.
Facilitators, physical Things that augment offenders’ capabilities, help overcome prevention measures or incite deviancy.
Facilitators, social Situations that provide support that stimulates crime or disorder by enhancing rewards from crime, by legitimating excuses to offend or by encouraging offending.
Facilities Places that have special functions, like schools, businesses and restaurants.
Facilities, risky Facilities that are frequent sites for crime and disorder.
Flag accounts An explanation for repeat victimisation that suggests that some people are particularly vulnerable because of their occupation or their ownership of hot products (see Boost accounts).
Hot products Things that are particularly attractive as targets (see CRAVED).
Hypothesis An answer to a question about a problem that can be true or false, and may or may not be supported by evidence.
Offender A person who commits a crime or act of disorder.
Opportunity/opportunity structure Physical and social arrangements that make crime possible.
POP See Problem-oriented Policing.
Problem-oriented Policing Policing that changes the conditions that gives rise to recurring crime problems and does not simply rely on responding to incidents as they occur or forestalling them through preventive patrols.
SARA An acronym for the problem-solving process (Scanning, Analysis, Response and Assessment).
Target area An area with many potential targets (e.g. a car park for a car thief).
Target The person or thing an offender attacks, takes or harms (see Victim).
Victim A human target or the owner of stolen goods or damaged property (see Target).
Wolf (ravenous) problems Problems characterised by substantial involvement of repeat offenders. Occurs when offenders are able to locate temporarily vulnerable targets and places.
Control area A geographical area not receiving treatment but compared to a treatment area (see Control group).
Control group A group of people or an area that is similar to the treatment group or area, but does not receive treatment. Used in evaluations to control for the impact of other, non-treatment, influences on crime (see Controls (for analysis).
Controls (for analysis) Statistical and evaluation design procedures to isolate the effect of one factor on some outcome from that of others. A group of people or areas not getting a response that are compared to those receiving the response to show what would have happened to the response group, if the response group had not received the intervention (see Control Group).
Controls (on offenders) People and situations that reduce potential offenders’ willingness or capabilities to commit crimes.
CPTED See Crime Prevention Through Environmental Design.
Crime Prevention Through Environmental Design A set of principles for designing and laying-out secure buildings and public spaces.
Defiance Offenders challenge the legitimacy of prevention efforts and commit more offences rather than fewer.
Deterrence, General Communicating a public perception that the risks and penalties of offending are high, so anyone considering such behaviour will refrain.
Deterrence, Specific Communicating a perception of high risk and penalty to specific individuals so they will refrain from committing crimes.
Handler Someone who knows an offender well and who is in a position to exert some control over his or her actions.
Incapacitation Removing active offenders from society to prevent crimes that they would have committed if they were not locked up.
Intervention The response being applied to a problem (also called a treatment or response – see Response).
Manager A person who has some responsibility for controlling behaviour in a specific location.
Mechanism The process by which a response works on a problem to have an effect, or a process that causes a problem.
Owner of a problem People or institutions that are unwilling or unable to undertake prevention measures, thereby helping to create a problem.
Perceptions, offenders’ How offenders view situations and prevention measures (see also Deterrence, specific).
Provocations Physical designs or the way places are managed that provoke misconduct.
Response A term for the preventive treatment or intervention being applied (see Intervention or Treatment).
Response area See Response group.
Response group People or places receiving prevention in contrast to control group.
Situational Crime Prevention The science of reducing opportunities for crime. A set of 25 techniques divided among five categories: increase offenders’ efforts, increase offenders’ risks, reduce offenders’ rewards, reduce provocations to offend and reduce excuses for offending.
Treatment area An area receiving a response (see Response group).
Treatment group See Response group.
Treatment See Response or Intervention.
Buffer zone Area around a facility, hot spot or treatment area used to account for diffusion or displacement (see Diffusion/Displacement area).
Diffused temporal clustering A relatively even, or random, spread of crime throughout 24-hour cycles.
Diffusion contamination Occurs when diffusion of benefits influences the control group or area during an evaluation. Leads to undervaluing the treatment (see Displacement contamination).
Diffusion of benefits Reducing crime beyond the focus of the prevention scheme; a multiplier of effectiveness.
Diffusion of benefits, crime type Additional crime types blocked.
Diffusion of benefits, geographical Additional prevention over space.
Diffusion of benefits, tactical Additional methods thwarted.
Diffusion of benefits, target Additional targets protected.
Diffusion of benefits, temporal Additional prevention over time.
Diffusion/Displacement area Areas used to detect diffusion of benefits and displacement that are separate from control group and treatment group.
Displacement contamination Occurs when crime is displaced into the control group or area during an evaluation. Leads to inflation of effectiveness (see Diffusion contamination).
Displacement countermeasures Prevention implemented to prevent expected displacement.
Displacement Offenders changing their behaviour to thwart preventive actions.
Displacement, crime type Offenders change type of crime.
Displacement, geographical Offenders move spatially.
Displacement, tactical Offenders switch method for committing crime.
Displacement, target Offenders switch type of target or victim.
Displacement, temporal Offenders switch time or day.
Adaptation Long-term changes in offender population behaviours in response to crime prevention.
Anticipatory benefits Benefits from crime prevention that begin prior to initiation of crime prevention treatment.
Anticipatory benefits, pseudo The appearance of anticipatory benefits caused by smoothing data (i.e. the use of a moving average).
Benefit-cost The ratio of benefits to costs or benefits minus costs.
Benefits The value of crime prevented and of positive side effects of prevention.
Cost-effectiveness The ratio of response costs to crimes prevented. It is a measure of the cost of preventing a single average crime.
Costs Expenses or hardships associated with criminal events or prevention measures.
Costs, fixed Costs that cannot be changed for long periods.
Costs, response Costs of the intervention to prevent crime.
Costs, variable Costs that can be changed in a short time period.
Gross Effect Crime in the response area before the treatment, minus crime in the response area after the treatment. A positive result indicates a crime reduction (see also Net Effect, Weighted Displacement Quotient, and Total Net Effect).
Impact evaluation A research study to determine if the response changed the problem.
Net Effect The change in crime in the response area relative to change in crime in the control area (see also Gross Effect, Weighted Displacement Quotient, and Total Net Effect).
Process evaluation Assessing how a response was implemented.
p-value The probability that the difference between two sets of statistics is due to randomness (see Significance test).
Regression to the mean The tendency for abnormal high or low levels of crime to move back to their normal levels.
Significance level A threshold below which one rejects the possibility that the difference between two sets of statistics is due to randomness. Often 0.05 (or 5%) is the rejection threshold (see Significance test).
Significance test A statistical procedure used to determine whether the difference between two groups of numbers is due to randomness.
Time-window effect The underestimation of repeat victimisation due to using a set time period.
TNE See Total Net Effect.
Total Net Effect A formula for measuring the full impact of a response on a treatment area and diffusion/displacement area, while accounting for changes in a control area (see also Gross Effect, Net Effect and Weighted Displacement Quotient).
WDQ See Weighted Displacement Quotient.
Weighted Displacement Quotient A formula for measuring the effects of diffusion of benefits and displacement (see also Gross Effect, Net Effect and Total Net Effect).