Assessing elements of crime based on an agent simulation of a street

robbery

Jakub Nowakowski, Czeslaw Jedrzejek, Jakub Dutkiewicz

Poznan University of Technology, Poland

RuleML Challenge 2015, August 5, 2015

Starting point: ontology of guilt

For Poland

Architecture: agent system + expert system

Expert system

The Expert system decides if a crime took place by determining if:

1. a situation can be considered an action,

2. the action is forbidden by law,

3. the action forbidden by law that is illegal (no justification),

4. the action is socially harmful,

5. the action is blameworthy (no excuse).

1. Can a situation be considered an action?

2. Is the action forbidden by law?

3. Is the forbidden action illegal?

4. Is the action socially harmful?

5. Is the action blameworthy?

Agent system

The agent system is divided into four modules:

1. controller,

2. environment,

3. thief and victim.

1. The environment

The street is a 3x10 field, where agents can move.

The street is open on the shorter ends for the agents to run away.

All states of things that are perceived by agents are recorded in the environment module.

2. The controller

The controller module:

• initializes the simulation,

• supervises rounds of the simulation,

• activates auxiliary functions,

• cleans the initial values at the end of the simulation.

3. The thief and the victim

The agent module:

• perceives changes in the environment,

• calculates the utility factor to choose from possible scenarios,

• chooses an action plan according to will,

• Performs a chosen action.

Simulation nr 1 Here are the values for the characteristics of both agents.

The victim is going to be less tough on the thief.

Map of the street with agents.

[agent’s utility index] = [agent’s confidence] – [opponent estimated utility index]

[agent’s confidence] = [vigour] + [bravery] + [suspiciousness] + [weapon]

[opponent estimated utility index] = [opponent vigour] + [opponent suspiciousness] + [estimated opponent weapon]

[estimated opponent weapon] = 0 if [opponent suspiciousness] < 5; = 2 if 4 < [opponent suspiciousness] < 7; = 5 if 6 < [opponent suspiciousness] < 9;

Output of the expert system.

Agents move according to their plan and will.

Next turn.

Next turn.

Next turn.

Next turn.

Next turn.

Thief’s action utility index is between (0 – 3) so it does not go to the next step which is posing a threat.

End of the simulation: there is no robbery.

Simulation nr 2

This scenario is interesting because both agents have low visible indices (vigour, suspiciousness), but high invisible index (bravery), and the thief has a knife. They will underestimate eachother.

The victim will try to bypass the thief.

Next turn.

Victim went down.

Next turn.

Next turn.

Next turn.

Next turn.

Next turn.

Next turn.

One of the threats listed in the Model Penal Code.

Posing threats is an illegal and socially harmful action but in the definition of robbery there must be a seizure of property.

Next turn.

Next turn.

End of the simulation: thief takes the property - there is a crime of robbery.

Thank you for your attention.