1. psychlotron.org.uk Which is the most violent country? Murders/year United States (1999)15,434 Taiwan (1996)1785 Estonia (1994)423 Japan (1994)770 England & Wales (1997)725 Figures based on data obtained from http://www.guncite.com/gun_control_gcgvinco.html

2. psychlotron.org.uk Which is the most violent country? Annual Murders/100,000 pop. United States (1999)5.70 Taiwan (1996)8.12 Estonia (1994)28.21 Japan (1994)0.62 England & Wales (1997)1.41 Figures based on data obtained from http://www.guncite.com/gun_control_gcgvinco.html Crime numbers do not permit comparisons between places or over time. Crime rates (the number of crimes per unit of population per year) do.

3. psychlotron.org.uk Today’s session You are learning about...You are learning to... Measuring crime Assess the validity of measurements Identify factors that can distort measurements

4. psychlotron.org.uk Why would we want to know how much crime there is?

5. psychlotron.org.uk The Republic of Elbonia is a newly created nation. Like most nations, they have a government, a civil service, a judicial system and a police force. They want to be able to keep track of how much crime occurs in their country and have asked for your help. How would you measure crime in Elbonia?

6. psychlotron.org.uk Ways of measuring crime Official statistics – Crimes reported to the police – Court & prison statistics General population surveys – Victimisation surveys – Offender surveys

7. psychlotron.org.uk Police statistics Recorded as a crime Possibly criminal act Noticed by public Designated a crime by public Police attention Designated a crime by police In what ways might this process produce an inaccurate account of the crime rate?

8. psychlotron.org.uk Court & prison statistics In which ways might the true extent of crime be distorted by looking at: – The numbers of people convicted of various types of offence? – The numbers of people imprisoned for various types of offence?

9. psychlotron.org.uk General population surveys In which ways might the British Crime Survey be a more and a less valid measure of crime than police statistics? Why might a general population offender survey underestimate the extent of more serious crimes?

10. psychlotron.org.uk General issues Crime data, like most psychological data, are of ‘limited usefulness in limited circumstances’ (Howitt, 2009; p.21) – Each offers a different perspective on crime rates – Different measures have different uses – Measures can be triangulated – Problem is not the data but their interpretation

11. psychlotron.org.uk General issues There is a ‘dark figure’ of unreported and unrecorded crime – Which types of crime do you think are most likely to make up the ‘dark figure’? Generally, the more serious crimes are more likely to be noticed & reported, so much of the dark figure is less serious crimes