The Guardian recently contacted me with a new extract of data related to the riots and was interested in some further analysis looking at the IMD. The data comprised records for 835 people who have appeared in court on charges related to the 2011 riots. The data have been collected from magistrate courts and represent roughly a 42% sample. This is calculated by comparing the Guardian data file record frequency with the ministry of justice counts of people appearing before the courts by midday on 12th October 2011 (1,984 people). Within the Guardian data there were 83 cases with duplicate postcodes; which the Guardian identified as either the same person appearing in court multiple times, or, that these related to multiple people from the same postcode. Duplicates were included for these analyses; however, depending on the distribution between the two groups, this could introduce bias into these findings.
Each record comprised a postcode and enabled identification of the Lower Super Output Area (LSOA) in which the address resided. Of the 835 records there were 767 matches; leaving 68 records without LSOA codes. Typically these records either contained an erroneous postcode, or, a postcode recorded at either Sector or District level. Using this information it was then possible to match the Index of Multiple Deprivation for both 2004 and 2010.
These latest data showed that around 59% of those appearing in court identified their residential location as being within the 20% most deprived areas in England (overall 2010 IMD). Over the different domains of the IMD, these patterns were reproduced with little variation from the overall pattern (See Figure 1), perhaps with the exception of the Education domain which was a little more evenly distributed, albeit still bias towards more deprived areas.
According to the change in IMD decile between 2004 and 2010; for 59% of those addresses appearing in the sample, these areas had not changed decile; however 15% had got worse and 26% better. Ordering into decile bins reduced some detail in these trends; however, if the raw position of change in rank was considered, 37% were worse and 64% better.
These patterns are better explained by Table 1 which shows a cross tabulation between the IMD decile position in 2010 and the movement in position since 2004 for those appearing in the sample data. What this is showing is that for a large proportion of the sample, their addresses are within areas which are very deprived, and have either stayed very deprived since 2004 or become more deprived.
Table 1: Decile Change Cross Tabulated with 2010 IMD Decile