Analysis of responses to the 2013 Consultation regarding the redraw of Data Zones

Summary of findings

The majority of responses suggested some changes to provisional 2011 Data Zone and 2011 Intermediate Zone boundaries based on their local knowledge. Based on the provisional boundaries, we made changes to around 12% of Data Zones across Scotland; this figure varied from no changes in nine Local Authorities such as Dundee City and Clackmannanshire, to changes to 95% of Data Zones in Stirling. All changes were done through consultation with individual Local Authorities to ensure the boundaries reflected knowledge of communities and small areas. Further information about the changes at Local Authority level are provided in Annex 1 of this report.

In total 43 responses were received. Over 50 % of responses received were from Local Authorities. The rest were from public bodies, third sector and private companies.

Table 1.1 Summary of responses to individual questions

Consultation question 1. Are you content with the proposed 2011 Data Zones?

Since their inception, Data Zones have become the main small area geography used for presenting statistics. They are the core geography behind the Scottish Neighbourhood Statistics website (www.sns.gov.uk) and the Scottish Index of Multiple Deprivation in addition to being the main small area geography for a wide range of statistical outputs.

2011 Data Zones were built up from 2011 Census Output Areas (COAs) and met tight constraints on population thresholds (generally 500 - 1,000 household residents).

Many respondents were not content with the proposed 2011 Data Zones; however respondents were generally happy with the reasoning behind why 2001 Data Zones were being reviewed. The majority of suggested changes requested were based on local knowledge and were generally accepted.

Respondents suggested specific changes to local 2011 Data Zones for the following reasons:

• Alignment to Multi Member Wards, settlement boundaries, neighbourhood / community council boundaries, civil parishes, natural communities, natural neighbours, communities of interest and other administrative boundaries.
• After consulting with Community Planning Partnerships to gain understanding of local areas.
• Planned demolitions of housing meant that the population of a proposed 2011 Data Zone would be below the population threshold in the future.
• Planned main roads dissecting Data Zones and splitting communities.
• New housing developments being built meant that the population of proposed 2011 Data Zones would be above the population threshold in the future.
• Knowledge of island communities and links to mainland / other islands.

Consultation question 2. Do you agree that 2011 Data Zones should use the median methodology for the calculation of centroids?

The Data Zone centroid represents the centre of the area. This is not the geometric middle of the Data Zone, but a point that represents the population centre. The main use of the centroid is to determine which higher level geography the Data Zone would be allocated to.

For 2001 Data Zones, centroids were calculated as the population weighted centre (essentially the mean centre) of all 2001 Census Output Areas contained within the Data Zone. The methodology used can be found here:
http://www.scotland.gov.uk/Resource/Doc/933/0082884.doc

The median is a measure of central tendency and, broadly speaking, the median can be thought of as the 'middle' value. The median is calculated by putting the observations in order, from lowest to highest, and then taking the value in the middle, (or calculating the mean of the two middle values if there are an even number of observations). This is different from calculating the mean, which is done by summing all the values together and dividing by the number of observations.

The majority of respondents agreed that median centroids should be used rather than mean centroids.

Comments received for this question include:

• Median is less likely to be influenced by values far away from what would be considered to be the population centre of the Data Zone
• Median provides a better means of determining how urban or rural a particular area is
• Impact of change small overall
• In principle methodology change makes sense
• Median rather than mean ensures that measures are less skewed by outliers in data arising as result of relatively small numbers of individuals
• Makes comparison between 2001 Data Zones and 2011 Data Zones harder

Therefore this methodological change has been accepted.

Consultations question 3. Are you content with the proposed best 2011 Intermediate Zones?

Intermediate Zones (sometimes called Intermediate Geographies) are similar to Data Zones and share many of the same traits and problems. The key difference is their size: Intermediate Zones have a population of around 4,000 and are built up from Data Zones.

The majority of respondents were content with the updated boundaries and recognised that 2011 Intermediate Zones were created and any changes to 2011 Data Zone boundaries will be reflected in 2011 Intermediate Zones. A few responses detailed changes to one / many 2011 Intermediate Zones which are reflective of their suggested changes to 2011 Data Zones above.

Respondents suggested specific changes to 2011 Intermediate Zones for the following reasons:

• Substantial growth in population
• Better reflection of communities
• Alignment with operational areas e.g.: NHS and Social Work
• Better reflection of local ideas of neighbourhood
• Better reflection of natural community boundaries

2011 Intermediate Zones boundary files will be published alongside 2011 Data Zones.