Research Methodology

Data and sample sizes

There are three different versions of data sets produced through this research – which have varied due to the sample sizes available for each location. 

The locations within this research vary from areas with a population of 44,449 in Braintree and Bocking down to a population of 227 in Pentlow, which clearly provide very different sample sizes of data.   

Example of how sample sizes have affected the data collected  

Average waiting times have only been reliably produced for the larger locations – The District as a whole and the three towns. The larger villages (like Coggeshall and Earls Colne) have less than 20 homes which become available to rent per year (lets) and this does not provide enough of a sample size to produce a reliable average. 

In order to determine average waiting times for a location there needs to be a reasonably high number of people who were allocated homes in that location. 

There would need to be samples of lets for the different priority bands ‘A to C’ (3 variables) across different property types e.g. 1 bedroom flat, 2 bedroom bungalow etc (8 variables). This means that 24 (3x8) lets would need to have occurred just to provide 1 sample of a waiting time for each property type.  To obtain an average of these waiting times we would need a few examples of lets (say 4 upwards at the very least). This shows we would need 100+ lets over the three years of data to start to record average waiting times. 

The three versions of the Data 

There are three different versions of the data collected due to the different sample sizes available. 

  1. District & Towns - The Braintree District, Braintree & Bocking, Halstead and Witham 
  2. Larger Villages - These include the six largest Key Service Villages of Coggeshall, Earls Colne, Hatfield Peverel, Kelvedon, Sible Hedingham and Silver End and the other seven larger villages in the District (over 1,500 population size) of Black Notley, Cressing, Feering, Great Notley, Great Yeldham, Rayne and Steeple Bumpstead. 
  3. Parishes - For all other parish locations. 

The District and towns have much wider data and analysis due to the larger sample size, which includes waiting times and movement rates. As the data sample sizes get smaller for the villages, the key housing needs statistics focus more on analysis of the Census data and include more historic data from Braintree District Council's records.