This exercise is undertaken at local authority level, using figures for high technology and total employment derived from the annual employment surveys for 1991 and 1997. Section 3.4 provides detail on the SIC and the definition of high technology used in this study.
High technology figures are manipulated to identify rates of change in the high technology sector between 1991 and 1997 in each local authority area. High technology figures are also used to estimate the strength of representation (compared to the national average) o f the high technology sectors. This is done by calculating the location quotient for each local authority in ROSE. The method used to calculate rates o f change and location quotient are detailed below.
Finally, the resulting geographies are represented on a GIS map. The GIS system and methods used, and the limitations of it, are outlined below.
3.9.1 Location Quotient
same share of total employment in the district as it does in Great Britain. If the LQ is more than one, the activity is over-represented in the district; it accounts for a greater share of jobs than it does nationally. In other words, there is a cluster of that particular sector. Conversely, an LQ smaller than one indicates that the activity is under-represented in the chosen district. Importantly, the location quotient does not indicate whether or not the representation of the sector is higher or lower than it has been in recent years; nevertheless is provides a simple method of assessing the importance of a particular sector to the local economy at a fixed point in time.
This methodology is commonly used in sectoral analysis. Examples include W estern Sunrise, where Hall et al 1987 et al (1993) identified a geography of high technology along the M4 corridor using location quotients. Sennett and Simmie (1999) used LQs to identify high technology clustering throughout the wider South East region, including London. Two other examples are research studies undertaken for the London Planning Advisory Committee on Industrial Demand in London (1999), and Business Parks in London: Demand and Capacity (1999). These both used the LQ methodology to identify representation of particular sectors in the London economy, in the former study this extended to a range of sectors, the latter sector focused on particular aspects of the office sector.
To calculate the LQ for high technology industry in each authority in the South East, the following 4 processes were followed and repeated for each district.
• Raw data was collected. For this calculation, high technology employment statistics (according with the OECD definition) were collected for the district concerned, and also Great Britain as a whole. Total employment figures for the district and Great Britain were also collected. For the purposes of this study, these were taken from the Annual Employment Survey 1997, and downloaded using the NOMIS.
• National high technology representation was calculated. This is done by dividing total high technology employment for Great Britain by total employment figures for Great Britain, in order to calculate high technology employment as a proportion o f total employment.
• Local high technology representation was calculated. This is done by dividing total high technology employment for the district by total employment figures for the district, in order to calculate high technology employment as a proportion of total employment.
• Calculation of LQ. To calculate the LQ, the local high technology representation is divided by the national high technology representation. The resulting figure is the LQ.
This process was reproduced for the 99 districts in the South East. All calculations are reproduced in Appendix 4.1. The results are produced and analysed in Chapter 4, Section 4.4.
3.9.2 Rates o f High Technology Employment: The Local Differential
Literature on the South East economy, and on knowledge-driven industries in general, indicate a high representation of high technology industry in the South East, and imply that the sectors are growing (SEEDA, 1999, EEDA 1999, Simmie and Sennett, 1999, Hall et al, 1987, Sainsbury,
1999).
In order to identify not only the current representation of high technology industries in South East, but to also ascertain whether that representation is part o f a growing or a slowing trend, an analysis of rates of change in high technology employment is undertaken for each district. This is achieved by calculating the number of jobs that have been lost or gained in the sector between two periods.
Calculating gross change in total high technology jobs in one district over two points in time is a crude form of analysis. This is because it does not isolate the cause of growth, and the extent to which it is attributed to national structural change in the same sector. For example, if the high technology sector were identified to grow by ten percent between 1991 and 1997 in Havant, creating 1,000 jobs, it would not be possible to conclude that this was because Havant was particularly attractive to high technology industries. A contrary, but equally valid explanation could be that national growth in the high technology sector converted into more high tech jobs in Havant. In other words, Havant would only have a growing and healthy high technology sector if it were proved to generate jobs above and beyond those that would have been created by structural changes in the national economy.
This analysis seeks to isolate the extent to which local economic factors explain the growth or decline in the high technology sector in the South East. This figure is known as the differential.
while small firms fuel the cluster, firms of different sizes also require enough space in close proximity to other firms.
• If and how the planning system ensures that companies can locate in ‘good working environments’. Here, there is emphasis on the quality of the provision and whether it meets the requirements of a high technology, or knowledge-driven firm. It is not sufficient to provide enough space, but to provide the right kind of space. It is at this juncture, in assessing what is the ‘right kind of space’ that considerations relating to infrastructure and the proximity of other facilities (the remaining two identified land use components of clusters) come into play.
These three aspects of the planning system are the basis for the survey design for this stage of the research. They provide an answer to the first research question, and in so doing provide insights into whether or not the planning system needs reforming (research question 2).
The conversion of these three questions into a survey format is discussed in section 3.14.