CAMSIS: Bibliographic Review

See also: Work in Progress


The ideas behind CAMSIS scales (developed from the original 'Cambridge Scale') cover not just a particular measure, but a whole distinctive theoretical approach to social stratification. This short statement is intended to provide a guide towards relevant reading, rather than to give a full account of the approach. A more extended introduction can be found in Prandy 1999b.


Theoretical background

An early paper that deals with the problems inherent in attempts to measure stratification arrangements using the judgements of individuals is Stewart & Blackburn 1975. There is a very brief account of the Cambridge Scale and its construction in Stewart et al 1973, but the basic presentation is in Stewart et al 1980, particularly in Part I, which deals specifically with the Cambridge Scale. However, the whole book is essential reading for those who wish to understand the general approach. A short extract from one of these other, important sections is included in Holmwood 1996. Some of the broad theoretical ideas are developed in Holmwood & Stewart 1983, Prandy & Bottero 1995, Blackburn & Prandy 1997, Bottero and Prandy 2003, and Bottero 2005b. There is an extension of the underlying ideas to include gender in Bottero 1998. Holmwood & Stewart 1991 incorporate these ideas within a wider context of the nature of explanation in social science, particularly its relation to social theory. Bottero 2005a incorporates the approach in the wider context of understanding social stratification generally. Bottero et al. 2009 draw links between these approaches and ideas from a Bourdieusian perspective on social stratification.




CAMSIS scales are sometimes given the generic title 'Social Interaction Distance' scales, as they can be calculated from any data on social linkages between occupations. In different contexts, data on occupations linked by friendship, marriage, parent-child combinations, and within-career intra-generational mobility, has been used to derive SID scales. Prandy and Lambert 2003 argue that all such measures of social interaction are likely to generate the same empirical patterns of a stratification structure of Social Interaction Distance. This is used to justify why contemporary CAMSIS scales are usually calculated on the basis of pairs of occupations linked by marriage or cohabitation (since this data is easiest to obtain from various empirical sources).

The original version of the Cambridge Scale , which was created from a data set using only male white-collar workers, was based on Multi-dimensional scaling techniques (MDS, for background see the NewMDSX website), using patterns of the occupations of friends (see the reference to Stewart et al 1980, above). It was subsequently revised, particularly in order to accommodate female incumbents of occupations (Prandy 1986). The revision is more fully described in Prandy 1990 (reprinted in Holmwood 1996), where there is also a brief outline of the evidence for the Cambridge Scale's value in empirical analyses. This revision utilised, unwittingly, a variant form of Correspondence Analysis (CA) and in a more conventional form this was the method used in the Family History Project (Bottero and Prandy 2001), using data on marriage and . Correspondence analysis is also used in the current development of CAMSIS international measures, though our preferences has shifted to using Goodman's class of "RCII" association models (RC) for the scale construction process (also known as log-multiplicative models) (Prandy and Lambert 2003).

A discussion of each of these approaches in slightly greater detail can be found at this section of the 'construction' webpages at this site. Extensive details on the practical estimation of CAMSIS scales using both CA and RC models are also provided in the construction sections of these webpages.

There are certain methodological principles to the derivation of SID scales which are associated with the CAMSIS project but are not necessarily required of a SID approach. The first concerns the difference between universaility and specificity in occupation-based social classifications (see Lambert et al. 2008; Lambert et al. 2006): SID scales derived in the CAMSIS project have been deliberately specific in terms of countries, time periods, and men and women (that is, different scales exist for different countries, time periods and for men and women). A second issue concerns the level of detail of occupational measurement: SID scales dervied in the CAMSIS project have used as much detail on different occupational positions as available (e.g. Lambert et al. 2006). Neither of these principles are a pre-requisite for using the CAMSIS approach, however. In an important recent development, de Luca, Meraviglia and Ganzeboom (2010) have used the methodologies of the CAMSIS approach to develop a universal (cross-national) scale applied to a relatively small number of occupational units (a measure known as 'International CAMSIS' or I-CAM - see also described the 'versions' section of this site).

Several other research projects also estimate SID scales in similar ways to those of the CAMSIS project. An early example was implemented by Laumann and Guttman (1966). Of most contemporary impact, a series of derivations using friendship and marriage patterns are associated with Chan and Goldthorpe (2004, 2007; Chan 2010). Indeed one scale linked to this approach has been published in an edited book where it is directly linked to dicussion of CAMSIS scales (Bessudnov 2012). However, the scale derivations associated with Chan and Goldthorpe have normally been distinguished from CAMSIS on the grounds that they are interpreted as measures of 'social status' rather than of 'social stratification', and in methodological terms have usually used a smaller range of different occupational unit groups and have not differentiated male and female scales.



Since the 1960's, we have seen social scientists generating Social Interaction Distance scales using a number of alternative software packages. Examples that we are aware of include:

Software used in implementations affiliated to the CAMSIS approach

  • In the original 'Cambridge scale' derivations (Stewart et al. 1980; Prandy 1990), a multi-dimensional scaling programme called MINISSA was used (with adaptations to accomodate the matrix size invoolved - see Stewart et al., 1980: 37)
  • For the wider CAMSIS project (2000-present), Ken Prandy, Paul Lambert and colleagues wrote programmes, and provided usage instructions, exploiting a combination of the SPSS and lEM (Vermunt, 1997) packages using their respective correspondence analysis and RC-II association model routines.
  • As documented at the 'make_camsis' Stata support page, Paul Lambert also uses Stata for, either, the entire scale derivation process (using only correspondence analysis), or, for the data manipulation stages of the process as precursors to an analysis in lEM
  • Stephen McTaggart, working with data for New Zealand, has written SAS programmes to undertake correspondence analysis routines replicating the SPSS and lEM approaches documented on the CAMSIS website.

Other software used in published scales of social interaction distance 

  • The versions described by Chan and Goldthorpe (2004),Chan (2010) and Bessudnov (2012) use the gnm package in R to develop scales based upon RC-II association models
  • Laumann and Guttman (1966) used smallest space analysis algorithms developed by Guttman (1968) and Lingoes (e.g. 1966) to develop a scale for the US based upon pattern analysis of friendship patterns
  • MacDonald (1972) used MDSCAL to develop scales for the UK based upon multi-dimensional scaling of intergenerational mobility patterns
  • Rytina (1992) programmed in GAUSS to develop scales for the US based upon RC-II association models for intergenerational mobility patterns
  • Many other analyses of social mobility have included an analysis of social distance between occupational classes calculated through the log-linear modelling tools applied to the relevant context. Examples include:
    • Blau and Duncan's (1967) use of the same software as Laumann and Guttman (1966) to analyse the structure of intergenerational mobility patterns in the US (see Stewart et al. 1980: 34)
    • Separate contributions by Hope, Duncan-Jones, and Macdonald, within Hope (1972) all involved scaling represenations of intergenerational mobility distances in the UK and US.
    • Breen (1985) wrote GLIM macros to calculate distances between occupational categories for social mobility analysis
    • A series of analysis of the Netherlands and other countries presented in Luijkx (1994) demonstrate the use of lEM and LCAG for calculating intergnerational mobility distances.


Selected empirical applications using CAMSIS scales

The original version of the Cambridge Scale was used in Prandy et al 1982 and Prandy et al 1983, but it is the first revised version that has so far been widely used for a wide range of applications. These include the analysis of social mobility (Prandy 1998a, Lambert et al 2007; see also the closely related work of Rytina 1992, 2000), education (Blackburn & Marsh 1991; Marsh & Blackburn 1992; Blackburn & Jarman 1993), illness and mortality (Chandola 1998, 2000; Bartley et al 1999a, 1999b; Prandy 1999; Sacker et al 2000, 2001)  and political party identification (Prandy 2000b). In each of these cases the Cambridge Scale is compared, empirically and theoretically, with conventional 'social class' approaches. The scale has also been successfully used in the analysis of occupational aspirations (Furlong & Biggart 1999), ethnic inequality (Blackburn et al 1997; Model 1999) and occupational segregation by gender (Blackburn et al 1999, 2001). More generally, a recent edited book, Lambert et al. (2012), which is linked to the 'Social Stratification Research Seminar' series, features a number of different papers use CAMSIS scales as outcome or explanatory measures.




There is a brief account of seminar papers considering the 'class' and 'stratification' approaches in S.C.P.R., 1988, and Jacoby 1986. There are also debates between their proponents in Prandy & Blackburn 1997 and Evans 1998, and in Blackburn 1998, Prandy 1998b and Rose 1998. Vågerö 2000 has a comment on the Sacker et al article. Prandy 2002 offers a further critique of the conceptualisation of stratification in terms of class.

Chan and Goldthorpe's (2007) paper has been particularly influential in advocating the position that social interaction distance scales measure a pattern of 'social status' which is empirically and theoretically separable from the structure of class, and many recent studies have followed this position (e.g. Bukodi et al. 2011; Torssander and Erikson 2010). Counter-arguments have been made by de Luca et al (2010b) and, in work which is still ongoing, by Lambert and Bihagen (2007; Bihagen and Lambert 2012), who argue that SID and class measures do not detect empirically distinct dimensions, but primarily measure the same thing, which is best labelled 'social stratification'.



International aspects

An ESRC award 2000-2003 provided funding for a major revision and updating of social interaction based scales for the UK, and the production of a set of comparable scales for a number of other countries. These scales now come under the generic title of CAMSIS (latest details of available CAMSIS scales). A major difference between the Cambridge Scale and the recent CAMSIS versions is that the latter have been constructed solely on the basis of marriage patterns (whereas the former utilised friendship and marriage patterns). A similar social distance scale, using marriage patterns, has been developed for the Netherlands (Bakker 1993), where it has been shown to be significantly superior to an occupational prestige scale in predicting aspects of lifestyle and political behaviour. One advantage of marriage data is that they can be derived from censuses or very large-scale official surveys. Another is that they are to a substantial degree directly comparable across countries. This combination of being nationally (and even time-period) specific yet directly comparable is a major advatage of CAMSIS scales. Prandy and Lambert 2003 discuss the development of the revised CAMSIS scale for the UK, showing that it is very closely comparable to the revised version of the Cambridge Scale. Discussions of the international comparative aspects of the CAMSIS project are to be found in Prandy and Jones 2001.

Some articles give general descriptions of CAMSIS versions for specific countries: Australia, CAMSIS-OZ (Jones and McMillan 2001); Switzerland, CAMSIS-CH (Bergman and Joye 2001; Bergman et al 2002).



Historical versions

As part of the Family History Project (1998-2002) , we developed two historical versions of the scale for Britain, one for the period 1777-1866, the other for the period 1867-1913. The background to this historical work is given in Prandy 1993 and an account of the construction of historical versions of the scale is in Prandy & Bottero 1998, Bottero & Prandy 1999 and Bottero & Prandy 2001. These are used for the analysis of work-life trajectories and social mobility in Prandy & Bottero 2000a and Prandy & Bottero 2000b.

As part of the HIS-CAM project (2004-present) we have developed historical versions for Britain, Germany, France, Sweden, the Netherlands, Belgium, Canada, and the USA, using the HISCO occupatonal unit group classification. Publications on this work are available from the HIS-CAM website.




Practical details

'Index files' allowing the linkage of CAMSIS derived scales to occupational base units are distributed through these webpages, see the 'downloads' and 'versions' pages. The latter page has more extended details, whilst the former provides a quick link to the most relevant data files. Further guides on using CAMSIS scales can be found in this page, and, in many examples, in 'readme' files or version report documents that accompany the index files.

A by-product of generating CAMSIS scales is often additional metadata linking occupational unit groups with other information (such as descriptive value labels or other occupation-based social classifications). Some relevant resources are available on our 'occupational classifications' page, and an attempt to prepare these in a more comprehensive way is made by the GEODE project webpages.





B.F.M. Bakker (1993) A new measure of social status for men and women: the social distance scale, Netherlands Journal of Social Sciences 29: 113-129 (back)

M. Bartley, A. Sacker, D. Firth and R. Fitzpatrick (1999a) Social position, social roles and women's health in England: changing relationships 1984-1993, Social Science & Medicine 48: 99-115 (back)

M. Bartley, A. Sacker, D. Firth and R. Fitzpatrick (1999b) Understanding social variation in cardiovascular risk factors in women and men: the advantage of theoretically based measures, Social Science & Medicine, 49: 831-845 (back)

Blau, P. M., & Duncan, O. D. (1967). The American Occupational Structure. New York: Wiley. (back)

M. M. Bergman and D. Joye (2001) Comparing Social Stratification Schemas: CAMSIS, CSP-CH, Goldthorpe, ISCO-88, Treiman, and Wright. Cambridge Studies in Social Research (back)

M. M. Bergman, P. S. Lambert, K. Prandy and D. Joye (2002) Theorisation, construction and validation of a social stratification scale: Cambridge Social Interaction and Stratification Scale (CAMSIS) for Switzerland, Swiss Journal of Sociology, 28: 441-460 (back)

Bessundov, A . (2012). A relational occupational scale for Russia, in P. S. Lambert, R. Connelly, R.M. Blackburn and V. Gayle (eds) Social Stratification: Trends and Processes (pp53-65). Aldershot: Ashgate (back).

E. Bihagen & P.S. Lambert (2012) Class and status: One or two forms of stratification? Paper presented to the Equalsoc conference, Stockholm, 24 September 2012 (back)

R.M.Blackburn (1998) A new system of classes: but what are they and do we need them?, Work, Employment and Society 12: 735-741 (back)

R.M. Blackburn, B. Brooks and J. Jarman, (1999) Gender Inequality in the Labour Market: the vertical dimension of occupational segregation, Cambridge Studies in Social Research (back)

R.M. Blackburn, B. Brooks and J. Jarman (2001) The vertical dimension of occupational segregation, Work, Employment and Society 15: 511-538 (back)

R.M. Blackburn, A. Dale and J. Jarman (1997) Ethnic differences in attainment in education, occupation and life-style, in V. Karn (ed), Ethnicity in the 1991 Census: Volume Four (ONS/Stationery Office) (back)

R.M. Blackburn and J. Jarman (1993) Changing inequalities in access to British universities, Oxford Review of Education 19: 197-215 (back)

R.M. Blackburn and C. Marsh (1991) Education and social class: revisiting the 1944 Education Act, British Journal of Sociology 42: 507-536 (back)

R.M. Blackburn and K. Prandy (1997) The reproduction of social inequality, Sociology 31: 491-509 (back)

W. Bottero (1998) Clinging to the wreckage? Gender and the legacy of class, Sociology 32: 469-490 (back)

W. Bottero (2005a) Stratification: Social Division and Inequality (Routledge) (back)

W. Bottero (2005b) Interaction distance and the social meaning of occupations, Sociological Review 53(2): 56-72 (back)

W. Bottero, P.S. Lambert, K. Prandy, S. McTaggart (2009). Occupational Structures: The Stratification Space of Social Interaction. In K. Robson & C. Sanders (Eds.), Quantifying Theory: Pierre Bourdieu (pp. 141-150). Amsterdam: Springer Netherlands. (back)

W. Bottero and K. Prandy (1999) Women's Occupations, Mobility and the Social Order, Cambridge Studies in Social Research (back)

W. Bottero and K. Prandy (2001) Women's occupations and the social order in nineteenth century Britain, Sociological Research Online, 6 (2), 2001 (back)

W. Bottero and K. Prandy (2003) Social interaction distance and stratification, British Journal of Sociology, 54: 177-198 (back)

Breen, R. (1985). Log-multiplicative models for contingency tables using GLIM. GLIM Newsletter, 10, 14-19. (back)

E. Bukodi, S. Dex & J.H. Goldthorpe (2011) The conceptualisation and measurement of occupational hierarchies: a review, a proposal and some illustrative analyses. Quality and Quantity, 45: 623-629(back)

Chan, T. W., & Goldthorpe, J. H. (2004). Is There a Status Order in Contemporary British Society. European Sociological Review, 20(5), 383-401.(back)

Chan, T. W., & Goldthorpe, J. H. (2007). Class and Status: The Conceptual Distinction and its Empirical Relevance. American Sociological Review, 72, 512-532. (back)

Chan, T. W. (2010). The social status scale: Its construction and properties, in T. W. Chan (ed) Social Status and Cultural Consumption (pp28-56). Cambridge: Cambridge University Press (back).

T. Chandola (1998) Social inequality in coronary heart disease: a comparison of occupational classifications, Social Science & Medicine 47: 525-533 (back)

T. Chandola (2000) Social class differences in mortality using the new UK National Statistics Socio-Economic Classification, Social Science & Medicine 50: 641-649 (back)

De Luca, D., Meraviglia, C. & Ganzeboom, H.B.G. (2010a). ICAM: The International CAMSIS scale. First presented at ISA RC28, Hafia, April 14 2010, software available at

D. de Luca, C. Meraviglia, C. & H..B.G. Ganzeboom (2010b) Social distance and socio-economic status: Different dimensions or different indicators of occupational stratification. Paper presented to the Social Stratification Research Seminar, Utrecht, 10 September 2012 (back)

G. Evans (1998) On tests of validity and social class: why Prandy and Blackburn are wrong, Sociology 32: 189-202 (back)

A. Furlong and A. Biggart (1999) Framing 'choices': a longitudinal study of occupational aspirations among 13- to 16-year-olds, Journal of Education and Work, 12: 21-35 (back)

Guttman, L. (1968). A general nonmetric technique for finding the smallest coordinate space for a configuration of points. Pyychometrika, 33: 469-506. (back)

A. Jacoby (ed) (1986) The Measurement of Social Class, Proceedings from the Social Research Association seminar on "Measuring Employment Status and Social Class", London: Social Research Association (back)

K. Halstead, P. Elias and K. Prandy (1993) CASOC: Computer-assisted Standard Occupational Coding HMSO (back)

J. Holmwood (ed) (1996) Social Stratification Vol II (Edward Elgar) (back)

J.M. Holmwood and A.Stewart (1983) The role of contradictions in modern theories of social stratification, Sociology 17: 234-254 (back)

J. Holmwood and A. Stewart (1991) Explanation and Social Theory (Macmillan) (back)

Hope, K. (Ed.). (1972). The Analysis of Social Mobility: Methods and Approaches. Oxford: Oxford University Press. (back)

F. L. Jones and J. McMillan (2001). Scoring occupational categories for social research: a review of current practice, with Australian examples,Work, Employment and Society 15: 539-63 (back)

P.S. Lambert and E. Bihagen (2007) Concepts and measures: Empirical evidence on the interpretation of ESEC and other occupation-based social classifications. Paper presented to ISA RC28, Montreal, 14-17 August 2007. (back)

P.S. Lambert, R. Connelly, R.M. Blackburn and V. Gayle (2012) Social Stratification: Trends and Processes. Aldershot: Ashgate (back)

P.S. Lambert, K.L.L. Tan, V. Gayle, K. Prandy and M.M. Bergman (2008) The importance of specificity in occupation-based social classifications, International Journal of Sociology and Social Policy, 7/8. (back)

P.S. Lambert, K. Prandy and W. Bottero (2007) By slow degrees: Two centuries of social mobility and reproduction in Britain, Sociological Research Online, 12(1). (back).

P.S. Lambert, Zijdeman, R., Maas, I., Prandy, K., and van Leeuwen, M (2006) "Testing the universality of historical occupational stratification structures across time and space." Paper presented to the ISA RC 28 Social Stratification and Mobility spring meeting, Nijmegen, 11-14th May 2006. (back)

Laumann, E. O., & Guttman, L. (1966). The relative associational contiguity of occupations in an urban setting. American Sociological Review, 31, 169-178.(back)

Lingoes, J.C. (1966). An IBM-7090 Program for Guttman-Lingoes Smallest Space Analysis - III. Behavioral Science, 11: 75-6. (back)

Luijkx, R. (1994). Comparative loglinear analyses of social mobility and heterogamy. Tilburg: Tilburg University Press. (back)

Macdonald, J. (1972). MDSCAL and distances between socio-economic groups. In K. Hope (Ed.), The Analysis of Social Mobility: Methods and Approaches (pp. 211-234). Oxford: Clarendon Press. (back)

C. Marsh and R.M. Blackburn (1992) Class differences in access to higher education, in R. Burrows and C. Marsh (eds), Consumption and Class, Divisions and Change (Macmillan) (back)

S. Model (1999) Ethnic inequality in England: an analysis based on the 1991 Census, Ethnic and Racial Studies 22: 966-990 (back)

K. Prandy, A. Stewart and R.M. Blackburn (1982) White-Collar Work (Macmillan) (back)

K. Prandy, A. Stewart and R.M. Blackburn (1983) White-Collar Unionism (Macmillan) (back)

K. Prandy (1986) Similarities of life-style and the occupations of women, in R. Crompton & M. Mann (eds), Gender and Stratification (Polity) (back)

K. Prandy (1990) The revised Cambridge scale of occupations, Sociology 24: 629-655 (back)

K. Prandy (1992) Cambridge Scale Scores for CASOC Groupings (Sociological Reseach Group Working Paper, University of Cambridge) (back)

K. Prandy (1993) Marriage and Social Stratification in Nineteenth-century Britain (SRG Working Paper) (back)

K. Prandy and W. Bottero (1995) The Social Analysis of Stratification and Mobility (SRG Working Paper) (back)

K. Prandy (1997) Cambridge Scale Scores for Census Classifications 1961-1991 (Sociological Research Group Working Paper, University of Cambridge) (back)

K. Prandy (1998a) Class and continuity in social reproduction: an empirical investigation, Sociological Review 46: 154-178 (back)

K.Prandy (1998b) Deconstructing classes: critical comments on the revised social classification, Work, Employment and Society 12: 743-753 (back)

K. Prandy (1999a) Class, stratification and inequalities in health: a comparison of the Registrar-General's Social Classes and the Cambridge Scale, Sociology of Health and Illness 21: 466-484 (back)

K. Prandy (1999b) The social interaction approach to the measurement and analysis of social stratification, International Journal of Sociology and Social Policy 19: 215-249 (back)

K. Prandy (2000b) Class, the stratification order and party identification, British Journal of Political Science 30: 237-258 (back)

K. Prandy and W. Bottero (2000a) Reproduction within and between generations: the example of nineteenth-century Britain, Historical Methods 33: 1-15 (back)

K. Prandy and W. Bottero (2000b) Social reproduction and mobility in Britain and Ireland in the nineteenth and early twentieth centuries, Sociology 34: 265-281 (back)

K. Prandy and W. Bottero (1998) The use of marriage data to measure the social order in nineteenth-century Britain, Sociological Research Online 3,1 (back)

K. Prandy and R.M. Blackburn (1997) Putting men and women into classes: but is that where they belong? A comment on Evans, Sociology 31: 143-152 (back)

K. Prandy (2002) Ideal types, stereotypes and classes, British Journal of Sociology 53: 583-602 (back)

K. Prandy and F. L. Jones (2001) An international comparative analysis of marriage patterns and social stratification, International Journal of Sociology and Social Policy 21: 165-183

K. Prandy and P. S. Lambert (2003) Marriage, social distance and the social space: an alternative derivation and validation of the Cambridge Scale, Sociology 37: 397-411 (back)

D. Rose (1998) Once more unto the breach: in defence of class analysis yet again, Work, Employment and Society 12: 755-767 (back)

S. Rytina (1992) Scaling the intergenerational continuity of occupations: is occupational inheritance ascriptive after all? American Journal of Sociology 97: 1658-1688 (back)

S. Rytina (2000) Is occupational mobility declining in the United States? Social Forces 78: 1227-1276 (back)

A. Sacker, D. Firth, R. Fitzpatrick, K. Lynch and M. Bartley (2000) Comparing health inequality in men and women: prospective study of mortality 1986- 96, British Medical Journal 320: 1303-1307 (back)

A. Sacker, M. Bartley, D. Firth and R. Fitzpatrick (2001) Dimensions of social inequality in the health of women in England: occupational, material and behavioural pathways, Social Science & Medicine 52: 763-789 (back)

S.C.P.R. (1988) A fresh look at social classification: report of the March 1988 ESRC survey methods seminar, Survey Methods Newsletter, Summer 1988: 5-8 (back)

A. Stewart, K. Prandy and R.M. Blackburn (1973) Measuring the class structure, Nature 245, 5426: 415-417 (back)

A. Stewart and R.M. Blackburn (1975) The stability of structural inequality, Sociological Review 23: 481-508 (back)

A. Stewart, K. Prandy and R.M. Blackburn (1980) Social Stratification and Occupations (Macmillan) (back)

J. Torssander & R. Erikson (2010) Stratification and mortality: A comparison of education, class, status and income. European Sociological Review, 26(4): 465-474 (back)

D. Vågerö (2000) Health inequalities in women and men: studies of specific causes of death should use household criteria, British Medical Journal 320: 1286-1287 (back)

Vermunt, J. K. (1997). lEM : A general program for the analysis of categorical data. Tilburg, Netherlands: Tilburg University. (back)





Software links (software section)



Last modified 7 September 2012
This document was written by Ken Prandy and Paul Lamber. It is maintained by Paul Lambert .