General Limited Enthusiasm Model with Births Deaths and Reversion
Basic Assumptions Summary   Questions What is meant by "Spreading the Faith"? Why Do People leave the Church? How do the children of believers become part of church? Why do the children of believers fail to become part of church?   Technical Details for the General Limited Enthusiasm Model Systems Dynamics Model Equations Parameters Results   Details of Models Limited Enthusiasm  Births, Deaths & Reversion  Renewal   Details of Results Summary of Results Short Term Revival  Long Term Growth Long Term Decline Growth via Renewal   References & Bibliography  Mathematics of Church Growth Church Growth  Revival  System Dynamics  Sociology of Religion Epidemics  Social Diffusion Publications Articles Models for Download	Basic Assumptions of the General Limited Enthusiasm Model The model consists of four groups of people: unbelievers, active believers (or enthusiasts) who alone are responsible for spreading the faith, inactive believers, and hardened unbelievers. For simplicity all church members are assumed to be believers and vice versa. It is further assumed that members are identical with the attenders of the church. Thus is further explained in the assumptions for the limited enthusiasm model. Hardened unbelievers are believers who have dropped out of the church who temporarily remain immune to be recruited back into the church by enthusiasts. The model is a generalised version of the Limited Enthusiasm model enabling it apply over long periods of time. As such it allows for births, deaths and believers abandoning the church - called reversion. Return to Top Summary of the General Limited Enthusiasm Model Unbelievers convert to believers through contact with active believers who have "spread the faith" to them. Some new converts are become active believers whereas some become inactive believers. Active believers only remain active for a limited length of time before becoming inactive and taking no further part in spreading the faith. Both types of believers may revert back to unbelievers however they spend a period hardened to conversion back into the church. After a period of time they soften and become unbelievers who can be recruited into the church again. In addition some of the children of both types of believers may fail to even join the church in the first place. Also not all the children of active believers who join the church are themselves active. Return to Top What is meant by "Spreading the Faith"? All aspects of conversion and spreading the faith are discussed in the limited enthusiasm model. Return to Top Why do people leave the church? People leave the church for many reasons. Some renounce the faith and return to the world. Some still claim to be Christian but no longer attend church. This model does not make any spiritual judgment on those that leave church, in the same way as it makes no assumptions of those who belong. Reasons for people leaving church include: 1 Physical persecution. At its most extreme believer's lives could be in danger, as frequently happened in the early church. Christians would be asked to swear allegiance to Caesar and curse Christ, or face death. Those who succumbed were no longer welcomed in the church. The fear of this test caused many others to renounce the faith also. 2 Psychological persecution. Some believers give up the faith due to pressure of unconverted family or peers. The pressure may take the form of teasing or being shunned from normal social activities. The believer gives up the church to have an easier life. 3 Some of the believers were not truly converted in the first place and give up the faith once it loses its initial attraction. The unbelieving world they left behind has proved more attractive to them. 4 The believer may have fallen into sin and caused them to be to ashamed to be part of the church anymore. 5 The believer may have been hurt by others in the church. It is now too painful for them to be part of the church with those who hurt them. Sometimes it is to painful to be in any church as it reminds them of the past hurt. Return to Top How do the children of believers become part of church? Children are not normally born with a faith. However if a child is brought up in the Christian faith it is the hope of Christian parents that they will believe for themselves and join the church. This is often called biological growth to distinguish it from conversion growth. Of course the children at some point should become converted! However their conversion has taken place within the Christian community rather than from the world outside. In this model such children will be regarded as being "born as believers". There is a time lag between birth and the formal adoption of such children into the church. This time lag will vary according to church policy - anything from aged 6 to 18! It will also vary depending on whether the model is compared with attendance, membership or communicant figures. In this model this time lag is ignored. Return to Top Why do the children of believers fail to become part of church? Again numerous reasons.  1 Some are not converted and thus see no reason for belonging to the church. Although familiar with the church's culture spiritually it is meaningless to them.  2 Some churches offer so little that even converted children see little point in joining. However the absence of Christian friends does not enable them to easily join another church which is a huge step for a young person.  3 Young people are very sensitive to hypocrisy. Both perceived and actual hypocrisy in the adult generation will cause young Christians to prefer to be believers "who do not attend church". Return to Top Systems Dynamics Model for the General Limited Enthusiasm Model Any system dynamicists viewing this site might be interested in the Stella version of the limited enthusiasms model. Further explanation is available at the Modelling and Analysis research page, University of Glamorgan. Just follow the link to Church Growth Modelling. A Stella version of this model is available for download. Return to Top Equations of the General Limited Enthusiasm Model These and other technical information are available at the Modelling and Analysis research page, University of Glamorgan. Just follow the link to Church Growth Modelling. Return to Top Parameters 1 The reproduction potential. This is the number of unbelievers converted and made enthusiasts through one existing active believer (enthusiast). It measures how much an enthusiast can "reproduce" themselves out of the pool of unbelievers. It is composed of two independent parameters: The potential number of people converted through one active believer during their enthusiastic phase - the conversion potential. The fraction who become active believers on conversion rather than inactive. 2 The duration of the enthusiastic phase. 3 The fraction of children of inactive believers who leave the church before an adult commitment. 4 Likewise the fraction of children of active believers (enthusiasts) who leave the church. 5 The fraction of children of active believers who also become active in recruitment. 6 The rates at which adult believers, both active and inactive leave the church. 7 The average length of time a believer who has left the church remains hardened to reconversion or restitution. Return to Top Results of the General Limited Enthusiasm Model There are implications for the long-term growth of the church and its long-term decline. Like the limited enthusiasm model there is a revival-type growth threshold over which the church will see rapid growth. However there is also an extinction threshold under which the church will decline to no members or attenders.