Relationships between set-out rate, participation rate and set-out quantity in recycling programs

The most often used indicators fbr participation in recycling programs are the set-out rate, the participation rate and the quantity of recyclables per recycler. The participation rate, measured from the set-out rate over a period of time, is often used to estimate the amount of recyclables to be collected. However, the behavioural mechanisms that underlie the set-out rate, and hence the participation rate and the estimation of amount of recyclables collected, are largely unknown. This paper briefly evaluates the factors contributing to public participation in recycling programs and discusses the factors influencing set-out rate and set-out frequency. The effective participation rate is introduced as the ratio of the amount of recyclables collected to the amount of recyclables generated. The relationships between the set-out rate, the participation rate as measured over a period time, and the amount of recyclables collected as measured through the effective participation rate, are simulated on the basis of two hypotheses for behavioural mechanisms. The simulation shows that a meaningful period for determining the effective participation rate largely depends on the relative storage capacity. The larger the storage capacity compared with the generation of recyclables, the longer the period that should be used to estimate the effective participation rate to predict more accurately the amount of recyclables collected. This paper provides a basis for further research by offering some insight into participation behavioural mechanisms. (C) 1997 Elsevier Science B.V.