The paper provides a theoretical model and an empirical analysis on volunteering, which takes into account the overlapping motivations of consumption (intrinsic) and investment (extrinsic). The analysis shows that intrinsic motivation has a positive effect on the likelihood of volunteering and that volunteering is also related to household composition, depending on other time constraints (people in the workforce or outside it).  

1.   Issues on volunteering

Many studies have attempted to explain the supply of voluntary work using two main theoretical frameworks: one based on a consumption hypothesis, the other on investment perspectives. In the model of "private consumption", the volunteer is motivated to give by itself and time spent in voluntary work has no other extrinsic payoff that others’ satisfaction. Therefore, the consumption hypothesis implies other regarding preferences, classified as a category of intrinsic motivation (Deci 1971) by Meier and Stutzer (2008). In the investment approach, volunteering improves human capital, increases employability and future income (Menchik, Weisbrod 1987). In that case, volunteering payoffs are extrinsic and involve individualistic preferences.

Only a few works  explicitly consider the role of intrinsic motivation in the individual choice of supply of unpaid work (Cappellari, Turati 2004; Cappellari et al. 2007; Meier, Stutzer 2008), although altruistic reasons are, on average, more important than the individualistic ones in offering voluntary work (Hwang et al. 2005; Clary et al. 1996).

Time devoted to volunteering is subtracted from both work and leisure, and it is used for others’ welfare, just as with family care duties. The relationship between family duties and volunteering is twofold: on the one hand, the presence of young children or the elderly needing care influences the amount of voluntary labour supplied (Taniguchi 2006) because the need for care within the family modify the opportunity set available to the volunteer (Cappellari et al. 2007); on the other hand, time devoted to family care pursues the same altruistic motivation of volunteering.

2.   The model

Using a Cobb Douglas with constant returns in the type of motivation, the model assumes that the individual engages in activities that do not bear another benefit but the activity itself only if a positive intrinsic motivation is at work. When intrinsic motivation occurs, the individual utility  depends positively on time spent in family care activities and time spent in voluntary activities outside the family, being the two perfectly substitutable. Moreover, individuals outside the workforce pursue a consumption objective while, for those in the workforce, the consumption motivation can coexist with an investment target.

In equilibrium, given a positive intrinsic motivation, the amount of voluntary work supplied by individuals belonging to the labour force depends on household duties and on non labour  income; for people outside the labour force, it depends only on intrinsic motivation with a stronger effect. Due to investment motives, voluntary activity is inversely related to age, only for the labour force.

3.   Empirical strategy and results

The empirical analysis, performed on data from the National Institute of Statistics (Multiscopo survey for 1997), uses a Probit specification on frequent volunteering. Results show that the intrinsic motivation influences, in the expected direction, the likelihood to carry out voluntary work for once or more times a week, both for workers and for those outside the workforce.

In more detail, intrinsic motivation influences positively the probability of making a voluntary activity for those belonging to labour force and the variables relating to family have the significance and sign to be expected. Age dummies indicate a negative relationship with the likelihood of doing volunteer work frequently.

For those outside the labour force, the greater impact of intrinsic motivation supports the hypothesis that only the consumption pattern works. Moreover, income and family obligations do not affect the likelihood of doing voluntary work.

Robustness analysis was carried out, using a Logit specification and then introducing dummies regarding activity sector. Activities requiring more specific skills (education, health care and social services) give stronger results as compared to activities with more general skills.

4.   Main findings discussion

The implications arising from the theory have suggested the splitting of the sample of volunteers into two subgroups: individuals belonging to the labour force and those outside it. Although the abstract definition of intrinsic motivation and the absence of a well-established literature, empirical analysis confirms an important role for intrinsic motivation, especially for individuals outside the labour force compared to those who participate actively in the labour market.

The theoretical predictions identify a different set of variables determining the supply of volunteer labour, depending on whether the volunteer belongs or not to the labour force. These predictions are confirmed by empirical analysis. Under the assumption of different motivations for those outside or within the workforce, the empirical evidence confirms that the investment model can be assessed only for the labour force component.

Assuming perfect substitutability between home-based care and voluntary activities, impact of the household responsibilities differs between subjects inside or outside the workforce. Results support that voluntary choices are influenced by family obligations only for those participating in the labour market.

Although no cases have been modelled on the role of business sector, the data show a positive and significant effect of these variables on volunteering. The significant impact of skills specific sectors suggests that, for those active in the labour market, voluntary activity could be encouraged by the possibility of expanding the network of social relations and / or to accumulate human capital in specific sectors, confirming, in turn, the investment perspective for those active in the labour market.