The Motivational Strength of Salary Bonuses: A Conjoint Experiment

• In Event: Survey Experiments in Educational Research: International Perspectives on an Innovative Research Methodology

Abstract

Objective
We assess how important are salary bonuses in determining teachers’ motivation compared with other types of motives and explore to what extent teachers in contexts where salary bonuses already exist, give less importance to intrinsic motives.

Perspective
In some contexts, salary bonuses have been introduced to reward teachers whose students have performed better – or have shown better progression – in the national standardized test. The idea behind is that the perspective of gaining a bonus stimulate teachers’ motivation and consequently foster the quality of their teaching. However, looking at behavioral sciences literature, it is yet not clear whether these kinds of material incentives really have the potential of fostering teachers’ motivation.
Behavioral scientists have longer distinguished between two different types of motivation: extrinsic and intrinsic (White 1959; Deci, 1971). The first type is at stake when an individual performs a behavior “to satisfy an external demand or obtain an externally imposed reward contingency” (Ryan and Deci 2000, 61). Intrinsic motivation, on the contrary, is a motivation which is self-determined, i.e. coming from within the individual. This means that the engagement in a behavior is motivated by personal desire, the enjoyability of the experience, the self-satisfaction in performing a behavior, etc., independently from external factors. Already in the 1970s, research has shown that external rewards and prizes can undermine engagement in people who are already intrinsically motivated (Deci, 1971; 1972a; 1972b). This is particularly relevant in the case of teachers. Literature has indeed longer argued that teachers are principally intrinsically motivated (Lortie, 1975; Johnson, 1986; Firestone and Pennell, 1993). As a consequence of the increased importance of accountability policies in education, an amount of studies has suggested that financial incentives also can become motivational forces for teachers (Elmore, 2004; Leithwood et al., 2002; Mintrop and Ordenes, 2004). Nonetheless, it remains not clear whether they can hamper intrinsic motives.

Methods
We use a novel experimental conjoint design. This is a tool of causal inference that allow estimating the causal effects of multiple treatment components and simultaneously assess several causal hypotheses (Hainmueller et al. 2013).

Data source
The experiment has been embedded in a teachers’ survey administrated in a representative sample of schools in countries with different test-based accountability policies (Chile, the Netherlands, Norway, Spain).

Results
The results provide evidence on the extent to which the introduction of extrinsic incentives to compensate adverse working conditions, such as struggling learning environments, unsupportive colleagues or job precariousness. They also show how, in some cases, working environments which foster the development of the teaching skills compensate extrinsic incentives linked to test-based assessments.

Significance of the study
The paper explores for the first time how incentives are perceived by teachers in multidimensional scenarios. The empirical approach followed also overcome the limits of direct questioning regarding the uni-dimensionality and the potential desirability bias. This could be inspiring for future research. From the policy point of view, it allows a discussion on the policy implications of the introduction of extrinsic incentives.

Authors

• Gerard Ferrer-Esteban, Universitat Oberta de Catalunya

• Antonina Levatino, Universitat Autònoma de Barcelona

• Antoni Verger, Universitat Autònoma de Barcelona