2. ANTECEDENTES DE LA INVESTIGACION
3.4. VALIDACIÓN DE INSTRUMENTO
Having more aspirational individuals in the population increases the income of everyone either directly or through redistribution. However, this ignores the possibility that an economy could have more of a tournament-like struc- ture in the way that rewards are allocated and where the e¤orts of other members of the society reduce the probability that an individual becomes a high income individual. Thus putting in e¤ort is in part a “rat race”where a few winners take all the rewards. We will now extend the model to in- corporate this possibility and to explore its implications for the conclusions reached so far. There is now an additional externality in the model so it simpli…es things to focus on the case where redistribution is given exoge- nously at and de…ne Z = (1 ) [aH aL]. This eliminates the political
externality which has been the main driving force linking e¤ort decisions so far and allows us to focus on the implications of our di¤erent model of the economy.
To capture the idea of a rat race formally, suppose that there is an upper bound on the fraction of high income jobs set at < 1. If the proportion
of individuals who achieve exceeds the number of slots available, i.e. e > then they are allocated a high income job with probability =e = . To simplify matters further, the analysis will focus on the case of a quadratic cost of e¤ort (1=2) e2.
Then the optimal e¤ort level is e = min f ; 1g Z which yields an equilibrium e¤ort level for society as a whole of
e ( ) = (
Z if = Z q
Z otherwise.
The case where > = Z is where the rat race kicks in since e¤ort per capita is lower if the fraction of aspirational individuals increases, i.e. there is now a negative externality from having more aspirational individuals in the population. In spite of this, however, total e¤ort, e ( ), is increasing in in a rat race even though more aspiration does not lead to there being more high income individuals in the population. Thus, if > = Z, the economy resembles a rent-seeking contest for a scarce set of rewards.
Now consider the gains from being an aspirational individual in this mod- i…ed economy. This will depend on whether is high enough to induce a rat race. Hence18:
( ) = ( 1 2 Z 2 + Z Z 1 if = Z Zh 1 + 2 i otherwise.
An immediate observation from this is 0( ) < 0 whenever > = Z so
having more aspirational individuals in the population reduces the return to being aspirational since it increases the intensity of the rate race. This has rather di¤erent implications for the dynamics of aspiration compared to the core model of the previous section. Speci…cally:
Proposition 8 If Z 1 + 2 > 1 > 1 + 2 , then the economy converges globally to an interior equilibrium where the fraction of aspirational individ- uals ^ = 1 + 2 2 (0; 1).
18To see this observe that the probability that a high aspirations individual achieves
high income is
e
e = when > = Z.
Proof. As in the core model, the dynamics will be governed by t+1 t=
(1 ) t(1 t) [2 ( ( t)) 1]. Under the condition in the Proposition, (0) > 0 > (1) and there is a unique value of at which (^) = 0. Moreover t+1 ^ = (1 ) ^ (1 ^) [2 ( (^)) 1] = 0with t+1 t > 0
for all t < ^ and t+1 t < 0 for all t > ^. Thus there is global
convergence to ^ for all 2 [0; 1].
The reasoning behind this is fairly straightforward. Under the stated condition, there is gain to being aspirational when there is no rat race, e.g. = Z. However, eventually (for high enough ) the rat race begins and being aspirational is less worthwhile. Eventually, the rat race is so intense that individuals are worse o¤ being aspirational. The point at which the gains to be an aspirational type are zero is then a stable point. It is easy to see that the interior point is decreasing in ; the loss aversion parameter and increasing in , the potential fraction of high income jobs.
The possibility of a rat race also has consequences for the welfare eco- nomics of aspirational societies since the welfare of the aspirational type is positive as long as there is no scarcity of high income jobs. However, once high income jobs become scarce, i.e. > = Z, then creating more aspira- tional types leads to an excessive aggregate e¤ort level as individuals strive to capture these high-income positions while ignoring the negative externality that they are imposing on others.
In summary, this section has emphasised that there is a somewhat funda- mental di¤erence between two kinds of economies when assessing the role of aspirations. If the opportunities for aspirational individuals are not intrin- sically scarce, then encouraging aspiration has positive consequences. How- ever, if such opportunities are rationed, this is less clear-cut. In practice, there are elite positions in society such as access to certain universities and jobs, which have not expanded materially over time and, for which the idea of an aspirational rate race would seem relevant. It would, of course, be possible to combine the analysis of an externality coming through a rat race e¤ect together with the externality coming through endogenous redistribu- tion. This would complicate things since the direction of the externality would be unclear a priori. However, the possibility of aspirational individu- als inducing a rat race would remain an important caveat to the analysis.