Estimating Expected Individual Treatment Outcomes by Using Nonparametric Evaluation Methods

Consider the situation faced by an individual which has to choose among different treatments available to him. For selecting the optimal treatment he needs to conjecture for each treatment how his situation after treatment would likely to be. This article proposes a semiparametric method to estimate heterogeneous potential treatment outcomes with respect to individual characteristics. These are important in at least two respects. They can be used ex-ante to improve treatment choices and targeting of programmes to heterogeneous individuals. They also allow an ex-post examination whether each individual received the treatment most adequate to him, therewith allowing an assessment of the efficiency of the selection process. While the evaluation literature has mostly concentrated on average treatment outcomes and has promoted nonparametric techniques for their estimation, the systems proposed for targeting programmes have predominantly relied on fully parametric models. The model proposed in this article combines nonparametric and parametric elements into a GMM estimator to attain more robust estimates. Root-n consistency and asymptotic normality are shown. Furthermore, since usually more than one outcome variable is necessary to describe the after-treatment situation, different ways to summarize the numerous estimates, whose number grows quickly with the number of outcome variables and the number of treatments, are considered. Based on the asymptotic distribution of the estimated expected potential outcomes, stochastic dominance probabilities that certain treatments dominate others in one or all outcome variables are derived. Finally the proposed estimator is applied to Swedish rehabilitation programmes.

Teacher Shortages, Teacher Contracts and their Impact on Education in Africa

Primary school enrolment rates are very low in francophone Africa. In order to enhance education supply, many countries have launched large teacher recruitment programmes in recent years, whereby teachers are no longer engaged on civil servant positions, but on the basis of (fixed-term) contracts typically implying considerably lower salaries and a sharply reduced duration of professional training. While this policy has led to a boost of primary enrolment, there is a concern about a loss in the quality of education. In this paper we analyse the impact on educational quality, by estimating nonparametrically the quantile treatment effects for Niger, Togo and Mali, based on very informative data, comparable across these countries. We find that contract teachers do relatively better for low ability children in low grades than for high ability children in higher grades. When positive treatment effects were found, they tended to be more positive at the low to medium quantiles; when negative effects were found they tended to be more pronounced at the high ability quantiles. Hence, overall it seems that contract teachers do a relatively better job for teaching students with learning difficulties than for teaching the ‘more advanced’ children. This implies that contract teachers tend to reduce inequalities in student outcomes. At the same time, we also observe clear differences between the countries. We find that, overall, effects are positive in Mali, somewhat mixed in Togo (with positive effects in 2nd and negative effects in 5th grade) and negative in Niger. This ordering is consistent with theoretical expectations derived from a closer examination of the different ways of implementation of the contract teacher programme in the three countries. In Mali and, to some extent, in Togo, the contract teacher system works more through the local communities. This may have led to closer monitoring and more effective hiring of contract teachers. In Niger, the system was changed in a centralized way with all contract teachers being public employees, so that there is no reason to expect much impact on local monitoring. In addition, the extremely fast hiring of huge numbers of contract teachers may also have contributed to relatively poor performance in Niger. These results are expected to be relevant for other sub-Saharan African countries, too, as well as for the design of new contract teacher programmes in the future.

Compact operators, invariant subspaces, and spectral synthesis

AbstractLet L be a subspace lattice which contains a sequence {Pn} of commuting projections such that for any subsequence {Pni}, VPni = I and ΛPni = 0. Then Alg(L)∩K(H)=0. Suppose G is a compact abelian group and E ⊆ G is a closed set. There is a family LE of commutative subspace lattices for which Alg(LE)∩K(H)≠0 precisely when E is a set of multiplicity in the sense of harmonic analysis. By showing that the graph of ⩽ is a set of uniqueness in 2∞ × 2∞ we obtain a “thin set” proof that Alg(2∞, ⩽, m12) contains no nonzero compact operators.For an important class of sets K ⊆ G × GAmin(K) = Amax(K) iff K is a set of spectral synthesis in the group G X G. It follows that if E1and E2 are sets of spectral synthesis in G then Alg(PE1\̄bo Alg (PE2) = Alg(PE1 ⊗ PE2iff E1 × E2 is a set of spectral synthesis in G X G and if semigroups ∑1 and ∑2 are sets of spectral synthesis in G then Alg(∑1) \̄bo Alg(∑2) = Alg(∑1 × ∑2iff ∑1 × ∑2 is a set of spectral synthesis in G × G. The operator algebra Alg(P1⊗ P2 ⊗ …) is synthetic iff for all n, Alg(P1 ⊗ … ⊗ Pn is synthetic. This implies that the operator algebras Alg(2∞, ⩽, mp) are synthetic

New Competitors for Small Business: The For-Profit Mentality of Nonprofit Organizations

This paper seeks to raise awareness of the increasing competition small business firms are experiencing due to commercialization of the nonprofit sector. The traditional notion of the nonprofit organization is one supported by· donations,  grants, and government funds. However, commercial revenue has grown from 25 percent of total sector income in 1980 to 39 percent by 1996. These statistics suggest the folly of ignoring the for-profit strategies and commercial activities of nonprofit organizations.Characteristics of small business firms and nonprofit organizations are described to highlight their competitive similarities. An empirical exploration of the emerging for-profit mentality of nonprofit organizations suggests that nonprofits are becoming more capable rivals in the competitive marketplace. The paper concludes by considering the implications of this new competition for small business firms