Many economists and policy makers believe that education creates positive externalities. Indeed, average schooling in U.S. states is highly correlated with state wage levels, even after controlling for the direct e¤ect of schooling on individual wages. We use variation in child labor laws and compulsory attendance laws over time and across states to investigate whether this relationship is causal. Our results show private returns to education that are around 7 percent, and external returns to education that are in the neighbourhood of 1-2 percent and not signi…cantly di¤erent from zero.

Abstract not found

Dissertation zur Erlangung des akademischen Grades Dr. rer. nat.

Updated information and services can be found at:

The gall crab Fizesereneia tholia Kropp, 1994 (Cryptochiridae) was described based on a single ovigerous female from material collected during the Rumphius I expedition in 1973 in the Moluccas (Indonesia). This species was encountered on

All children are essentially criminal. (Diderot, 1713-1784) A child is a curly, dimpled lunatic. (Ralph Waldo Emerson, 1803-1882) Having children is like having a bowling ball installed in your brain. (Martin Mull, 1978)

Under the educational sorting hypothesis,an environment in which some individuals are constrained from entering university will be characterized by increased pooling at the highschool graduation level, as compared toanenvironmentwithgreateruniversityaccess. Thisresultsbecausesomepotentialhighschooldrop-outs and university enroleeschoose the high schoolgraduate designationinorder to take advantage ofhigh abilityindividualswhoareconstrainedfromentering university. Thisisinstarkcontrasttohumancapital theorywhichpredictshigheruniversityenrolment, butidenticalhighschooldrop{outratesinregionswith greateruniversityaccess.Itestthecontradictoryhighschool drop-outpredictionsofthehumancapitaland signalingmodelsusingNLSYM and NLSYW educationdata from the late 1960sand early1970s. I find that labor markets thatcontainuniversitieshavehigherhighschooldrop{outrates. Thisresultisconsistent withasignalingmodel, andinconsistentwithapurehumancapitalmodel.

We present an automated multilevel substructuring (AMLS) method for eigenvalue computations in linear elastodynamics in a variational and algebraic setting. AMLS first recursively partitions the domain of the PDE into a hierarchy of subdomains. Then AMLS recursively generates a subspace for approximating the eigenvectors associated with the smallest eigenvalues by computing partial eigensolutions associated with the subdomains and the interfaces between them. We remark that although we present AMLS for linear elastodynamics, our formulation is abstract and applies -elliptic bilinear forms.

Gender stereotypes—the features and characteristics assigned to men and women in a particular society—are preva-lent in children as young as the preschool years (Martin and Ruble, 2004). For exam-ple, preschoolers can categorize toys as appropriate for either girls (e.g., dish-set) or boys (e

We introduce Membrane, a set of changes to the operating system to support restartable file systems. Membrane allows an operating system to tolerate a broad class of file system failures and does so while remaining transparent to running applications; upon failure, the file system restarts, its state is restored, and pending application requests are serviced as if no failure had occurred. Membrane provides transparent recovery through a lightweight logging and checkpoint infrastructure, and includes novel techniques to improve performance and correctness of its fault-anticipation and recovery machinery. We tested Membrane with ext2, ext3, and VFAT. Through experimentation, we show that Membrane induces little performance overhead and can tolerate a wide range of file system crashes. More critically, Membrane does so with little or no change to existing file systems thus improving robustness to crashes without mandating intrusive changes to existing file-system code. 1