Initial Conditions, Institutional Dynamics and Economic Performance: Evidence from the American States

Using state-level data from the United States, we find that differences in colonial legal institutions affect the current quality of state legal institutions. These differences in colonial legal institutions arose because some states were settled by Great Britain, a common law country, and other states were settled by France, Spain, and Mexico, all civil law countries. To explain these findings, we develop a transplant-civil law hypothesis that highlights the disruption associated with large-scale legal transplantation and the possible relative inefficiencies of colonial civil law. We find strong support for the transplant-civil law hypothesis. Our results are robust to inclusion of additional variables capturing climate, geography, initial population and resource endowments. Given the 150-200 year gap between the initial conditions and the measures of the current quality of legal institutions, we provide indirect evidence on the persistence of legal institutions. We then use initial legal systems and climate to quantify the substantial impact of current institutions on current economic performance.http://deepblue.lib.umich.edu/bitstream/2027.42/40001/3/wp615.pd

Forms of early walking

Children in the first weeks of independent locomotion display a wide variety of walking forms. The walking forms differ in mechanical strategy and concern with balance. Three extreme walking forms are presented: the Twister, who uses trunk twist, the Faller, who uses gravity, and the Stepper, who remains balanced as much as possible. Each walking form is presented as a ''d-space'', a mathematical format combining continuous and discrete aspects, developed to express the sequence and pattern of a movement without the inappropriate precision of a physical trajectory. The three d-spaces represent analyses of three extreme modes of early walking. They are used to generate the variety of early walking forms and to predict mixtures of mechanical strategies as children mature and converge to more similar walking forms over the first few months of independent locomotion. (C) 1995 Academic Press Limite

Absence of long-range superconducting correlations in the frustrated 1/2-filled band Hubbard model

We present many-body calculations of superconducting pair-pair correlations in the ground state of the half-filled band Hubbard model on large anisotropic triangular lattices. Our calculations cover nearly the complete range of anisotropies between the square and isotropic triangular lattice limits. We find that the superconducting pair-pair correlations decrease monotonically with increasing onsite Hubbard interaction U for inter-pair distances greater than nearest neighbor. For the large lattices of interest here the distance dependence of the correlations approaches that for noninteracting electrons. Both these results are consistent with the absence of superconductivity in this model in the thermodynamic limit. We conclude that the effective 1/2-filled band Hubbard model, suggested by many authors to be appropriate for the kappa-(BEDT-TTF)-based organic charge-transfer solids, does not explain the superconducting transition in these materials.Comment: 9 pages, 7 figures. Revised version to appear in Phys. Rev.

Why Is An Inservice Programme For Reading Recovery Teachers Necessary?

The Reading Recovery program was developed in New Zealand to answer the question how can an education system provide a second chance for young children who have not re sponded to the literacy programme in their first year of instruc tion at school? (It is not a program for teaching beginning reading to 80-90% of school children.) There are four aspects to the program: 1) the teaching of children, 2) the training of teachers, 3) the training of teacher leaders, and 4) implement ing the program in an education system and coordinating the long-term prevention strategy. Teachers help children from the lower end of the achievement distribution to participate at or near an average level in their classrooms. Research has demonstrated that the procedures work with children who differ markedly in their prior experience and in their ways of respond ing (Clay, 1982, 1987, 1990, 1991)