Human well-being and causality in social epidemiology

This paper discusses the work of Ballas and Dorling on life events and happiness. I believe epidemiologists have things they could learn from economists (and vice versa). Here I emphasize the issue of how to establish causality, and try to suggest some ways forward

Anomalous magnetotransport in wide quantum wells

We present magneto transport experiments of quasi 3D PbTe wide quantum wells. A plateau-like structure in the Hall resistance is observed, which corresponds to the Shubnikov de Haas oscillations in the same manner as known from the quantum Hall effect. The onsets of plateaux in Rxy do not correspond to 2D filling factors but coincide with the occupation of 3D (bulk-) Landau levels. At the same time a non-local signal is observed which corresponds to the structure in Rxx and Rxy and fulfils exactly the Onsager-Casimir relation (Rij,kl(B) = Rkl,ij(-B)). We explain the behaviour in terms of edge channel transport which is controlled by a permanent backscattering across a system of "percolative EC - loops" in the bulk region. Long range potential fluctuations with an amplitude of the order of the subband splitting are explained to play an essential role in this electron system.Comment: postscript file including 3 figs, 5 page

An assessment of the sportfishery on artificial "Liberty Ship" reefs off Port Aransas, Texas

The concept of using surplus World War II Liberty Ships for the construction of artificial reefs to increase the availability of sportfish off the Texas coast was originally suggested in 1974. It became a reality, under the guidance of the Texas Coastal and Marine Council, when three ships were sunk off Port Aransas in the winter of 1976. Since that time, the ships have rapidly become encrusted with algae, anemones, sea urchins, gorgonian coral and other attached marine life. These in turn have provided refuge and food source for a host of small invertebrates and fishes. In June of 1977, one and a half years after ·sinking the first ship, the Texas Coastal and Marine Council commissioned this study to evaluate the impact of the Liberty Ship reefs on sportfishing in the Port Aransas area. For a project such as the Liberty Ship reefs to be successful, there are two criteria: the ships must increase the supply of desirable sportfish and fishermen must be willing to utilize the new resource. The present study is an attempt to evaluate both aspects of the project. A user survey was conducted to determine the amount and type of recreational usage the Liberty Ships receive.A report to the Texas Coastal and Marine Council in fulfillment of Contract No. IAC(76-77)-2149Submitted September 1977Marine Scienc

The icthyofaunal composition and trophic interactions of the artificial "Liberty Ship" reefs off Port Aransas, Texas

This study is an assessment of the biological effects resulting from the construction of an artificial reef consisting of three surplus Liberty Ships that were sunk off Port Aransas, Texas in 1976. ... Systematic monthly assessment of the Liberty Ship Reefs presented a unique sampling problem. Snagging problems made trawling and other methods of netting unfeasible while depth, turbidity and currents precluded diver transects, baited camera recorders, or hook and line assessments, at least during the winter sampling periods. Fish traps were proposed as a reliable and cost effective means of sampling in all types of weather and sea conditions. Fish traps allow concurrent sampling of open bottom areas and reef with the same ship, making possible a true comparison of the relative productivity of artificial reefs. They also allow consistent day-night sampling and seasonal replication without the inherent variations in skill that bias diver transects and hook and line assessments. This initial report describes the construction and deployment of traps and summarizes the data collected during January-February sampling cruises. These initial sampling cruises indicate that fish traps are a practical method of assessing the productivity of the artificial "Liberty Ship" reefs.Winter seasonal report submitted to the Texas Coastal and Marine Council in partial fulfillment of IAC (78-79)--0869Submitted March 1978Marine Scienc

Species composition and ecological relationships of icthyofauna on artificial Liberty Ship reefs off Port Aransas, Texas : final report submitted to the Texas Coastal and Marine Council in partial fulfillment of IAC (78-79)-0869

Submitted August 1978Five cruises were made to the Liberty Ship Reef off Port Aransas, Texas in June and July 1978. Collecting procedures, which included sampling by fish trap, hook and line, and long line, were relatively unchanged from previous trips. Increased diver participation allowed more reliable placement of the traps onto the deck of the ships. Diver observations of fish greatly supplemented other data collecting methods. Fishes collected or observed on the ship reef were divided into four ecological groups: 1) obligate reef fishes which are demersal and almost always associated with natural or artificial structures, 2) coastal pelagic species which are attracted to structures for orientation, 3) estuarine-dependent opportunistic species which exploit the reef for food and shelter but are not confined to that habitat, 4) typical continental shelf species which occur near the ship reef but are not actually associated with it. At this time of year the Liberty Ship reefs support a large and diverse fish fauna, composed of both predator and prey species, and appears to have many characteristics of a complete reef habitat with an abundance of catchable sportfish.Marine Scienc

Microscopic details of stripes and bubbles in the quantum Hall regime

We use a fully self-consistent laterally resolved Hartree-Fock approximation for numerically addressing the electron configurations at higher Landau levels in the quantum Hall regime for nearmacroscopic sample sizes. At low disorder we find, spatially-resolved, stripe- and bubble-like charge density modulations and show how these emerge depending on the filling factor. The microscopic details of these boundary regions determine the geometrical boundary conditions for aligning the charge density modulation either as stripes or bubbles. Transport is modelled using a non-equilibrium network model giving a pronounced anisotropy in direction of the injected current in the stripe regime close to half filling. We obtain a stripe period of 2.9 cyclotron radii. Our results provide an intuitive understanding of its consequences in strong magnetic fields and indicate the dominance of many particle physics in the integer quantum Hall regime when studied at legnth scales

Daughters and Left Wing Voting

What determines human beings' political preferences? Using nationally representative longitudinal data, we show that having daughters makes people more likely to vote for left-wing political parties. Having sons leads people to favor right-wing parties. The paper checks that our result is not an artifact of family stopping-rules, discusses the predictions from a simple economic model, and tests for possible reverse causality.Voting, gender, daughters, political preferences, attitudes.

Are People Willing to Pay to Reduce Others' Incomes?.

This paper studies utility interdependence in the laboratory. We design an experiment where subjects can reduce ("burn") other subjects' money. Those who burn the money of others have to give up some of their own cash. Despite this cost, and contrary to the assumptions of economics textbooks, the majority of our subjects choose to destroy at least part of others' money holdings. We vary experimentally the amount that subjects have to pay to reduce other people's cash. The implied price elasticity of burning is calculated; it is mostly less than unity. There is a strong correlation between wealth, or rank, and the amounts by which subjects are burnt.INCOME ; MONEY ; PRICES

Conductance Fluctuations in PbTe Wide Parabolic Quantum Wells

We report on conductance fluctuations which are observed in local and non-local magnetotransport experiments. Although the Hall bar samples are of macroscopic size, the amplitude of the fluctuations from the local measurements is close to e^2/h. It is shown that the fluctuations have to be attributed to edge channel effects.Comment: postscript file including 3 figs, 3 pages, Paper presented at 3rd Int. Symposium on "New Phenomena in Mesoscopic Structures" in Maui, Hawaii 199