New Constraints on Isospin-Violating Dark Matter

We derive bounds on the dark matter annihilation cross-section for low-mass (5-20 GeV) dark matter annihilating primarily to up or down quarks, using the Fermi-LAT bound on gamma-rays from Milky Way satellites. For models in which dark matter-Standard Model interactions are mediated by particular contact operators, we show that these bounds can be directly translated into bounds on the dark matter-proton scattering cross-section. For isospin-violating dark matter, these constraints are tight enough to begin to constrain the parameter-space consistent with experimental signals of low-mass dark matter. We discuss possible models that can evade these bounds.Comment: 6 pages, 2 figures, LaTeX, some clarifications and minor errors corrected, citations adde

The Level and Persistence of Growth Rates

Expected long-term earnings growth rates are crucial inputs to valuation models and for cost of capital estimates. We analyze historical long-term growth rates across a broad cross-section of stocks using several operating performance indicators. We test whether growth persists, and whether it is forecastable. Cases of very high growth have occurred, but are relatively rare. There is scant persistence in growth beyond chance, and limited ability to identify firms with high future long-term growth. IBES forecasts are too optimistic, and have low predictive power for long-term growth. Regressions using a variety of predictors confirm the low predictability in growth. Valuations that assume persistently high growth over prolonged periods rest on shaky foundations.

Evaluation of Leaching Protocols for the Testing of Coal Combustion Byproducts

Beneficial reuse of coal combustion byproducts requires an evaluation of metal leaching potential. Reuse of high carbon fly ash in highway embankment construction was evaluated using different soil-fly ash mixtures and three common leaching tests: the water leach test (WLT), the Toxicity Characteristic Leaching Procedure (TCLP), and the column leach test (CLT). The effect of test methodology and pH on Cu, As, and Cr leaching was examined. TCLP concentrations for Cu and As exceeded those from WLTs in the majority of mixtures due to lower pH conditions, while Cr was higher in the WLT for alkaline fly ash mixtures. Peak CLT concentrations were higher than TCLP and WLT concentrations for the majority of mixtures, but usually decreased rapidly, suggesting that leachate concentrations might exceed regulatory limits, but only for a short time. Based on these results, a combined WLT and CLT leaching protocol for testing fly ash mixtures is presented

TWENTY-FIRST CENTURY WOODLAND ARCHAEOLOGY IN THE LOWER ILLINOIS RIVER VALLEY: A REGIONAL MODEL

The Lower Illinois River Valley (LIV) has been the subject of over a century of focused archaeological inquiry, resulting in robust body of data with which to investigate the lifeways of ancient indigenous peoples of midcontinental North America. Among the most visible components of this record are the Middle Woodland (50 cal BC-cal AD 400) and Late Woodland (cal 400-1000) assemblages that document an extended period of significant social and demographic transformation of the valley, marked by highly visible monumental architecture, e.g. mounds, and often complex mortuary practices culminating in the disposal of the dead with these monuments. Research reported in this dissertation addresses several outstanding questions concerning Woodland period settlement, moundbuilding and monumentality, mortuary practices, kinship, and ideology during the LIV Woodland period. First, radiometric data from habitation and mound sites are used to test models of LIV settlement between ca. 50 cal BC and cal AD 400. Analyses show the conventional model of north-to-south LIV settlement is generally supported by mortuary radiocarbon dates, but it is not wholly supported by dates from associated habitation sites. Existing data do not readily support intrasite chronologies at selection mound sites as well. Results indicate that LIV settlement was more complex than suggested by existing models and demonstrate the need for more robust models and datasets. Second, moundbuilding and monumentality are investigated using a geophysical approach. Results from several geophysical surveys of LIV Middle Woodland mounds using multiple instruments demonstrate the utility of this approach in the non-invasive investigation of internal mound structure. The geophysical work reported here is the first application to LIV mounds, and it points to new directions for the anthropological study of LIV mounds through non-invasive methods. Finally, a bioarchaeological/biological distance approach is employed to investigate Woodland period mortuary practices, kinship, and ideology between ca 50 cal BC and cal AD 1000. Two studies are reported, one regional and one intrasite, that document interrelationships between community membership, post-marital residency, kinship, and ideology. Results demonstrate Woodland period mortuary practices were an important process through which kin groups/lineages established and legitimized existing social relations within communities

Analysts' Conflict of Interest and Biases in Earnings Forecasts

Analysts' earnings forecasts are influenced by their desire to win investment banking clients. We hypothesize that the equity bull market of the 1990s, along with the boom in investment banking business, exacerbated analysts' conflict of interest and their incentives to adjust strategically forecasts to avoid earnings disappointments. We document shifts in the distribution of earnings surprises, the market's response to surprises and forecast revisions, and in the predictability of non-negative surprises. Further confirmation is based on subsamples where conflicts of interest are more pronounced, including growth stocks and stocks with consecutive non-negative surprises; however shifts are less notable in international markets.