Ball Response and Traction of Skinned Infields Amended with Calcine Clay at Varying Soil Moisture Contents

The skinned portions of baseball and softball infields vary widely with respect to soil texture, applied amendments and conditioners, and water management. No studies have been reported that quantify the effects of these varying construction and maintenance practices on the playability of the skinned portions of infields. In Connecticut, USA, skinned infield plots were constructed from five different soils (silt loam, loam, coarse sandy loam, loamy sand, loamy coarse sand) and amended with four rates of calcined clay (0, 4.9, 9.8, 19.6 kg m–2) to determine the effects on surface hardness, traction, and ball-to-surface friction (static and dynamic) at varying soil moisture contents (10, 14, and 18%). Bulk density, saturated hydraulic conductivity, and shear strength of the different soil–calcined clay rate combinations were determined. Increasing the rate of calcined clay decreased bulk density and shear strengths, and increased saturated hydraulic conductivity. Surface hardness increased more with coarse-textured soils and increasing calcined clay rate, but decreased more with fine-textured soils and increasing soil moisture. Increasing the calcined clay rate resulted in decreases in ball-to-surface static friction across all soils and decreased dynamic friction with the fine-textured soils. Increases in soil moisture increased friction in all soils. The fine-textured soils had greater traction than the sandy soils, but no consistent calcined clay or moisture effects on traction were observed. Shear strength of the soils was highly correlated with traction and friction. The results suggest that differences in skinned infield soils are quantifiable, which could lead to the development of playing surface standards.

Dynamic Stock Market Interactions between the Canadian, Mexican, and the United States Markets: The NAFTA Experience

This paper explores the dynamic linkages that portray different facets of the joint probability distribution of stock market returns in NAFTA (i.e., Canada, Mexico, and the US). Our examination of interactions of the NAFTA stock markets considers three issues. First, we examine the long-run relationship between the three markets, using cointegration techniques. Second, we evaluate the dynamic relationships between the three markets, using impulse-response analysis. Finally, we explore the volatility transmission process between the three markets, using a variety of multivariate GARCH models. Our results also exhibit significant volatility transmission between the second moments of the NAFTA stock markets, albeit not homogenous. The magnitude and trend of the conditional correlations indicate that in the last few years, the Mexican stock market exhibited a tendency toward increased integration with the US market. Finally, we do note that evidence exists that the Peso and Asian financial crises as well as the stock-market crash in the US affect the return and volatility time-series relationships.