Random Utility Models of Recreational Fishing: Catching Fish Using a Poisson Process

This paper presents a Poisson model of expected angler catch during a sportfishing trip and employs the expected catch in a random utility model of site choice. The approach permits greater heterogeneity in expected catch and in individual welfare estimates from policies such as creel limits.sportfishing, creel limits, expected catch, Environmental Economics and Policy, Resource /Energy Economics and Policy,

Principles of a developmental reading program applied to Rossville Grade School

Call number: LD2668 .R4 1966 H45

Prospective Early Childhood Teachers’ Evolving Conceptions of Using a Mathematics Learning Trajectory to Guide Intentional Teaching

This qualitative, phenomenological study investigated how fifteen early childhood preservice teachers’ (PSTs) mathematical knowledge needed for teaching and early mathematics learning trajectory knowledge impacted the intentionality of instructional decision-making. The central research question asked: In what ways do early mathematics learning trajectories inform prospective early childhood teachers’ instructional decisions in ways that are likely to advance student learning on the subitizing trajectory? The literature review revealed numerous studies focused on the usefulness of learning trajectory knowledge on prospective elementary and inservice teachers’ mathematical knowledge for teaching, lesson planning, instruction, and assessment, but no studies were found regarding early childhood pre-service teachers’ understanding of an early mathematics learning trajectory to guide intentional instructional decision-making. A semi-structured interview protocol with stimulus texts was designed to elicit early childhood PSTs’ understanding of subitizing, the subitizing trajectory, and the influence of each on their instructional decision-making. Five themes emerged from the analysis of this data offering insights into the intentionality of early childhood PSTs’ decision-making to advance student learning: (1) demonstrates an understanding of subitizing, (2) recognizes and validates the importance of subitizing for young children, (3) articulates learning trajectory progression through dot arrangements, (4) demonstrates an awareness of the developmental nature of children’s mathematical thinking, and (5) centers instructional decisions on children’s thinking. Findings from this study suggest early childhood PSTs (a) demonstrated a keen interest in understanding children’s thinking and were capable of crafting instructional opportunities that aligned with the subitizing learning trajectory, (b) developed a complex and nuanced understanding of the subitizing trajectory, and (c) engaged in a cycle of instructional decision-making highlighting an intricate relationship between subject matter knowledge, pedagogical content knowledge, and learning trajectory knowledge

Dynamic facilitation explains democratic particle motion of metabasin transitions

Transitions between metabasins in supercooled liquids seem to occur through rapid "democratic" collective particle rearrangements. Here we show that this apparent homogeneous particle motion is a direct consequence of dynamic facilitation. We do so by studying metabasin transitions in facilitated spin models and constrained lattice gases. We find that metabasin transitions occur through a sequence of locally facilitated events taking place over a relatively short time frame. When observed on small enough spatial windows these events appear sudden and homogeneous. Our results indicate that metabasin transitions are essentially "non-democratic" in origin and yet another manifestation of dynamical heterogeneity in glass formers.Comment: 6 pages, 6 figure

Decorah Ice Cave State Preserve

The Ice Cave at Decorah, Iowa, is the largest known glaciere in North America east of the Black Hills and the subject of much international speculation during the latter half of the nineteenth century. A satisfactory theory for the formation of ice in late spring in this and other caverns was first proposed by Alois Kovarik after a series of meteorological measurements. Recent observations confirm his hypothesis. Because of its historical and geological interest and because it is the habitat of insects found nowhere else in North America, it has recently been included in the Iowa State Preserves System

Multi-kilowatt modularized spacecraft power processing system development

A review of existing information pertaining to spacecraft power processing systems and equipment was accomplished with a view towards applicability to the modularization of multi-kilowatt power processors. Power requirements for future spacecraft were determined from the NASA mission model-shuttle systems payload data study which provided the limits for modular power equipment capabilities. Three power processing systems were compared to evaluation criteria to select the system best suited for modularity. The shunt regulated direct energy transfer system was selected by this analysis for a conceptual design effort which produced equipment specifications, schematics, envelope drawings, and power module configurations

Tres especies nuevas de Pristimantis (Lissamphibia: Anura) en los bosques montanos de la Cordillera Yanachaga en el centro del Perú

We describe three additional new species of Pristimantis from the Cordillera Yanachaga, a part of the Andes in central Peru. Analyses of DNA sequences of the mitochondrial rRNA genes show that one species is a close relative of P. bipunctatus (P. conspicillatus Group), another is a close relative of P. stictogaster (P. peruvianus Group), and the third is related to several species in the P. unistrigatus Group. The first two species are morphologically similar to their closest relatives but occur at lower elevations. Twenty-nine species of Pristimantis and Phrynopus are known from the vicinity of the Cordillera Yanachaga. The number of species, especially of Pristimantis, is high in the humid montane forest in comparison with other sites in humid montane forests in Peru, but the number is lower than on the western slopes of the Andes in Ecuador.Describimos tres especies nuevas de Pristimantis provenientes de la Cordillera Yanachaga, en los Andes del centro del Perú. Los análisis de las secuencias de ADN mitocondrial de genes ribosomales muestran que una de las especies está cercanamente relacionada con P. bipunctatus (Grupo P. conspicillatus), la segunda especie con P. stictogaster (Grupo P. peruvianus) y la tercera con varias especies del Grupo P. unistrigatus. Las primeras dos especies son morfológicamente similares a sus respectivas especies hermanas, pero sin embargo habitan en elevaciones más bajas. Se conocen 29 especies de ranas del g´nero Phrynopus y Pristimantis en las inmediaciones de la Cordillera Yanachaga. Esta diversidad de especies, particularmente de Pristimantis, es elevada en comparación con otras localidades de características similares en el Perú; sin embargo, es menor a la reportada en la vertiente occidental de los Andes del Ecuador