Simulation of the Colombian Firm Energy Market

We present a simulation analysis of the proposed Colombian firm energy market. The main purpose of the simulation is to assess the risk to suppliers of participation in the market. We also are able to consider variations in the market design, and assess the impact of alternative auction parameters. Three simulation models are developed and analyzed. The first model (Model 1) uses historical price data from October 1995 through May 2006 to assess the performance risk of hypothetical thermal and hydro generating units. The second model (Model 2) uses historical price and operating data to assess performance risk of the actual generating units in Colombia over the same period. This analysis allows us to assess company risk. The third model (Model 3) differs from the other models in that it explicitly models the firm energy auction and investments going forward. Thus, the model is able to assess how the distribution of firm energy purchases differs from the firm energy target, and how this distribution depends on the firm energy demand curve. Model 3 also studies the investment decisions of suppliers, the impact of lumpy investments, and the impact of a higher scarcity price. Taken together, the simulation results demonstrate the risk reducing benefits of the firm energy market. Provided there is competitive new entry in response to load growth, the firm energy market should work well at coordinating investment in new supply, while minimizing supplier and consumer risks.Auctions

Geochemical and palynological signals for palaeoenvironmental change in south west England

Merged with duplicate record 10026.1/850 on 10.04.2017 by CS (TIS)This thesis evaluates the utility of a geochemical technique for the investigation of palaeoenvironmental change in south west England. The method, EDMA (Energy Dispersive X-ray Micro Analysis), is a rapid, non-destructive analysis tool, capable of detecting a large range of geochemical elements. This research examines the most appropriate method of sample preparation for organic soils and peats, and investigates the reliability of results gained from EDMA with respect to conventional bulk geochemical techniques. A detailed study focused on a range of different sedimentary sites in south west England where a variety of palaeoenvironmental changes were thought to occur. Pollen analysis was undertaken on the same sedimentary material, and provided complementary information on the nature and scale of vegetation change through time. Sediments from a coastal valley mire near North Sands, Salcombe, revealed information relating to the processes of sea-level change in this part of south Devon and the subsequent autogenic processes as the sediment accumulated through time. A range of sites were located on the granitic upland of Dartmoor. A raised bog, Tor Royal, provided data relating to the changing nature of the central upland landscape from late Mesolithic times to the present day. Two soligenous sites. Upper Merrivale and Piles Copse, sought to investigate the activities of postulated anthropogenic activity at a much smaller spatial scale, with particular interest placed upon the evidence for deforestation activity and the utilisation of the local mineral resources. The last site, Crift Down, a lowland spring fed valley mire utilised geochemical and palynological fluxes within the peat to investigate processes and activities associated with archaeological evidence for Medieval tinworking in this area of Cornwall. The results from the EDMA investigations, and comparable studies using other geochemical methods including EMMA, AAS and flame photometry, suggest the technique to have greatest applicability as a first stage tool in the analysis of general activities of past environmental change. The technique was found to yield reliable results for the major elements (Si, Al, S, Fe, Ca, K, Na and Mg), but is generally incapable of providing useful data on heavy metal elements. The data from south west England suggest the method to reflect activity at a range of different scales, and as part of a structured programme of analysis may contribute information to allow a more holistic environmental reconstruction to be made

It’s All Fun and Games until Somebody Dies: Grief, Mortality Salience, and Coping in Meaningful Permadeath

Because part of the enjoyment of video game experiences is rooted in their ability to afford players to fail but still reattempt gameplay with relatively little consequence, the appeal of playing games with permadeath seems paradoxical. This dissertation proposed that players’ motivations for playing these games with permadeath stem from an enhanced sense of appreciation garnered by players through the meaningfulness of permanent character death, rather than just through simple, hedonic enjoyment. Enhanced appreciation was expected to arise from permadeath through the grief players experienced toward the loss of their characters and through their contemplation of their own mortality. Grief was anticipated to be higher for players with stronger parasocial relationships to their characters while mortality salience was anticipated to be higher for players who identified with those game characters, and all indirect effects were expected to be moderated by players’ trait meaning making coping style. Participants (N = 394) were players recruited from various gaming subreddits on Reddit.com who had previous experiences playing permadeath games. In an online survey, they were assigned to either report on their impressions of a permadeath or a temporary character death that they had experienced in the past year. Two conditional process analyses revealed that players did report increased appreciation—through their grief for their characters—upon experiencing permadeaths, and this effect was strengthened for those attached to their characters and who were lower in trait meaning making. However, there was not parallel evidence of such an effect through mortality salience. Players’ mortality salience did increase their appreciation for playing—for players low meaning making players—but there was no indication that permadeath or identification with one’s character impacted this relationship. Theoretical implications from these findings are discussed regarding how they contribute to the literature on character attachments and uses and gratifications, as well as how games can serve as experimental playgrounds for players. A practical implication is also presented that recommends game developers work to implement PD mechanics within their own games based on the increased replayability and appreciation PD can offer to players

Avian Response to Production Stands of Native Warm-Season Grasses in the Mid-South

Grassland birds have declined more than any other guild of birds in North America, largely due to loss and degradation of native grasslands. The Conservation Reserve Program (CRP) has restored some native warm-season grasses (NWSG), but grassland birds continued to decline (-1.1% annually) partly due to the limited acreage converted (1% of southeastern US). Using NWSG in production settings provides profit incentive to landowners while reducing dependency on government programs. Studies examining these production practices and their effect on grassland birds east of the Great Plains are limited. During 2009 – 2010, I surveyed 102 NWSG fields in Kentucky and Tennessee being used for production purposes (control, biofuel, seed, hay, and pasture treatments) to assess bird use and vegetation characteristics. Landscape cover around each field (250, 500, and 1000 m) was digitized from aerial photography. Using analysis of variance (ANOVA), I compared bird (relative abundance, species diversity, and species richness) and vegetation (average height, litter depth, vertical cover, litter cover, and vegetation cover) metrics across the five treatments. Relative abundance for all species, species diversity, and species richness were all greater for seed production fields (P \u3c0.05); other treatments did not differ. Field sparrows (Spizella pusilla) were less abundant (P \u3c0.05) in biofuel than control, hay and graze treatments, whereas eastern meadowlarks (Sturnella magna) and dickcissels (Spiza americana) were more abundant in seed fields. Average vegetation height, vertical cover, percent litter, percent forbs and percent woody plants differed (P \u3c0.05) among treatments. Using Program Mark, I modeled occupancy for field sparrow, red-winged blackbird (Agelaius phoeniceus), eastern meadowlark, and northern bobwhite (Colinus virginianus) using vegetation and landscape cover as covariates. Treatment was influential in field sparrow and eastern meadowlark models, but not those for red-winged blackbird and northern bobwhite. Occupancy for field sparrow and northern bobwhite were affected by woody cover (+), for red-winged blackbird by vegetation height (-), and for eastern meadowlark by litter depth (+) or percent NWSG (+). All four species were negatively affected by forest within 250-m. Use of NWSG in production could increase the amount of available habitat and thus, help conservation efforts for grassland birds

Model Uncertainty and Policy Evaluation: Some Theory and Empirics

This paper explores ways to integrate model uncertainty into policy evaluation. We first describe a general framework for the incorporation of model uncertainty into standard econometric calculations. This framework employs Bayesian model averaging methods that have begun to appear in a range of economic studies. Second, we illustrate these general ideas in the context of assessment of simple monetary policy rules for some standard New Keynesian specifications. The specifications vary in their treatment of expectations as well as in the dynamics of output and inflation. We conclude that the Taylor rule has good robustness properties, but may reasonably be challenged in overall quality with respect to stabilization by alternative simple rules that also condition on lagged interest rates, even though these rules employ parameters that are set without accounting for model uncertainty.

Policy Evaluation in Uncertain Economic Environments

This paper develops a decision-theoretic approach to policy analysis. We argue that policy evaluation should be conducted on the basis of two factors: the policymaker's preferences, and the conditional distribution of the outcomes of interest given a policy and available information. From this perspective, the common practice of conditioning on a particular model is often inappropriate, since model uncertainty is an important element of policy evaluation. We advocate the use of model averaging to account for model uncertainty and show how it may be applied to policy evaluation exercises. We illustrate our approach with applications to monetary policy and to growth policy.

Policy Evaluation in Uncertain Economic Environments

This paper develops a general framework for economic policy evaluation. Using ideas from statistical decision theory, it argues that conventional approaches fail to appropriately integrate econometric analysis into evaluation problems. Further, it is argued that evaluation of alternative policies should explicitly account for uncertainty about the appropriate model of the economy. The paper shows how to develop an explicitly decision-theoretic approach to policy evaluation and how to incorporate model uncertainty into such an analysis. The theoretical implications of model uncertainty are explored in a set of examples, with a specific focus on how to design policies that are robust against such uncertainty. Finally, the framework is applied to the evaluation of monetary policy rules and to the analysis of tariff reductions as a way to increase aggregate economic growth.macroeconomics, Policy Evaluation, Uncertain Economic Environments

Prospectus, July 22, 1997

https://spark.parkland.edu/prospectus_1997/1017/thumbnail.jp

Prospectus, November 12, 1997

https://spark.parkland.edu/prospectus_1997/1029/thumbnail.jp

Human Pcf11 enhances degradation of RNA polymerase II-associated nascent RNA and transcriptional termination

The poly(A) (pA) signal possesses a dual function in 3′ end processing of pre-mRNA and in transcriptional termination of RNA polymerase II (Pol II) for most eukaryotic protein-coding genes. A key protein factor in yeast and Drosophila Pol II transcriptional termination is the 3′-end processing factor, Pcf11. In vitro studies suggest that Pcf11 is capable of promoting the dissociation of Pol II elongation complexes from DNA. Moreover, several mutant alleles of yeast Pcf11 effect termination in vivo. However, functions of human Pcf11 (hPcf11) in Pol II termination have not been explored. Here we show that depletion of hPcf11 from HeLa cells reduces termination efficiency. Furthermore, we provide evidence that hPcf11 is required for the efficient degradation of the 3′ product of pA site cleavage. Finally, we show that these functions of hPcf11 require an intact pA signal