Foraging under conditions of short-term exploitative competition: The case of stock traders

Theory purports that animal foraging choices evolve to maximize returns, such as net energy intake. Empirical research in both human and nonhuman animals reveals that individuals often attend to the foraging choices of their competitors while making their own foraging choices. Due to the complications of gathering field data or constructing experiments, however, broad facts relating theoretically optimal and empirically realized foraging choices are only now emerging. Here, we analyze foraging choices of a cohort of professional day traders who must choose between trading the same stock multiple times in a row---patch exploitation---or switching to a different stock---patch exploration---with potentially higher returns. We measure the difference between a trader's resource intake and the competitors' expected intake within a short period of time---a difference we call short-term comparative returns. We find that traders' choices can be explained by foraging heuristics that maximize their daily short-term comparative returns. However, we find no one-best relationship between different trading choices and net income intake. This suggests that traders' choices can be short-term win oriented and, paradoxically, maybe maladaptive for absolute market returns

Speeding up Stochastic Dynamic Programming with Zero-Delay Convolution

We show how a technique from signal processing known as zero-delay convolution can be used to develop more efficient dynamic programming algorithms for a broad class of stochastic optimization problems. This class includes several variants of discrete stochastic shortest path, scheduling, and knapsack problems, all of which involve making a series of decisions over time that have stochastic consequences in terms of the temporal delay between successive decisions. We also correct a flaw in the original analysis of the zero-delay convolution algorithm

Composing in words and images : a proposal for a tandem approach to written and visual composition pedagogy

This project proposes a module for teaching visual composition within the context of a written composition course. Drawing from process writing theory, critical pedagogy, and photo-elicitation, “Composing In Words And Images” gives composition teachers a module and direct instruction for the incorporation of critical visual composition studies in their writing classes

Identity theft and routine activities : a test of victimization using college students.

This thesis examines the link between routine activity theory and identity theft victimization using college students. Using data collected from 308 undergraduate students attending a southeastern university, this study seeks to present the likelihood that college students will become a victim to identity theft in the future. In doing so, the study also seeks to present the college student\u27s perception that they could become a victim of identity theft in the future. Overall, this study has the main objective of determining if a link exists between college student\u27s routine activities and the risk of them becoming victims of identity theft. The results specifically showed that how college students guard their credit card information (i.e., receipts) directly affects their likelihood of identity theft victimization. Additionally, support was found for two elements of routine activity theory, suggesting routine activity theory is important to the study of the identity theft victimization. Policy implications for these findings are discussed

Low Density Lipoprotein Receptor-Related Protein and Apolipoprotein E Expression is Altered in Schizophrenia

Our recent microarray study reported altered mRNA expression of several low density lipoprotein receptor-related proteins (LRP) associated with the first 4 years following diagnosis with schizophrenia. Whilst this finding is novel, apolipoprotein E (APOE), which mediates its activity through LRPs, has been reported by several studies to be altered in brains of subjects with schizophrenia. We used qPCR to measure the expression of LRP2, LRP4, LRP6, LRP8, LRP10 and LRP12 mRNA in Brodmann's area (BA) 46 of the dorsolateral prefrontal cortex in 15 subjects with short duration of illness schizophrenia (SDS) and 15 pair matched controls. We also used Western blotting to measure APOE protein expression in BA46 from these subjects. Amongst the LRPs examined, LRP10 expression was significantly increased (P = 0.03) and LRP12 was significantly decreased (P < 0.01) in SDS. APOE protein expression was also increased in SDS (P = 0.01). No other marker examined in this study was altered with diagnosis. Our data supports a role for distinct members of the LRP family in the pathology of schizophrenia and adds weight to the hypothesis that aberrant apolipoprotein signaling is involved in the early stages of schizophrenia