Expectations of children to perform parenting tasks above their development level, a phenomenon known as parentification, is said to be destructive in western literature. However, in other cultures, children taking on some parenting duties may not be considered a detriment but rather an attribute of filial responsibility. The current study examined the relationships between identity distress and parentification as it differs by culture. A comparison of parentification by ethnicity revealed that individuals who did not classify as an ethnic minority experienced significant levels of identity distress compared to ethnic minority individuals regarding parentification. This variation may be attributed to elements of parentification seen as an expectation by some ethnic groups. Further analyses of the data and implications for understanding cultural bias in our assumptions of the adverse effects of parentification is discussed.

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This dissertation investigates the long-term performance of momentum portfolios. Its results show striking asymmetries for winners and losers and imply potentially different causes for the winner and loser components of momentum. After separately examining winners and losers relative to their respective benchmark portfolios with no momentum, we find winner momentum is smaller in magnitude, persists only for six months, and its higher return fully reverses. This is consistent with the notion that winner momentum is an overreaction to positive news and potentially destabilizing. Loser momentum is larger in magnitude, lasts for about one year, and its lower return does not reverse in the long run. This is consistent with the notion that loser momentum is an underreaction to negative news and suggests investors hold on to losers for too long. The lack of reversal for losers departs from prior studies whose findings are driven by the use of monthly rebalanced portfolio. Rebalancing cumulates an upward bias caused by noise-induced price volatility, which disproportionately affects losers more. This greater upward bias in losers creates an illusion that the winner minus loser return reverses. More appropriate approaches such as the buy-and-hold portfolio documents significantly less reversal. Existing theories that potentially conform to the overreaction of winners and underreaction of losers include overconfidence (Daniel, Hirshleifer, and Subrahmanyam, 1998), representativeness and conservatism (Barberis, Shleifer, and Vishny, 1998), interaction between agents holding asymmetric information (Hong and Stein, 1999), and investors' asymmetric response to fund performance (Vayanos and Woolley, 2013). / Doctor of Philosophy / The method employed to study a phenomenon can have an immense impact on our understanding. In the specific context of momentum - a strategy of buying stocks with good past performance and selling stocks with bad past performance, we show that the methodology choices as simple as how you form a portfolio and what you benchmark the portfolio against can produce significantly different results than previously documented. The documented pattern that momentum reverses over the long run, is confounded by the use of rebalanced portfolio and benchmarking winner and loser stocks against each other. Rebalancing embeds an upward bias into the return, with the bias increasing in the amount of noise in the price. Losers, having lower prices and smaller market values, suffer more from the upward bias. Thus, the reversal of the winner over loser return is more due to the inflated loser return from the bias than an underlying economic phenomenon. We confirm this by using a host of other portfolio formation methods that are known to mitigate the bias. With each of the other method, the loser return and the reversal are significantly reduced. We also suggest comparing winners and losers to a neutral benchmark with no momentum, rather than with each other to study the long-term pattern of momentum. This exercise turns out to be fruitful in that we find asymmetric behavior for winners and losers. Winner momentum fully reverses while loser momentum persists. The significance of the new results is that they affect our understanding of what drives momentum in the first place. The reversal of winners implies that winner momentum is an overreaction to positive news and potentially destabilizing. The persistence of losers indicates that loser momentum is an underreaction to negative news and implies investors hold on to losers for too long.

The EPA Lead and Copper Rule set Action Limits for lead and copper concentrations in potable water, but accelerated corrosion of lead in potable water systems due to a galvanic connection to copper remains a significant health risk to consumers. In addition to elevated lead release due to galvanic corrosion of lead-tin solder and leaded brass fixtures, partial lead service line replacements with copper pipe present long-term health concerns. Prior research has demonstrated that the effects of galvanic corrosion can be controlled by water chemistry, and the interplay between alkalinity, natural organic matter (NOM), and orthophosphate (added as corrosion inhibitor) may have a significant influence on corrosion of common lead plumbing materials. Results of bench-scale experiments demonstrate that in some waters galvanic corrosion can multiply lead release from lead pipe by up to 60 times, but other waters curtail the galvanic current and alleviate the effects of galvanic corrosion. Measurements of pH at the lead surface demonstrate that a corrosive micro-environment forms during stagnation in which the local pH drops to 3.0 or lower, demonstrating that the worst-case scenario for galvanic corrosion of lead occurs during long stagnation periods. In addition to water chemistry, flow pattern also has an impact on galvanic corrosion of lead. Conventional wisdom regarding lead release indicates that continuous flow results in the greatest mass of lead release, but reports of anomalously high lead concentrations after long periods of stagnation point to the contrary. In this experiment, continuous flow of chlorinated water through a Pb-Cu galvanic couple promoted Pb(IV) formation and resulted in potential reversal that caused lead pipe to become cathodic to copper and minimized lead release to water. In contrast, intermittent flow resulted in sustained galvanic attack, and a mass balance of Pb release indicated that a greater total mass of lead was released with intermittent flow. These results have important implications for assessing lead risk at the tap, especially considering long stagnation periods at facilities such as schools and increasing efforts for water conservation. Elevated copper release in potable water can cause aesthetic problems and mild health concerns and often occurs in new plumbing systems prior to the formation of a protective scale layer on the pipe surface. While solubility in new copper pipes tends to be controlled by an amorphous solid of high solubility, over time, the natural copper aging process results in the formation of a protective scale of much lower solubility, but the transition can be inhibited in waters with high levels of NOM. Experiments demonstrated that GAC treatment to remove NOM accelerates the aging process to a protective scale that provides a long-term reduction in copper release even after GAC treatment is terminated. Therefore, compared to pH adjustment and orthophosphate addition, which must be continued perpetually, GAC treatment may be a more holistically pleasing method of copper corrosion control. This approach could be useful in the commissioning of new buildings to facilitate rapid aging and avoid potential long-term copper corrosion problems. / Master of Science

This dissertation explores motivation in decision-making and action in science and technology, through the lens of a case study: scientific data sharing in cancer research. The research begins with the premise that motivation and emotion are key elements of what it means to be human, and consequently, are important variables in how individuals make decisions and take action. At the same time, institutional controls and social messaging send a variety of signals intended to motivate specific actions and behaviors. Understanding the interplay between personal motives and social influences may point to strategies that better align individual and social perceptions and discourse. To explore these dynamics, this research centers on a large-scale cancer research program led by the National Institutes of Health's National Cancer Institute. The goal of the program is to encourage interoperability and data sharing between diverse and highly autonomous cancer centers across the U.S. Housed in an organization focused on biomedical informatics, the program has a technologically-focused mission; the goal is to facilitate institutional data sharing to connect the cancer research enterprise. This focus contrasts with the more relationship-based point-to-point data sharing currently reported by researchers as the norm. Researchers are motivated to share data with others under specific conditions: when there is a foundation of trust with the person or community being shared with; when the perceived reward of sharing is well-defined and of value to the person sharing; and when there is perceived to be a lower risk or cost than the benefit received. Without these conditions, there are often determined to be insufficient incentives and rewards for sharing. Data sharing is both a personal decision and a social level problem. Data is both subjective and personal; it is often an extension of researcher's identity, and serves as a measure of his or her value and capability. In the search for standards and interoperable data sets, institutional and technologically-mediated forms of data sharing are perceived to ignore the subjective and local knowledge embodied in the data being shared. To explore these dimensions, this study considers the technology, economics, legal elements, and personal sides of data sharing, and applies two conceptual frameworks to evaluate alternatives for action. / Ph. D.

Substance-abusing individuals have been shown to perform poorer on decision-making tasks than non-substance abusing individuals (e.g. Bechara et al., 2001; Grant, Contoreggi, & London, 2000; Sanfey, Loewenstein, McClure, & Cohen, 2006). Research suggests that this difference in performance is likely due to cognitive deficits resulting from impaired functioning of the frontal lobes. Previous research suggests that two important cognitive processes regarding decision making are reversal learning (e.g. Fellows and Farah, 2005) and working memory (e.g. Hinson, Jameson, and Whitney, 2002; Jameson, Hinson, and Whitney, 2004). The purpose of the current research project was to better understand how these processes affect performance on a decision making task and to determine if a previously administered executive stressor can impact current decision making performance. One hundred thirty six individuals categorized as having either high or low working memory functioning were randomly assigned to complete one of three modified Stroop tasks (Stressor, Priming, and Control). Following completion of the modified Stroop task participants completed the Iowa Gambling Task, which is a task requiring appropriate decision making skills to complete successfully. Statistical analyses examining the quantity and frequency of cards drawn from each deck during the IGT suggested that there was no difference in performance between individuals receiving different modified Stroop tasks or high or low working memory functioning. Analyses examining the monetary outcome of performance on the IGT suggest that there may have been no differential effect between the Stressor and Priming groups, but that these active groups may have performed differently than the Control group. Within the Low working memory block, participants in these active groups may have performed worse than Control group participants, but within the High working memory block participants in these active groups may have performed better than Control group participants. These findings are discussed with regards to previous similar investigations as well as within the broader literature of decision making. Limitations of the current study as well as implications for future investigations are also discussed. / Ph. D.

No / We examine short- and the long-term price effect associated with the FTSE 100 index revisions. We control for both heteroskedastic nature of the residual and the change, between the estimation and the test period, in the beta coefficient of the standard market model. Our findings reveal no relationship between the long-term price reversals and the change in the discount rate, as approximated by the beta coefficient of the market model. Overall, we provide strong evidence in favour of the price pressure hypothesis, where the price increase (decrease) gradually starting before the announcement an inclusion (exclusion) and reverses completely in less than two weeks after the index revision date.