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Description
Science is a formalized method for acquiring information about the world. In

recent years, the ability of science to do so has been scrutinized. Attempts to reproduce

findings in diverse fields demonstrate that many results are unreliable and do not

generalize across contexts. In response to these concerns, many proposals for reform have

emerged.

Science is a formalized method for acquiring information about the world. In

recent years, the ability of science to do so has been scrutinized. Attempts to reproduce

findings in diverse fields demonstrate that many results are unreliable and do not

generalize across contexts. In response to these concerns, many proposals for reform have

emerged. Although promising, such reforms have not addressed all aspects of scientific

practice. In the social sciences, two such aspects are the diversity of study participants

and incentive structures. Most efforts to improve scientific practice focus on replicability,

but sidestep issues of generalizability. And while researchers have speculated about the

effects of incentive structures, there is little systematic study of these hypotheses. This

dissertation takes one step towards filling these gaps. Chapter 1 presents a cross-cultural

study of social discounting – the purportedly fundamental human tendency to sacrifice

more for socially-close individuals – conducted among three diverse populations (U.S.,

rural Indonesia, rural Bangladesh). This study finds no independent effect of social

distance on generosity among Indonesian and Bangladeshi participants, providing

evidence against the hypothesis that social discounting is universal. It also illustrates the

importance of studying diverse human populations for developing generalizable theories

of human nature. Chapter 2 presents a laboratory experiment with undergraduates to test

the effect of incentive structures on research accuracy, in an instantiation of the scientific

process where the key decision is how much data to collect before submitting one’s

findings. The results demonstrate that rewarding novel findings causes respondents to

make guesses with less information, thereby reducing their accuracy. Chapter 3 presents

an evolutionary agent-based model that tests the effect of competition for novel findings

on the sample size of studies that researchers conduct. This model demonstrates that

competition for novelty causes the cultural evolution of research with smaller sample

sizes and lower statistical power. However, increasing the startup costs to conducting

single studies can reduce the negative effects of competition, as can rewarding

publication of secondary findings. These combined chapters provide evidence that

aspects of current scientific practice may be detrimental to the reliability and

generalizability of research and point to potential solutions.
ContributorsTiokhin, Leonid (Author) / Hruschka, Daniel J (Thesis advisor) / Morgan, Thomas JH (Thesis advisor) / Boyd, Robert (Committee member) / Frankenhuis, Willem E. (Committee member) / Bergstrom, Carl T. (Committee member) / Arizona State University (Publisher)
Created2018
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Description
In competitive Taekwondo, Electronic Body Protectors (EBPs) are used to register hits made by players during sparring. EBPs are comprised of three main components: chest guard, foot sock, and headgear. This equipment interacts with each other through the use of magnets, electric sensors, transmitters, and a receiver. The receiver is

In competitive Taekwondo, Electronic Body Protectors (EBPs) are used to register hits made by players during sparring. EBPs are comprised of three main components: chest guard, foot sock, and headgear. This equipment interacts with each other through the use of magnets, electric sensors, transmitters, and a receiver. The receiver is connected to a computer programmed with software to process signals from the transmitter and determine whether or not a competitor scored a point. The current design of EBPs, however, have numerous shortcomings, including sensing false positives, failing to register hits, costing too much, and relying on human judgment. This thesis will thoroughly delineate the operation of the current EBPs used and discuss research performed in order to eliminate these weaknesses.
ContributorsSpell, Valerie Anne (Author) / Kozicki, Michael (Thesis director) / Kitchen, Jennifer (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
Many animals thermoregulate to maximize performance. However, interactions with other animals, such as competitors or predators, limit access to preferred microclimates. For instance, an animal may thermoregulate poorly when fighting rivals or avoiding predators. However, the distribution of thermal resources should influence how animals perceive and respond to risk. When

Many animals thermoregulate to maximize performance. However, interactions with other animals, such as competitors or predators, limit access to preferred microclimates. For instance, an animal may thermoregulate poorly when fighting rivals or avoiding predators. However, the distribution of thermal resources should influence how animals perceive and respond to risk. When thermal resources are concentrated in space, individuals compete for access, which presumably reduces the thermoregulatory performance while making their location more predictable to predators. Conversely, when thermal resources are dispersed, several individuals can thermoregulate effectively without occupying the same area. Nevertheless, interactions with competitors or predators impose a potent stress, often resulting in both behavioral and physiological changes that influence thermoregulation. To assess the costs of intraspecific competition and predation risk during thermoregulation, I measured thermoregulation, movement, and hormones of male lizards (Sceloporus jarrovi) in experiment landscapes, with clumped to patchy distributions of microclimates. I found lizards aggressively competed for access to microclimates, with larger males gaining priority access when thermal resources were aggregated. Competition reduced thermoregulatory performance, increased movements, and elevated plasma corticosterone in large and small males. However, the magnitude of these responses decreased as the patchiness of the thermal environment increased. Similarly, under simulated predation risk, lizards reduced thermoregulatory performance, decreased movements, and elevated plasma corticosterone. Again, with the magnitude of these responses decreased with increasing thermal patchiness. Interestingly, even without competitors or predators, lizards in clumped arenas moved greater distances and circulated more corticosterone than did lizards in patchy arenas, indicating the thermal quality of the thermal landscape affected the energetic demands on lizards. Thus, biologists should consider species interactions and spatial structure when modeling impacts of climate change on thermoregulation.
ContributorsRusch, Travis W (Author) / Angilletta, Michael (Thesis advisor) / Sears, Mike (Committee member) / DeNardo, Dale (Committee member) / Deviche, Pierre (Committee member) / McGraw, Kevin (Committee member) / Arizona State University (Publisher)
Created2017