The University of Minnesota, Morris Undergraduate Research Symposium offers undergraduates the opportunity to present their research, creative work, or art performances to their peers, faculty, and the campus community. For more information, see the Undergraduate Research Symposium website. The 2024 Undergraduate Research Symposium was held on April 17, 2024.
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The Relationship Between Fatalities in Police Violence and Their Identifying Characteristics: Age, Gender, Race, and Region
Yuechu Hu
Police violence, highlighted by the George Floyd incident in 2020, has intensified concerns about police brutality and perceived racism in U.S. law enforcement (AP News, 2022). Therefore, we intend to analyze Fatal Encounters data, which documents non-police deaths that occur in the presence of the police in the United States. By creating statistical tables and graphs, as well as applying time-series methods, classification and regression trees, and a multinomial logistic regression model, we find that males and transgender people are more likely than females to encounter victimization during police brutality enforcement for any cause of death. Victims older than 19 are more likely to die in police brutality enforcement than victims younger than 19.
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Enhancing Evolutionary Computation: Optimizing Phylogeny-Informed Fitness Estimation Through Strategic Modifications
Chenfei Peng and Nic McPhee
In evolutionary computation, programs are developed using evolution's basic principles, such as selection, mutation, and recombination, to iteratively improve problem solutions towards optimal outcomes in a reasonable amount of time. To save time and be more efficient, we are currently exploring a modified version of phylogeny-informed fitness estimation. The original version evaluates each individual program on a subset of the training cases and estimates the performance everywhere else according to its parent's performance. Our approach involves comprehensive evaluation of promising programs across all training cases, increasing computational investment where the sub-sampled results indicated potential gains. This method led to our modified algorithms finding solutions in fewer generations, but at the cost of increased computation time. One question is how to determine whether a solution is promising enough to warrant this additional evaluation. To address this, we used a threshold-k, requiring that a child should be better than its parent in at least k training cases. Analysis of 30 trials on a simple test problem showed threshold-3 enhanced time efficiency, while threshold-1 minimized the number of generations needed for success. A further 100-run analysis with much lower generation limits revealed that threshold-1 secured the highest success rates. To sum up, we did a lot of interesting experiments using a modified version of phylogeny-informed fitness estimation, including comparisons between modified version and original one, 30 runs and 100 runs, complex regression problem and fuel-cost problem.
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Effect of Assay Medium pH on Inhibitory Ability of Streptomyces
Trevor Swan and Miriam Gieske
Streptomyces bacteria from soil often produce antibiotics which inhibit growth of other microbes. When comparing Streptomyces’ inhibitory ability between different soils, it may be important to match the pH of the medium used in assays to the pH of the soil they came from. We assayed Streptomyces isolates collected from a long-term agricultural experiment with nitrogen-fertilized and non-fertilized treatments to determine their ability to inhibit growth of other bacteria by producing antibiotics. Average soil pH was 6.8 in fertilized soil and 7.2 in non-fertilized soil. We dotted isolates on a glucose-asparagine agar medium adjusted to different pH values and overlaid them with a non-pathogenic Streptomyces standard to measure their inhibitory ability. Some isolates produced different inhibition zone sizes depending on medium pH. However, response to assay medium pH did not differ significantly among isolates from soils of different pH. More tests are needed to determine whether it is necessary to match the medium pH to the pH of the soil the isolates came from when comparing prevalence of antibiotic production among Streptomyces from different soils
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Providing Beginners with Interactive Exploration of Error Messages in Clojure
John Walbran and Elena Machkasova
Programmers are imperfect, and will often make mistakes when programming and create a program error, for example, attempting to divide by zero. When a computer tries to run a program with an error, the program will halt and present the details of the error to the user in the form of an error message. These error messages are often very jargon-heavy, and are not designed to be palatable to a novice programmer. This creates significant friction for new programmers trying to learn programming languages. This work is a part of an ongoing project (called Babel) led by Elena Machkasova in an attempt to ease this friction in the Clojure programming language. Currently, Babel software is able to replace standard error messages with ones that are more helpful for a beginner audience. My contribution to this project is an exploration of potential tools to effectively display information about errors in an interactive and intuitive manner. The most promising of these tools up to this point has been Morse, created by the company Cognitect, owned by Nubank. As this project continues to explore the possibilities of Morse and how it can integrate with the existing Babel system, we are putting together potential setups that novice programmers can use to effectively understand and explore the causes of the errors they come across. This project presents the setups that have been developed and discuss their benefits and tradeoffs in helping novice programmers understand error messages.