Physical Sciences and Mathematics Commons^™

Spam, Fraud, And Bots: Improving The Integrity Of Online Social Media Data, Amanda Jean Minnich

Computer Science ETDs

Online data contains a wealth of information, but as with most user-generated content, it is full of noise, fraud, and automated behavior. The prevalence of "junk" and fraudulent text affects users, businesses, and researchers alike. To make matters worse, there is a lack of ground truth data for these types of text, and the appearance of the text is constantly changing as fraudsters adapt to pressures from hosting sites. The goal of my dissertation is therefore to extract high-quality content from and identify fraudulent and automated behavior in large, complex social media datasets in the absence of ground truth data. …

Search In T Cell And Robot Swarms: Balancing Extent And Intensity, George M. Fricke

Computer Science ETDs

This work investigates effective search and resource collection algorithms for swarms. Deterministic spiral algorithms and L ́evy search processes have been shown to be optimal for single searchers. We extend these strategies to swarms of robots and populations of T cells and measure performance under a variety of conditions.

Search extent and intensity lie on a continuum: more intensive patterns search thoroughly in the local area, while extensive patterns cover more area but may miss targets nearby. We show that the most efficient trade-off between search intensity and extent for swarms depends strongly on the distribution of targets, swarm size …