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We study optimal pricing in a single server queue when the customers valuation of service depends on their waiting time. In particular, we consider a very general model, where the customer valuations are random and are sampled from a distribution that depends on the queue length. The goal of the service provider is to set dynamic state dependent prices in order to maximize its revenue, while also managing congestion. We model the problem as a Markov decision process and present structural results on the optimal policy. We also present an algorithm to find an approximate optimal policy. We further present a myopic policy that is easy to evaluate and present bounds on its performance. We finally illustrate the quality of our approximate solution and the myopic solution using numerical simulations.
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A Road Map for Planning Course Transformation Using Learning Objectives
In this essay, we present a roadmap to help faculty who wish to learn how to use LOs to transform courses. We highlight the challenges faced when planning and undergoing a course transformation and present the lessons learned and common roadblocks that are reported in the literature.
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- Award ID(s):
- 2012362
- PAR ID:
- 10583075
- Editor(s):
- Gardner, Stephanie
- Publisher / Repository:
- American Society for Cell Biology
- Date Published:
- Journal Name:
- CBE—Life Sciences Education
- Volume:
- 23
- Issue:
- 2
- ISSN:
- 1931-7913
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract ObjectivesSince 2010, genome‐wide data from hundreds of ancient Native Americans have contributed to the understanding of Americas' prehistory. However, these samples have never been studied as a single dataset, and distinct relationships among themselves and with present‐day populations may have never come to light. Here, we reassess genomic diversity and population structure of 223 ancient Native Americans published between 2010 and 2019. Materials and MethodsThe genomic data from ancient Americas was merged with a worldwide reference panel of 278 present‐day genomes from the Simons Genome Diversity Project and then analyzed through ADMIXTURE,D‐statistics, PCA, t‐SNE, and UMAP. ResultsWe find largely similar population structures in ancient and present‐day Americas. However, the population structure of contemporary Native Americans, traced here to at least 10,000 years before present, is noticeably less diverse than their ancient counterparts, a possible outcome of the European contact. Additionally, in the past there were greater levels of population structure in North than in South America, except for ancient Brazil, which harbors comparatively high degrees of structure. Moreover, we find a component of genetic ancestry in the ancient dataset that is closely related to that of present‐day Oceanic populations but does not correspond to the previously reported Australasian signal. Lastly, we report an expansion of the Ancient Beringian ancestry, previously reported for only one sample. DiscussionOverall, our findings support a complex scenario for the settlement of the Americas, accommodating the occurrence of founder effects and the emergence of ancestral mixing events at the regional level.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1187/cbe.23-06-0114
