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1. The menu-complexity of ``one-and-a-half'' dimensional mechanism design

   Saxena, Raghuvansh R.; Schvartzman, Ariel; Weinberg, S. Matthew (January 2018, Symposium on Discrete Algorithms)

   We study the menu complexity of optimal and approximately-optimal auctions in the context of the ``FedEx'' problem, a so-called ``one-and-a-half-dimensional'' setting where a single bidder has both a value and a deadline for receiving an item [FGKK 16]. The menu complexity of an auction is equal to the number of distinct (allocation, price) pairs that a bidder might receive [HN 13]. We show the following when the bidder has $$n$$ possible deadlines: 1) Exponential menu complexity is necessary to be exactly optimal: There exist instances where the optimal mechanism has menu complexity $$\geq 2^n-1$$. This matches exactly the upper bound provided by Fiat et al.'s algorithm, and resolves one of their open questions [FGKK 16]. 2) Fully polynomial menu complexity is necessary and sufficient for approximation: For all instances, there exists a mechanism guaranteeing a multiplicative $$(1-\epsilon)$$-approximation to the optimal revenue with menu complexity $$O(n^{3/2}\sqrt{\frac{\min\{n/\epsilon,\ln(v_{\max})\}}{\epsilon}}) = O(n^2/\epsilon)$$, where $$v_{\max}$$ denotes the largest value in the support of integral distributions. \item There exist instances where any mechanism guaranteeing a multiplicative $(1-O(1/n^2))$-approximation to the optimal revenue requires menu complexity $$\Omega(n^2)$$. Our main technique is the polygon approximation of concave functions [Rote 91], and our results here should be of independent interest. We further show how our techniques can be used to resolve an open question of [DW 17] on the menu complexity of optimal auctions for a budget-constrained buyer. 

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2. Design of Risk-Sharing Mechanism Related to Extreme Events

   https://doi.org/10.3929/ethz-b-000335938  

   Tomaselli, Lorenzo; Pozzi, Matteo; Sinopoli, Bruno (April 2019, Proc. of the 19th Working Conference of the IFIP Working Group 7.5 on Reliability and Optimization of Structural Systems, ETH Zurich, Zentrum, June 26-29, 2018.)

   The occurrence of extreme events, either natural or man-made, puts stress on both the physical infrastructure, causing damages and failures, and the financial system. The following recovery process requires a large amount of resources from financial agents, such as insurance companies. If the demand for funds overpasses their capacity, these financial agents cannot fulfill their obligations, thus defaulting, without being able to deliver the requested funds. However, agents can share risk among each other, according to specific agreements. Our goal is to investigate the relationship between these agreements and the overall response of the physical/financial systems to extreme events and to identify the optimal set of agreements, according to some risk-based metrics. We model the system as a directed and weighted graph, where nodes represent financial agents and links agreements among these. Each node faces an external demand of funds coming from the physical assets, modeled as a random variable, that can be transferred to other nodes, via the directed edges. For a given probabilistic model of demands and structure of the graph, we evaluate metrics such as the expected number of defaults, and we identify the graph configuration which optimizes the metric. The identified graph suggests to the agents a set of agreements to minimize global risk. 

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3. Recognizing Engineering Students’ Funds of Knowledge: Creating and Validating Survey Measures

   Verdin, Dina; Smith, Jessica; Lucena, Juan (January 2019, Review & directory - American Society for Engineering Education)

   This research base paper examines students who are the first in their families to attend college. Our research seeks to understand the role students’ funds of knowledge makes in first-generation college students’ undergraduate experience. Funds of knowledge are the set of formal/informal knowledge and skills that students learn through family, friends, and communities outside of academic institutions. This paper reports funds of knowledge themes relevant to first-generation college students in engineering and the process of gathering validity evidence to support the funds of knowledge themes. Using ethnographic and interview data, six themes emerged: connecting experiences, community networks, tinkering knowledge, perspective taking, reading people, and mediational skills. Pilot data collected at two institutions were used to run exploratory factor analysis to verify the underlying theoretical structures among the themes. Results of the exploratory factor analysis found that almost all items reliably loaded onto their respective constructs. The funds of knowledge identified in this study are not an exhaustive account, nevertheless uncovering these hidden assets can support first-generation college students to see their experiences as equally valuable knowledge in engineering. We are currently in an ongoing process of collecting a second dataset to perform a confirmatory factor analysis, i.e., the next phase of the validation process for survey instrument development. 

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4. Stress Testing Spillover Risk in Mutual Funds

   Capponi, Agostino; Glasserman, Paul; Weber, Marko (July 2024, Management science)

   We develop a framework to quantify the vulnerability of mutual funds to fire-sale spillover losses. We account for the first-mover incentive that results from the mismatch between the liquidity offered to redeeming investors and the liquidity of assets held by the funds. In our framework, the negative feedback loop between investors' redemptions and price impact from asset sales leads to an aggregate change in funds' NAV, which is determined as a fixed point of a nonlinear mapping. We show that a higher concentration of first movers increases the aggregate vulnerability of the system, as measured by the ratio between endogenous losses due to fund redemptions and exogenous losses due to initial price shocks only. When calibrated to U.S. mutual funds, our model shows that, in stressed market scenarios, spillover losses are significantly amplified through a nonlinear response to initial shocks that results from the first-mover incentive. Higher spillover losses provide a stronger incentive to redeem early, further increasing fire-sale losses and the transmission of shocks through overlapping portfolio holdings. 

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5. Examining Engineering Migratory Students’ Funds of Knowledge: Uncovering Interpersonal Skills Needed in Engineering

   https://doi.org/10.3102/2100936  

   Trujillo_Garcia, Ulises; Verdín, Dina (April 2024, AERA)

   Interpersonal skills are essential to engineers’ work as they regularly manage large projects, engage with people, collaborate in teams, and offer vital services to society. This study explores how twelve undergraduate students from migratory/seasonal farmworker (MSFW) backgrounds use their funds of knowledge in the form of interpersonal skills in engineering. An hour-long semi-structured interview protocol was designed and used to understand the funds of knowledge participants brought into their respective engineering classrooms. Using thematic analysis, we found that MSFW students accumulated multiple interpersonal skills, such as teamwork, organizational skills, empathetic practices, work ethic, and communication. This work adds to the existing literature on funds of knowledge and puts MSFW students and their unique assets in engineering at the forefront. 

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