15 research outputs found
Dynamic Pricing and Inventory Management with Dual Suppliers of Different Lead Times and Disruption Risks
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109985/1/poms12221-sup-0001-OnlineSupplement.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/109985/2/poms12221.pd
Optimal Uniform Pricing Strategy of a Service Firm When Facing Two Classes of Customers
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106838/1/poms12171.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/106838/2/poms12171-sup-0001-Onlinesupplement.pd
Dynamic inventory control with limited capital and shortâterm financing
For most firms, especially the smallâ and mediumâsized ones, the operational decisions are affected by their internal capital and ability to obtain external capital. However, the majority of the literature on dynamic inventory control ignores the firm's financial status and financing issues. An important question that arises is: what are the optimal inventory and financing policies for firms with limited internal capital and limited access to external capital? In this article, we study a dynamic inventory control problem where a capitalâconstrained firm periodically purchases a product from a supplier and sells it to a market with random demands. In each period, the firm can use its own capital and/or borrow a shortâterm loan to purchase the product, with the interest rate being nondecreasing in the loan size. The objective is to maximize the firm's expected terminal wealth at the end of the planning horizon. We show that the optimal inventory policy in each period is an equityâlevelâdependent baseâstock policy, where the equity level is the sum of the firm's capital level and the value of its onâhand inventory evaluated at the purchasing cost; and the structure of the optimal policy can be characterized by four intervals of the equity level. Our results shed light on the dynamic inventory control for firms with limited capital and shortâterm financing capabilities.Copyright © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 184â201, 2014Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106828/1/nav21576.pd
The Use of Switching Point and Protection Levels to Improve Revenue Performance in OrderâDriven Production Systems
In a multiproduct orderâdriven production system, an organization has to decide how to selectively accept orders and allocate capacity to these orders so as to maximize total profit (TP). In this article, we incorporate the novel concept of switching point in developing three capacityâallocation with switching point heuristics (CASPaâc). Our analysis indicates that all three CASP heuristics outperform the firstâcomeâfirstâserved model and Barut and Sridharan's dynamic capacityâallocation process (DCAP) model. The best model,âCASPb, has an 8% and 6% average TP improvement over DCAP using the split lot and whole lot policies, respectively. In addition,âCASPbâperforms particularly well under operating conditions of tight capacity and large price differences between product classes. The introduction of a switching point, which has not been found in previous capacityâallocation heuristics, provides for a better balance between forward and backward allocation of available capacity and plays a significant role in improving TP.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/112181/1/j.1540-5915.2011.00320.x.pd
Value FULCRA: Mapping Large Language Models to the Multidimensional Spectrum of Basic Human Values
The rapid advancement of Large Language Models (LLMs) has attracted much
attention to value alignment for their responsible development. However, how to
define values in this context remains a largely unexplored question. Existing
work mainly follows the Helpful, Honest, Harmless principle and specifies
values as risk criteria formulated in the AI community, e.g., fairness and
privacy protection, suffering from poor clarity, adaptability and transparency.
Inspired by basic values in humanity and social science across cultures, this
work proposes a novel basic value alignment paradigm and introduces a value
space spanned by basic value dimensions. All LLMs' behaviors can be mapped into
the space by identifying the underlying values, possessing the potential to
address the three challenges. To foster future research, we apply the
representative Schwartz's Theory of Basic Values as an initialized example and
construct FULCRA, a dataset consisting of 5k (LLM output, value vector) pairs.
Our extensive analysis of FULCRA reveals the underlying relation between basic
values and LLMs' behaviors, demonstrating that our approach not only covers
existing mainstream risks but also anticipates possibly unidentified ones.
Additionally, we present an initial implementation of the basic value
evaluation and alignment, paving the way for future research in this line
Design of Online Auctions: Proxy versus Non-Proxy Settings
Recent years have witnessed the rapid development of online auctions. Currently, some online auctions, such as eBay, introduce a proxy bidding policy, under which bidders submit their maximum bids and delegate to a proxy agent to automatically outbid other competitors for the top bidder, whereas other online auctions do not. This paper compares these two widely used auction mechanisms (proxy setting and non-proxy setting) and characterizes the equilibrium bidding behavior and the sellerâs expected revenue. We find the proxy auction outperforms the non-proxy auction in terms of the sellerâs expected revenue. This dominance result is not prone to the specific bid announcement policy, the bidderâs knowledge regarding the number of bidders, the impact of traffic congestion along the bidding process, the number of items sold through the auction, and the existence of a reserve price. We further find that the proxy setting usually fails to sustain the truthful bidding as a dominant strategy equilibrium even if no minimum bid increments are adopted, and the possibility of a low-valuation-bidder dilemma where the low-valuation bidders could be better off if all bidders collude to bid at the last minute. We also discuss the dramatically different equilibrium bidding behaviors under the two auction mechanisms
A Note on Discrete Bid First-Price Auction with General Value Distribution
This paper evaluates the discrete bid first-price sealed-bid (FPSB) auction in a model with a general value distribution. We show that a symmetric Bayesian Nash equilibrium exists for the discrete bid FPSB auction. We further prove that the discrete bid FPSB equilibrium conditionally converges to that of a continuous bid FPSB auction
A NOTE ON DISCRETE BID FIRST-PRICE AUCTION WITH GENERAL VALUE DISTRIBUTION
This paper evaluates the discrete bid first-price sealed-bid (FPSB) auction in a model with a general value distribution. We show that a symmetric Bayesian Nash equilibrium exists for the discrete bid FPSB auction. We further prove that the discrete bid FPSB equilibrium conditionally converges to that of a continuous bid FPSB auction.First-price sealed-bid auction, discrete bid, Bayesian Nash equilibrium
Topography-guided buckling of swollen polymer bilayer films into three-dimensional structures
Thin films that exhibit spatially heterogeneous swelling often buckle into the third dimension to minimize stress. These effects, in turn, offer a promising strategy to fabricate complex three-dimensional structures from two-dimensional sheets. Here we employ surface topography as a new means to guide buckling of swollen polymer bilayer films and thereby control the morphology of resulting three-dimensional objects. Topographic patterns are created on poly(dimethylsiloxane) (PDMS) films selectively coated with a thin layer of non-swelling parylene on different sides of the patterned films. After swelling in an organic solvent, various structures are formed, including half-pipes, helical tubules, and ribbons. We demonstrate these effects and introduce a simple geometric model that qualitatively captures the relationship between surface topography and the resulting swollen film morphologies. The model's limitations are also examined.clos