INFORMS Nashville – 2016
295
An Optimization Approach To Detection Of Epistatic Effects
Maryam Nikouei Mehr, Graduate Student, Iowa State University,
3004 Black Engineering, Ames, IA, 50011, United States,
mnmehr@iastate.edu, Lizhi Wang
Epistasis refers to the phenomenon where the interaction of multiple genes affects
a certain phenotype more than they do separately. Similar epistatic effects are also
ubiquitous in other application areas, where a certain effect is only observable
when a particular combination of multiple factors is present. Due to the
enormous solution space, it’s hard to detect the epistatic effect. We propose an
optimization model that attempts to detect epistatic effects where a large number
of observations are available for a relatively small number of explanatory factors.
We will share our preliminary results and discuss future research directions.
Measuring Competition Between Spanish Engineering Schools
Jordi Olivella, Universitat Politecnica de Catalunya, Avda.
Diagonal 647, Barcelona, 08860, Spain,
jorge.olivella@upc.edu,
Fernando Terres
In Spain the higher education institution choice is highly affected by the distance
between a student’s family home and the institutions. The higher education
market is, at least in part, geographically based. Measuring competition among
higher education centers needs to take also into account the specializations
offered, the number of students admitted and the tuition fees. Several measures
are proposed and tested. They are applied to the Spanish Engineering Schools.
Ambulance Dispatching Problem To Minimize Response
Time And Hospital Congestion Using Approximate
Dynamic Programming
Seonghyeon Park, Yonsei University, 29, Yonsei-ro 11-gil, 403-ho,
Seoul, 03788, Korea, Republic of,
s.park10@yonsei.ac.krAmbulance dispatching problem is to decide which ambulance to send to an
emergency call. Previous literature has mainly focused on minimizing response
time to an emergency call. However, in the environment where congestions of
each emergency room are quite different, it’s important to determine to which
hospital to transport patients to treat them efficiently. In this paper, an
approximate dynamic programming model is suggested to optimize ambulance
dispatching, minimizing response time as well as decreasing hospital congestion.
In addition, a case study based on real data is performed to demonstrate the
proposed model performs better in comparison with the existing ones.
Quantifying The Benefits Of Continuous Replenishment Program
For Partner Selection
Payam Parsa, PhD Candidate, University of Arkansas, Fayetteville,
AR, United States,
pparsa@uark.edu,
Manuel D Rossetti, Shengfan Zhang, Edward A Pohl
Supply chain collaboration programs such as Continuous Replenishment Program
(CRP) face challenges with regard to sharing the financial benefits. Supply chain
partners often suffer from the ambiguity that exists with the Return on
Investment (ROI) of the collaboration programs. This research provides a multi-
echelon supply chain model that quantifies the benefits of a continuous
replenishment program (CRP) for both partners, and at three levels of inventory
holding, transportation and ordering cost component. The model is adopted by a
major healthcare manufacturer, with thousands of products and hundreds of
demand points, in the form of a software tool.
Using An Ontology To Create Content For Clinical Assessment
Questions
Anna Perini, Innovative Knowledge Representative Specialist,
Elsevier, 1600 JFK Blvd, Philadelphia, PA, 19103, United States,
a.perini@elsevier.comUsing an ontology to create content for clinical assessment questions. This was
done by modeling patterns of existing questions and building templates to modify
existing questions using our ontological relations to create a new question.
Profile Monitoring Using Non-parametric Models For
Poisson Data
Sepehr Piri, Virginia Commonwealth University, 1015 Floyd Ave.,
PO Box 842014, Richmond, Richmond, VA, 23284, United States,
piris@vcu.eduProfile monitoring is a relatively new technique used to monitor the functional
relationship between a response variable and one or more explanatory variables
at each time period. Although many studies have been conducted in this field, in
most of them, the distribution of the response variable is assumed to be normal
which is not always appropriate. To our knowledge, few works have used profile
monitoring for poisson data. In this study, we aim to use non-parametric
approaches in profile monitoring for those situations where the appropriate
distribution is defined by the poisson.
Joint Inventory Replenishment For High Variety
Mass Customizers
Michael Prokle, PhD Candidate, University of Massachusetts-
Amherst, 290 N Pleasant Street, Apt 2, Amherst, MA, 01002,
United States,
mprokle@umass.edu, Ana Muriel
We address the joint inventory replenishment problem faced by a manufacturer
that builds unique products to customer’s specifications. Historic part usage shows
lumpy & intermittent demand. The objective is to find a joint part replenishment
policy that incorporates the status of the current order pipeline and balances
inventory, ordering, and stock-out costs, under given MOQ and lot size
requirements. In a case study of a small-size, fast-growing mass customizer, our
computational results show that a coordinated part inventory policy results in
higher customer service, virtually eliminating lost sales, while lowering cost by
taking advantage of shipping economies of scale.
Cross Price Elasticities In Retail Price Optimization
Jagdish Ramakrishnan, Walmart Labs, San Bruno, CA, United
States,
jramakrishnan@walmartlabs.com, Mátyás Sustik
In store retail, cross price effects have a significant impact on product sales.
Determining and estimating cross price elasticities for a large number of products
is a challenging problem. We use categorical information and LASSO to estimate a
sparse cross item set. We then solve a convexified price optimization problem.
Evolving Airplane Boarding Zone Plans
Ed Ramsden, Consultant, 1080 County Street, Attleboro, MA,
02703, United States,
earamsden@comcast.netTo manage the boarding process and reduce boarding times, airlines often assign
passengers into a series of ‘boarding zones’. This presentation describes a methods
of developing improved improved boarding zone assignment plans through the
use of a passenger-level boarding simulation model combined with an
evolutionary optimization algorithm.
Decision Facing Ambiguity: Mdp, Pomdp And Beyond
Mohammad Rasouli, PhD Candidate, University of Michigan,
430 South Fourth Ave, Ann Arbor, MI, 48104, United States,
rasouli@umich.eduWhile most of the decision making tools are developed for a Bayesian framework
where the decision maker knows full stochastic description of uncertainties in the
environment, decision facing ambiguity (model uncertainty and non-stochastic
uncertainty) is a better approach for modeling a lot of practical situations. We
discuss how decision making tools including MDP, POMDP, learning (e.g. Multi-
armed bandit) and team decision making can be extended for environments with
ambiguity. We discuss robustness and bounded rationality in this framework.
Optimizing Socioeconomic Balances In Schools
Rebecca Reddoch, Furman University, 3300 Poinsett Highway,
Greenville, SC, 29613, United States,
lattie.reddoch@furman.eduDoes the socioeconomic class of a student’s peers matter in the student’s ability to
learn? Several studies have suggested that it does. Despite the identification of
socioeconomic status as a correlating factor between education and achievement,
there are still large performance gaps in high schools throughout the nation.
Zoning based on distance ideally provides convenience and minimal travel costs
for students, but it is effectively zoning by neighborhood and socioeconomic
status. Here we study a multi-criteria model that assigns students to schools based
on a combination of socioeconomic and distance factors.
Sterilization Network Design
Ahmed Saif, Postdoctoral Fellow, HEC Montréal, 3000, Chemin de
la Côte-Sainte-Catherine, Montréal, QC, H3T 2A7, Canada,
ansaif1976@yahoo.comCentralizing sterilization services in hospital networks can cut cost and improve
efficiency through better utilization of resources, risk-pooling and economies-of-
scale. We compare three organization schemes: fully distributed, centralized
processing, and centralized processing and stock keeping. The sterilization
network design problem is formulated as a mixed-integer concave minimization
program, then reformulated as a mixed-integer second-order cone program with
a piecewise-linear cost function so it can be solved efficiently. Testing is done on a
realistic case study under different scenarios. The cost components in every
scheme are analyzed and managerial insights are drawn.
An Integrated Facility Location And Network Restoration Model
Under Repair Time Uncertainty
Ece Sanci, PhD Pre-Candidate Student, University of Michigan,
1205 Beal Avenue, Ann Arbor, MI, 48109, United States,
ecesanci@umich.edu,Mark Stephen Daskin
We propose a two-stage stochastic programming model for an integrated facility
location and network restoration problem in a disaster-prone region where
facility location decisions should be made in the pre-disaster stage. We capture
uncertainty in the network availability by incorporating the repair times required
to restore the damaged arcs. In contrast to other models that ignore repair times,
our model locates some facilities in remote, low-demand areas that are
unreachable for a certain number of periods following a disaster.
POSTER SESSION