Proving the performance of a new revenue management system

Revenue management (RM) is a complicated business process that can best be described ascontrol of sales (using prices, restrictions, or capacity), usually using software as a tool to aiddecisions. RM software can play a mere informative role, supplying analysts with formatted andsummarized data who use it to make control decisions (setting a price or allocating capacity fora price point), or, play a deeper role, automating the decisions process completely, at the otherextreme. The RM models and algorithms in the academic literature by and large concentrateon the latter, completely automated, level of functionality.A firm considering using a new RM model or RM system needs to evaluate its performance.Academic papers justify the performance of their models using simulations, where customerbooking requests are simulated according to some process and model, and the revenue perfor-mance of the algorithm compared to an alternate set of algorithms. Such simulations, whilean accepted part of the academic literature, and indeed providing research insight, often lackcredibility with management. Even methodologically, they are usually awed, as the simula-tions only test \within-model" performance, and say nothing as to the appropriateness of themodel in the first place. Even simulations that test against alternate models or competition arelimited by their inherent necessity on fixing some model as the universe for their testing. Theseproblems are exacerbated with RM models that attempt to model customer purchase behav-ior or competition, as the right models for competitive actions or customer purchases remainsomewhat of a mystery, or at least with no consensus on their validity.How then to validate a model? Putting it another way, we want to show that a particularmodel or algorithm is the cause of a certain improvement to the RM process compared to theexisting process. We take care to emphasize that we want to prove the said model as the causeof performance, and to compare against a (incumbent) process rather than against an alternatemodel.In this paper we describe a \live" testing experiment that we conducted at Iberia Airlineson a set of flights. A set of competing algorithms control a set of flights during adjacentweeks, and their behavior and results are observed over a relatively long period of time (9months). In parallel, a group of control flights were managed using the traditional mix of manualand algorithmic control (incumbent system). Such \sandbox" testing, while common at manylarge internet search and e-commerce companies is relatively rare in the revenue managementarea. Sandbox testing has an undisputable model of customer behavior but the experimentaldesign and analysis of results is less clear. In this paper we describe the philosophy behind theexperiment, the organizational challenges, the design and setup of the experiment, and outlinethe analysis of the results. This paper is a complement to a (more technical) related paper thatdescribes the econometrics and statistical analysis of the results.

Optimization of multiclass queueing networks with changeover times via the achievable region approach: Part I, the single-station case

We address the performance optimization problem in a single-stationmulticlass queueing network with changeover times by means of theachievable region approach. This approach seeks to obtainperformance bounds and scheduling policies from the solution of amathematical program over a relaxation of the system's performanceregion. Relaxed formulations (including linear, convex, nonconvexand positive semidefinite constraints) of this region are developedby formulating equilibrium relations satisfied by the system, withthe help of Palm calculus. Our contributions include: (1) newconstraints formulating equilibrium relations on server dynamics;(2) a flow conservation interpretation of the constraintspreviously derived by the potential function method; (3) newpositive semidefinite constraints; (4) new work decomposition lawsfor single-station multiclass queueing networks, which yield newconvex constraints; (5) a unified buffer occupancy method ofperformance analysis obtained from the constraints; (6) heuristicscheduling policies from the solution of the relaxations.

Homeland Security and Emergency Management Division Performance Plan, FY 2009

Agency Performance Plan, Homeland Security and Emergency Management Division

An enhanced concave program relaxation for choice network revenue management

The network choice revenue management problem models customers as choosing from an offer-set, andthe firm decides the best subset to offer at any given moment to maximize expected revenue. The resultingdynamic program for the firm is intractable and approximated by a deterministic linear programcalled the CDLP which has an exponential number of columns. However, under the choice-set paradigmwhen the segment consideration sets overlap, the CDLP is difficult to solve. Column generation has beenproposed but finding an entering column has been shown to be NP-hard. In this paper, starting with aconcave program formulation based on segment-level consideration sets called SDCP, we add a class ofconstraints called product constraints, that project onto subsets of intersections. In addition we proposea natural direct tightening of the SDCP called ?SDCP, and compare the performance of both methodson the benchmark data sets in the literature. Both the product constraints and the ?SDCP method arevery simple and easy to implement and are applicable to the case of overlapping segment considerationsets. In our computational testing on the benchmark data sets in the literature, SDCP with productconstraints achieves the CDLP value at a fraction of the CPU time taken by column generation and webelieve is a very promising approach for quickly approximating CDLP when segment consideration setsoverlap and the consideration sets themselves are relatively small.

Optimization of multiclass queueing networks with changeover times via the achievable region method: Part II, the multi-station case

We address the problem of scheduling a multi-station multiclassqueueing network (MQNET) with server changeover times to minimizesteady-state mean job holding costs. We present new lower boundson the best achievable cost that emerge as the values ofmathematical programming problems (linear, semidefinite, andconvex) over relaxed formulations of the system's achievableperformance region. The constraints on achievable performancedefining these formulations are obtained by formulatingsystem's equilibrium relations. Our contributions include: (1) aflow conservation interpretation and closed formulae for theconstraints previously derived by the potential function method;(2) new work decomposition laws for MQNETs; (3) new constraints(linear, convex, and semidefinite) on the performance region offirst and second moments of queue lengths for MQNETs; (4) a fastbound for a MQNET with N customer classes computed in N steps; (5)two heuristic scheduling policies: a priority-index policy, anda policy extracted from the solution of a linear programmingrelaxation.

Performance Report for Fiscal Year, 2005

I am pleased to present the performance report for the Iowa Department for the Blind for fiscal year 2005. This report is provided in compliance with sections 8E.210 and 216B.7 of the Code of Iowa. It contains valuable information about the services the Department and its partners provided for Iowans during the past fiscal year in the areas of vocational rehabilitation, library services, and resource management. Major accomplishments of the year included new food service opportunities in the Randolph-Sheppard program, extensive remodeling of the Adult Orientation and Adjustment Center, and continued national prominence in vocational rehabilitation as measured by the U.S. Rehabilitation Services Administration, which on June 13, 2005 released data on federal standards and indicators for the year ended September 30, 2004. Earnings ratios and the percentage of employment for vocational rehabilitation clients of the Department remain among the best in the nation. This is corroborated by a report released in September, 2005 by the U.S. Government Accountability Office, which tested and summarized datasets compiled by the U.S. Department of Education for the nation’s 80 vocational rehabilitation agencies. Overall, we met or exceeded 26 of 32 results targets included in this report. Key strategic challenges, developments, and trends are also discussed in the "Department Overview" that follows. Sincerely, Allen C. Harris Director, Iowa Department for the Blind

Performance Report for Fiscal Year, 2006

I am pleased to present the performance report for the Iowa Department for the Blind for fiscal year 2006. This report is provided in compliance with sections 8E.210 and 216B.7 of the Code of Iowa. It contains valuable information about the services the Department and its partners provided for Iowans during the past fiscal year in the areas of vocational rehabilitation, library services, and resource management. Major accomplishments of the year included successful administration of a federally-funded mentoring program (Pathfinders) that matches young adults ages 16-26 who are blind or visually impaired with mentors who also have vision loss, installed a state-of-the art digital recording studio in the library, and continued national prominence in vocational rehabilitation. Earnings ratios and the percentage of employment for vocational rehabilitation clients of the Department remain among the best in the nation, as measured by the U.S. Rehabilitation Services Administration, which on July 3, 2006 released data on federal standards and indicators for the year ended September 30, 2005. Overall, we met or exceeded 15 of 20 results targets included in this report. Key strategic challenges, developments, and trends are also discussed in the "Department Overview" that follows. Sincerely, Allen C. Harris Director, Iowa Department for the Blind

Performance Report for Fiscal Year, 2007

I am pleased to present the performance report for the Iowa Department for the Blind for fiscal year 2007. This report is provided in compliance with sections 8E.210 and 216B.7 of the Code of Iowa. It contains valuable information about the services the Department and its partners provided for Iowans during the past fiscal year in the areas of Vocational Rehabilitation, Independent Living, Library Services, and Resource Management. The Department determines its competitive success in a number of ways. We look at the federal standards and indicators to learn our ranking in relation to the performance of other public rehabilitation agencies. We compare our library's production and circulation figures with those from previous years to determine trends. We set our own standards for success by looking at such factors as the number of successful case closures, average hourly wage at case closure, skills training provided, and compliance with regulations. Results show that the Department is working positively toward achieving its strategic goals of increasing the independence and productivity of blind Iowans and improving access to information for blind Iowans. Major accomplishments of the year included the selection of our Library as the only agency authorized to distribute educational materials using the National Instructional Materials Accessibility Standard (NIMAS) to students in Iowa. Our Independent Living program received the Shining Star award at the Governor's Conference on Aging for its work with and outreach to older blind Iowans. The Department, the Iowa Braille School, and the Department of Education implemented new cooperative efforts to improve the coordination and delivery of services to blind and visually impaired students in Iowa. Finally, earnings ratios and the percentage of employment for vocational rehabilitation clients of the Department remain among the best in the nation, as measured by the U.S. Rehabilitation Services Administration, which on June 27, 2007 released data on federal standards and indicators for the year ended September 30, 2006. Overall, we met or exceeded 11 of 16 results targets included in this report. A discussion of the Department's services, customers, organizational structure, and budget appears in the "Department Overview" that follows. The success of the Department's programs is evident in the success achieved by blind Iowans. It is reflected in the many blind persons who can be seen traveling about independently, going to their jobs and to the community and family activities in which they participate. Sincerely, Allen C. Harris Director, Iowa Department for the Blind

Performance Report for Fiscal Year, 2008

I am pleased to present the performance report for the Iowa Department for the Blind for fiscal year 2008. This report is provided in compliance with sections 8E.210 and 216B.7 of the Code of Iowa. It contains valuable information about results achieved because of the services that we and our partners provided to blind and visually impaired Iowans during the past fiscal year in the areas of Vocational Rehabilitation, Independent Living, Library Services, and Resource Management. We determine our competitive success in a number of ways. We look at the federal standards and indicators to learn our ranking in relation to the performance of other public rehabilitation agencies. We compare our library's production and circulation figures with those from previous years to determine trends. We set our own standards for success by looking at such factors as the number of successful case closures, average hourly wage at case closure, skills training provided, and compliance with regulations. Results show that the Department is working positively toward achieving its strategic goals of increasing the independence and productivity of blind Iowans and improving access to information for blind Iowans. Major accomplishments of the year included:  The selection of our Library as one of eight libraries to receive the new digital talking book machines and books in digital media from the National Library Service for the Blind and Physically Handicapped. Priority for distribution of the machines is given to Library patrons who are veterans.  The Department, the Iowa Braille School, and the Department of Education have been promoting the new expanded core curriculum as part of their continued efforts to improve the coordination and delivery of services to blind and visually impaired students in Iowa.  The Department's five-year grant funded Pathfinders mentoring program ended this year. A total of 49 blind youths aged 16-26 were paired with successful blind adult mentors. Assessments of the program clearly showed that participation in the program had a measurable positive effect on the youth involved.  Finally, earnings ratios and the percentage of employment for vocational rehabilitation clients of the Department are among the best in the nation, as measured by the U.S. Rehabilitation Services Administration's standards and indicators for the year ended September 30, 2007. Overall, we met or exceeded 13 of 18 targets included in this report. A discussion of the Department's services, customers, and organizational structure, and budget appears in the "Department Overview" that follows. Information pertaining to performance results appears in the final section of this document. The success of the Department's programs is evident in the success achieved by blind Iowans. It is reflected in the many blind persons who can be seen traveling about independently, going to their jobs and to the community and family activities in which they participate. Sincerely, Karen A. Keninger, Director Iowa Department for the Blind

Thermal modeling and management in ultrathin chip stack technology

This paper presents a thermal modeling for power management of a new three-dimensional (3-D) thinned dies stacking process. Besides the high concentration of power dissipating sources, which is the direct consequence of the very interesting integration efficiency increase, this new ultra-compact packaging technology can suffer of the poor thermal conductivity (about 700 times smaller than silicon one) of the benzocyclobutene (BCB) used as both adhesive and planarization layers in each level of the stack. Thermal simulation was conducted using three-dimensional (3-D) FEM tool to analyze the specific behaviors in such stacked structure and to optimize the design rules. This study first describes the heat transfer limitation through the vertical path by examining particularly the case of the high dissipating sources under small area. First results of characterization in transient regime by means of dedicated test device mounted in single level structure are presented. For the design optimization, the thermal draining capabilities of a copper grid or full copper plate embedded in the intermediate layer of stacked structure are evaluated as a function of the technological parameters and the physical properties. It is shown an interest for the transverse heat extraction under the buffer devices dissipating most the power and generally localized in the peripheral zone, and for the temperature uniformization, by heat spreading mechanism, in the localized regions where the attachment of the thin die is altered. Finally, all conclusions of this analysis are used for the quantitative projections of the thermal performance of a first demonstrator based on a three-levels stacking structure for space application.

Artificial-Intelligence-Based Optimization of the Management of Snow Removal Assets and Resources Final Report, October 2002

Geographic information systems (GIS) and artificial intelligence (AI) techniques were used to develop an intelligent snow removal asset management system (SRAMS). The system has been evaluated through a case study examining snow removal from the roads in Black Hawk County, Iowa, for which the Iowa Department of Transportation (Iowa DOT) is responsible. The SRAMS is comprised of an expert system that contains the logical rules and expertise of the Iowa DOT’s snow removal experts in Black Hawk County, and a geographic information system to access and manage road data. The system is implemented on a mid-range PC by integrating MapObjects 2.1 (a GIS package), Visual Rule Studio 2.2 (an AI shell), and Visual Basic 6.0 (a programming tool). The system could efficiently be used to generate prioritized snowplowing routes in visual format, to optimize the allocation of assets for plowing, and to track materials (e.g., salt and sand). A test of the system reveals an improvement in snowplowing time by 1.9 percent for moderate snowfall and 9.7 percent for snowstorm conditions over the current manual system.

Iowa Homeland Security & Emergency Management Division Performance Report, FY2013

Agency Performance Report

Iowa Homeland Security & Emergency Management Division Performance Report, FY2014

Agency Performance Report