Vol III, Issue 12  December 2007

Monte Carlo Analysis of SP-off-RP Data
NETS researchers Kenneth Train, PhD, and Wesley Wilson, PhD, have recently released a paper entitled “Monte Carlo Analysis of SP-off-RP Data.” This paper follows previous research conducted under NETS with the express purpose of estimating shipper responses. The newly presented data are a combination of revealed data (RP) and stated preference data (SP).

The revealed data reflect choices made in a real-world setting whereas stated preference data collected are constructed from revealed data (hence SP-off-RP). The stated preference data are constructed by asking the decision-maker whether he or she would choose the same alternative or switch to another alternative if the attributes of the chosen alternative were less desirable in ways specified by the researcher and/or the attributes of non-chosen alternatives were more desirable in specified ways. This construction, called "stated-preference off revealed-preference" (SP-off-RP), can increase the realism of the stated-preference task, relative to standard SP exercises, but creates endogeneity.

In this paper, Train and Wilson present a series of Monte Carlo exercises that explore SP-off-RP data using an estimator that accounts for the endogeneity. The results suggest that SP-off-RP data can provide large efficiency improvements over the use of revealed-preference data alone, especially in small samples. The results also suggest that the SP-off-RP design yields substantial efficiency gains over standard SP designs when respondents are able to answer SP-off-RP questions more accurately than standard SP questions due to their greater realism.

Fact Sheet | Paper 

Ongoing Research on Ohio River Basin Shippers
Researchers Dale Kelz and Wesley Wilson, PhD recently visited nine of the largest coal shippers in the Ohio River Basin. This effort is part of NETS ongoing research to better understand the logistics decisions of shippers, better inform the estimation of shipper response functions, and solicit firm participation and support for an ongoing survey of Ohio River Basin shippers. The survey uses multiple survey techniques (interviews, mail, telephone, and on-line) to gather information on these three aspects of shipping.

Forthcoming research will compare the various survey methods, estimate shipper response functions, and document shipping practices. Look for this research on the NETS website in 2008!

Fact Sheet

NaSS Team Meets to Discuss Progress and Future Activities
All Navigation Systems Simulation Model (NaSS) team members met at IWR December 5-7 to present their accomplishments, answer questions from other team members, and determine future activities.

Bill Woelbeling of CDM presented the current state of the BasinSym model. Michael Dean, also from CDM, presented and demonstrated the Data Analyzer-Preprocessor. Shiaaulir Wang and Ning Yang of the University of Maryland made presentations regarding their progress on the Detailed Lock Model. Cory Rogers of CDM wrapped things up by taking stock of where we are and what we need to do in the next 9 months. A Memo for Record of the meeting will be posted on the NETS site after it is finalized.

Fact Sheet | Presentations (zip, 8.0MB)

Wesley Wilson Appointed to the Board of Editors of the Review of Industrial Organization
NETS researcher Wesley Wilson was recently appointed to the Board of Editors of the Review of Industrial Organization. The journal Review of Industrial Organization is edited by Lawarence White of New York University.  It publishes research papers on all aspects of industrial organization, with a main focus on competition and monopoly.

The Review of Industrial Organization publishes papers that support its interest in research that can be verified by econometric evidence, case studies, or other real conditions. However, the Review of Industrial Organization also seeks papers that advance significant theories of industrial organization and policy.


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