Support the Ex-Im Bank: It Has Work to Do!

The US Export-Import (Ex-Im) Bank is again at the center of controversy, as Congress debates the terms for its charter renewal. This policy brief critiques provisions of the House and Senate versions of the reauthorization bill and summarizes three justifications for Congress giving adequate support to the Ex-Im Bank. Box 1 provides a capsule description of the Ex-Im Bank's operations.

Steel Policy: The Good, the Bad, and the Ugly

While the US steel industry has been in distress for decades, the "steel crisis" of 1999-2001 was particularly acute. More than 30 steel producing and steel processing firms fell into bankruptcy between 1997 and 2001, and most of the failures occurred after President Bush took office. During his presidential campaign, Bush promised steelworkers that he would not neglect them. As the crisis worsened, the steel industry and the United Steel Workers of America (USWA) pressed the Bush administration to make good on its campaign promise.

Next Move in Steel: Revocation or Retaliation?

In May 2003, the World Trade Organization (WTO) dispute panel ruled that US steel safeguards imposed in March 2002 are illegal. The WTO Appellate Body is all but certain to confirm the panel's judgment, probably by December 2003. Then the Bush administration will face an important choice. It can keep the safeguards in place, pleasing steel producers and important constituencies in West Virginia, Pennsylvania, and Ohio. However, doing so would further anger steel users, who have probably lost more business and jobs as a direct consequence of the safeguards than steel producers have gained. Maintaining the safeguards would also send a signal to the world's trading nations that the United States is not prepared to endure the political cost of eliminating steel protection. Furthermore, the administration would run the risk that, in the middle of a presidential election season, foreign countries will exercise their rights under the WTO to retaliate.

Blurred Lines: Reconsidering the Roles of Teacher and Student in the Learning Process

The purpose of this study was to explore how a preservice music teacher constructed his own learning in a graduate-level independent study course with a music education faculty member as the facilitator. In this course, the student wanted to learn how to play the trumpet and improve his knowledge of jazz improvisation and style. Questions guiding this study included: How did the preservice music teacher direct his learning and construct knowledge in this course? How did the music education faculty member serve as a facilitator during this process? Data collection included journals, reflective sessions, and video recordings of classes. Data analysis involved coding with prompts from constructivist theory to assist with portraying the sequencing of teaching and learning during the semester. Findings suggest that allowing the preservice music teacher to construct his learning helped him reflect on what he had learned and plan for future teaching experiences. Recommendations include incorporating student input into coursework planning, and implementation for preservice music teachers provides opportunities for more in-depth learning of subject material. Integrating different musical styles into all coursework also helps prepare preservice music teachers for teaching a wide variety of musical styles

Efficient Bayesian Structural Equation Modeling in Stan

Structural equation models comprise a large class of popular statistical models, including factor analysis models, certain mixed models, and extensions thereof. Model estimation is complicated by the fact that we typically have multiple interdependent response variables and multiple latent variables (which may also be called random effects or hidden variables), often leading to slow and inefficient MCMC samples. In this paper, we describe and illustrate a general, efficient approach to Bayesian SEM estimation in Stan, contrasting it with previous implementations in R package blavaan (Merkle & Rosseel, 2018). After describing the approaches in detail, we conduct a practical comparison under multiple scenarios. The comparisons show that the new approach is clearly better. We also discuss ways that the approach may be extended to other models that are of interest to psychometricians.Comment: 21 pages, 5 figure

Mass fluxes and isofluxes of methane (CH4) at a New Hampshire fen measured by a continuous wave quantum cascade laser spectrometer

We have developed a mid‐infrared continuous‐wave quantum cascade laser direct‐absorption spectrometer (QCLS) capable of high frequency (≥1 Hz) measurements of 12CH4 and 13CH4 isotopologues of methane (CH4) with in situ 1‐s RMS image precision of 1.5 ‰ and Allan‐minimum precision of 0.2 ‰. We deployed this QCLS in a well‐studied New Hampshire fen to compare measurements of CH4 isoflux by eddy covariance (EC) to Keeling regressions of data from automated flux chamber sampling. Mean CH4 fluxes of 6.5 ± 0.7 mg CH4 m−2 hr−1 over two days of EC sampling in July, 2009 were indistinguishable from mean autochamber CH4 fluxes (6.6 ± 0.8 mgCH4 m−2 hr−1) over the same period. Mean image composition of emitted CH4 calculated using EC isoflux methods was −71 ± 8 ‰ (95% C.I.) while Keeling regressions of 332 chamber closing events over 8 days yielded a corresponding value of −64.5 ± 0.8 ‰. Ebullitive fluxes, representing ∼10% of total CH4 fluxes at this site, were on average 1.2 ‰ enriched in 13C compared to diffusive fluxes. CH4 isoflux time series have the potential to improve process‐based understanding of methanogenesis, fully characterize source isotopic distributions, and serve as additional constraints for both regional and global CH4 modeling analysis