Remembering Leo Breiman

I published an interview of Leo Breiman in Statistical Science [Olshen (2001)], and also the solution to a problem concerning almost sure convergence of binary tree-structured estimators in regression [Olshen (2007)]. The former summarized much of my thinking about Leo up to five years before his death. I discussed the latter with Leo and dedicated that paper to his memory. Therefore, this note is on other topics. In preparing it I am reminded how much I miss this man of so many talents and interests. I miss him not because I always agreed with him, but instead because his comments about statistics in particular and life in general always elicited my substantial reflection.Comment: Published in at http://dx.doi.org/10.1214/10-AOAS385 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Remembering Leo Breiman

Leo Breiman was a highly creative, influential researcher with a down-to-earth personal style and an insistence on working on important real world problems and producing useful solutions. This paper is a short review of Breiman's extensive contributions to the field of applied statistics.Comment: Published in at http://dx.doi.org/10.1214/10-AOAS427 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

The Quaternionic Dirac Lagrangian

We discuss the use of the variational principle within quaternionic quantum mechanics. This is non-trivial because of the non commutative nature of quaternions. We derive the Dirac Lagrangian density corresponding to the two-component Dirac equation. This Lagrangian is complex projected as anticipated in previous articles and this feature is necessary even for a classical real Lagrangian.Comment: LaTex (9 pages

Remembering the Violence of Antietam

Saturday, September 8th, saw a powerful collaboration between the Civil War Institute, Antietam National Battlefield, Eastern National, and Shepherd University. Together, these organizations hosted an event titled “Remembering the Violence of Antietam” which had a morning session at Shepherd University’s Robert C. Byrd Center for Congressional History and Education. Those fortunate enough to have secured a seat in the auditorium were treated to a thought-provoking and informative string of talks. The afternoon session took place at different sites around Antietam National Battlefield. [excerpt

Reflecting on 1 October: Using Research to Inform Public Policy and Heal our Community

On October 1, 2017, Las Vegas joined a growing list of cities in the United States home to a mass shooting, including Blacksburg, Virginia; Newtown, Connecticut; San Bernardino, California; Orlando, Florida; Columbine, Colorado; Fort Hood, Texas; Parkland and Jacksonville, Florida and other locations. In the weeks following the tragedy, the nation and the Las Vegas community, including UNLV, responded with tributes to the victims, short- and long-term memorials to those killed and wounded, and calls to investigate the circumstances that led to this tragic event and to find ways to prevent future atrocities. Following the one-year anniversary of the 1 October tragedy, researchers from UNLV and the Brookings Institution continue to explore the impact of 1 October through a variety of approaches. From quantitative exploration, to qualitative analysis, and from oral histories, to social media data collection, the presentations in this community forum explore Las Vegas’s response and offer scholarly research to contribute to better public policy and understanding. Brookings Mountain West, in partnership with UNLV University Libraries, offered Reflecting on 1 October: Using Research to Inform Public Policy & Heal Our Community, a community forum featuring four research presentations, each centered on the 1 October tragedy in Las Vegas. Following the presentations, featured contributors from UNLV and the Brookings Institution responded to questions posed by the moderator

Dual-purpose self-deliverable lunar surface PV electrical power system

A safe haven and work supported PV power systems on the lunar surface will likely be required by NASA in support of the manned outpost scheduled for the post-2000 lunar/Mars exploration and colonization initiative. Initial system modeling and computer analysis shows that the concept is workable and contains no major high risk technology issues which cannot be resolved in the circa 2000 to 2025 timeframe. A specific selection of the best suited type of electric thruster has not been done; the initial modeling was done using an ion thruster, but Rocketdyne must also evaluate arc and resisto-jets before a final design can be formulated. As a general observation, it appears that such a system can deliver itself to the Moon using many system elements that must be transported as dead payload mass in more conventional delivery modes. It further appears that a larger power system providing a much higher safe haven power level is feasible if this delivery system is implemented, perhaps even sufficient to permit resource prospecting and/or lab experimentation. The concept permits growth and can be expanded to include cargo transport such as habitat and working modules. In short, the combined payload could be manned soon after landing and checkout. NASA has expended substantial resources in the development of electric propulsion concepts and hardware that can be applied to a lunar transport system such as described herein. In short, the paper may represent a viable mission on which previous investments play an invaluable role. A more comprehensive technical paper which embodies second generation analysis and system size will be prepared for near-term presentation