In the last five years, Latin America has re-emerged on the world stage of global upstream opportunities. Brazil has proved up its massive pre-salt trend boasting tens of billions of barrels of potential. Argentina, seen as a mature producer well past its prime only a few years ago, has a new lease of life in its world-class Vaca Muerta shale province. In August, Mexico completed far-reaching energy reform; many in the industry had long hoped for this, but it had seemed politically unthinkable even after President Enrique Peña Nieto had submitted his proposal to the legislature a year earlier.
ABSTRACTAnalysis of covariance (ANCOVA) integrates analysis of variance (ANOVA) and regression. The basic advantages of ANCOVA over ANOVA are: (1) generally greater power, and (2) reduction in bias caused by differences between groups that exist before experimental treatments are administered. ANCOVA has numerous possible applications in the evaluation of simulation output, especially where the values of covariates are not known until after the simulation experiment is completed. These covariates are uncontrolled experimental variables that influence the response but are themselves unaffected by the experimental factors.This paper provides an application of multiple analysis of covariance (MANCOVA) to a simulation experiment to determine whether an intermodal transfer and blending facility should add commodity handling and storage capacity. A discrete simulation model of the plant generated cash flows from several proposed capital projects. These cash flows indicated that capacity expansion was a prudent decision. However, when the treatment means for the various combinations of additional capacity were adjusted by MANCOVA for the same levels of operating volume and scheduling performance, the adjusted cash flows produced unacceptable financial returns. In this example, the increased precision of the MANCOVA model suggested that plant management should not invest in additional storage and commodity handling capacity.
OBJECTIVE—To examine the effect of a unique organisational smoking ban on female United States Navy recruits, a population with historically high smoking rates. SETTING AND DESIGN—Study participants were female recruits (n = 5503) entering the Navy recruit training command between March 1996 and March 1997 (12 consecutive months). Participants completed smoking surveys at entry to recruit training (baseline) and again at graduation from training after exposure to an eight week, 24 hour a day smoking ban. Effects of the ban on baseline to graduation changes in perceptions of being a smoker were examined, and relapse rates among baseline ever smokers was assessed three months after leaving recruit training. RESULTS—Among all recruits, 41.4% reported being smokers at entry (that is, reported any smoking in the 30 days before entering recruit training). As a result of the ban, there was a significant reduction (from about 41% to 25%, p < 0.001) in the percentage of all women recruits who reported themselves as smokers, a much larger change than expected had no ban been in place. Relapse at the three month follow up varied according to the type of smoker at entry into the Navy, with rates ranging from 89% relapse among baseline daily smokers to 31% among baseline experimenters. CONCLUSIONS—Findings suggest that the ban provides some smokers who desire to quit with an external impetus and support to do so. However, high relapse rates indicate that more than an organisationally mandated smoking ban during recruit training is needed to help younger smokers, more regular smokers, and those who intend to continue smoking to quit after joining the Navy. Keywords: military; women; smoking ban
