Dynamic regime marginal structural mean models for estimation of optimal dynamic treatment regimes, Part II: proofs of results

In this companion article to "Dynamic Regime Marginal Structural Mean Models for Estimation of Optimal Dynamic Treatment Regimes, Part I: Main Content" [Orellana, Rotnitzky and Robins (2010), IJB, Vol. 6, Iss. 2, Art. 7] we present (i) proofs of the claims in that paper, (ii) a proposal for the computation of a confidence set for the optimal index when this lies in a finite set, and (iii) an example to aid the interpretation of the positivity assumption.

Informal settlements and placemaking : The case of Caracoli barrio in Bogotá

Placemaking in the developed world can be understood as a concept where through a social and political process, value and meaning in a particular setting is created. This focus of placemaking revolves around a setting in the urban environment, its role as a unique setting and, importantly, the people that make up this place: all of which is focused on a highly structured and formal participatory planning process.The role of placemaking in Latin America’s informal settlements, however, is largelyuntested. With more than 75% of Latin America’s population living in cities since 2001and over 30% (128 million people) of the urban population estimated to reside in what the United Nations define as slums; these informal settlements can offer alternative ways of thinking about urban space and the transformation of spaces people live in. In essence, informal settlements are, to a large extent, what people make of them through their own initiative and imagination. What they achieve is remarkable considering their limited resources and sometimes nonexistent participation in formal planning.Through empirical data collected in 2013 and 2014, this paper discusses how in theabsence of a formal participatory planning process (as the west or developed worldmay perceive it) and lack of resources the barrio of Caracoli, in Bogotá has been ableto create value and meaning in their place. This has been possible, despite social and economic difficulties –which are not to be forgotten-, through inventiveness and the richness of community members’ lives. In this sense, it can be argued that informal settlements can offer a different path to understanding the concept of placemaking currently dominating the developed world.

Marginal and Interaction Effects in Ordered Response Models

In discrete choice models the marginal effect of a variable of interest that is interacted with another variable differs from the marginal effect of a variable that is not interacted with any variable. The magnitude of the interaction effect is also not equal to the marginal effect of the interaction term. I present consistent estimators of both marginal and interaction effects in ordered response models. This procedure is general and can easily be extended to other discrete choice models.

Marginal efficiencies of long chain-polyunsaturated fatty acid use by barramundi (Lates calcarifer) when fed diets with varying blends of fish oil and poultry fat

An experiment was conducted with barramundi (Lates calcarifer) juveniles to examine the marginal efficiency of utilisation of long chain-polyunsaturated fatty acids (LC-PUFA). A series of five diets with blends of fish (anchovy) oil and poultry fat (F100:P0, F60:P40, F30:P70, F15:P85, F0:P100) were fed to 208. ±. 4.1. g fish over a 12-week period. The replacement of fish oil with poultry fat had no impact on growth performance (average final weight of 548.3. ±. 10.2. g) or feed conversion (mean = 1.14. ±. 0.02). Analysis of the whole body composition showed that the fatty acid profile reflected that of the fed diet. However it was also shown that there was a disproportional retention of some fatty acids relative to others (notably LOA, 18:2n-6 and LNA, 18:3n-3). By examining the body mass independent retention of different fatty acids with differential levels of intake of each, the marginal efficiencies of the use of these nutrients by this species were able to be determined. The differential retention of fatty acids in the meat was also examined allowing the determination of oil blending strategies to optimise meat n-3 LC-PUFA levels.