Has the DRG System Influenced the Efficiency of Diagnostic Technology in Portugal?

The use of Diagnostic Related Groups (DRG) as a mechanism for hospital financing is a currently debated topic in Portugal. The DRG system was scheduled to be initiated by the Health Ministry of Portugal on January 1, 1990 as an instrument for the allocation of public hospital budgets funded by the National Health Service (NHS), and as a method of payment for other third party payers (ex. Public Employees (ADSE), private insurers, etc.). Based on experience from other countries such as the United States, it was expected that implementation of this system would result in more efficient hospital resource utilisation and a more equitable distribution of hospital budgets. However, in order to minimise the potentially adverse financial impact on hospitals, the Portuguese Health Ministry decided to gradually phase in the use of the DRG system for budget allocation by using blended hospital-specific and national DRG case-mix rates. Since implementation in 1990, the percentage of each hospital's budget based on hospital specific costs was to decrease, while the percentage based on DRG case-mix was to increase. This was scheduled to continue until 1995 when the plan called for allocating yearly budgets on a 50% national and 50% hospital-specific cost basis. While all other non- NHS third party payers are currently paying based on DRGs, the adoption of DRG case-mix as a National Health Service budget setting tool has been slower than anticipated. There is now some argument in both the political and academic communities as to the appropriateness of DRGs as a budget setting criterion as well as to their impact on hospital efficiency in Portugal. This paper uses a two-stage procedure to assess the impact of actual DRG payment on the productivity (through its components, i.e. technological change and technical efficiency change) of diagnostic technology in Portuguese hospitals during the years 1992-1994, using both parametric and non-parametric frontier models. We find evidence that the DRG payment system does appear to have had a positive impact on productivity and technical efficiency of some commonly employed diagnostic technologies in Portugal during this time span.

On understanding character-level models for representing morphology

Morphology is the study of how words are composed of smaller units of meaning (morphemes). It allows humans to create, memorize, and understand words in their language. To process and understand human languages, we expect our computational models to also learn morphology. Recent advances in neural network models provide us with models that compose word representations from smaller units like word segments, character n-grams, or characters. These so-called subword unit models do not explicitly model morphology yet they achieve impressive performance across many multilingual NLP tasks, especially on languages with complex morphological processes. This thesis aims to shed light on the following questions: (1) What do subword unit models learn about morphology? (2) Do we still need prior knowledge about morphology? (3) How do subword unit models interact with morphological typology? First, we systematically compare various subword unit models and study their performance across language typologies. We show that models based on characters are particularly effective because they learn orthographic regularities which are consistent with morphology. To understand which aspects of morphology are not captured by these models, we compare them with an oracle with access to explicit morphological analysis. We show that in the case of dependency parsing, character-level models are still poor in representing words with ambiguous analyses. We then demonstrate how explicit modeling of morphology is helpful in such cases. Finally, we study how character-level models perform in low resource, cross-lingual NLP scenarios, whether they can facilitate cross-linguistic transfer of morphology across related languages. While we show that cross-lingual character-level models can improve low-resource NLP performance, our analysis suggests that it is mostly because of the structural similarities between languages and we do not yet find any strong evidence of crosslinguistic transfer of morphology. This thesis presents a careful, in-depth study and analyses of character-level models and their relation to morphology, providing insights and future research directions on building morphologically-aware computational NLP models

From characters to words to in between: Do we capture morphology?

Words can be represented by composing the representations of subword units such as word segments, characters, and/or character n-grams. While such representations are effective and may capture the morphological regularities of words, they have not been systematically compared, and it is not understood how they interact with different morphological typologies. On a language modeling task, we present experiments that systematically vary (1) the basic unit of representation, (2) the composition of these representations, and (3) the morphological typology of the language modeled. Our results extend previous findings that character representations are effective across typologies, and we find that a previously unstudied combination of character trigram representations composed with bi-LSTMs outperforms most others. But we also find room for improvement: none of the character-level models match the predictive accuracy of a model with access to true morphological analyses, even when learned from an order of magnitude more data.Comment: Accepted at ACL 201

What do character-level models learn about morphology? The case of dependency parsing

When parsing morphologically-rich languages with neural models, it is beneficial to model input at the character level, and it has been claimed that this is because character-level models learn morphology. We test these claims by comparing character-level models to an oracle with access to explicit morphological analysis on twelve languages with varying morphological typologies. Our results highlight many strengths of character-level models, but also show that they are poor at disambiguating some words, particularly in the face of case syncretism. We then demonstrate that explicitly modeling morphological case improves our best model, showing that character-level models can benefit from targeted forms of explicit morphological modeling.Comment: EMNLP 201

Dinâmicas migratórias, trabalho e diferenciação social: o caso das migrações em Caxias do Sul

The purpose of this study is to discuss the recent migration dynamics taking place in a medium-sized city in southern Brazil. Such town has been marked by different migration flows since its initial occupation, and these flows have been changing in accordance with different national circumstances. The flows of migration to Caxias do Sul are driven by labor, which makes the work category the focus of this study. The work category is analyzed  as an element of social differentiation that contributes to the understanding of  identification processes. The study is of exploratory and qualitative nature. The results show that the distinct flows of migration that arrived in the city highlight identification issues according to its  society of origin. They also show that the different populations who moved to Caxias do Sul were motivated by the search for work, having internal migration stimulated the design of social mobility and international guarantees for work.El propósito de este estudio es discutir las dinámicas migratorias recientes ocurridas en una ciudad de mediano porte del sur de Brasil. Esa ciudad fue marcada por diferentes flujos migratorios desde su ocupación inicial, y esos flujos se fueron modificando a partir de diferentes coyunturas nacionales. Los flujos migratorios para Caxias do Sul son de tipo laboral, lo que hace con que la categoría trabajo sea el foco de este estudio. La categoría trabajo es analizada como un elemento de diferenciación social que colabora para el entendimiento de los procesos identitarios. El estudio es de naturaleza exploratoria y de cuño cualitativo. Los resultados muestran que los distintos flujos que llegaron a la ciudad acentúan las cuestiones identitarias, dependiendo de la sociedad de origen del flujo. Muestran, también, que los diversos desplazamientos poblacionales que se dirigieron a Caxias do Sul fueron motivados por la búsqueda de trabajo, siendo que las migraciones internas fueron estimuladas por la concepción de ascenso social y  las internacionales, por garantía de trabajo.Le but de cette étude est celui de discuter les dynamiques migratoires récentes survenues dans une ville de taille moyenne du sud du Brésil. Cette ville a été marquée par différents flux migratoires depuis son occupation initiale, et ces flux ont été modifiés à partir de différentes conjonctions nationales. Les flux migratoires vers Caxias do Sul sont de nature ouvrière, ce qui fait que la catégorie travail soit au centre de cette étude. La catégorie travail est analysée comme un élément de différenciation sociale qui contribue à la compréhension des processus identitaires. L’étude est de nature exploratoire et de nature qualitative. Les résultats montrent que les différents flux qui arrivent dans la ville accentuent les problèmes d’identité, en fonction de la société d’origine du flux. Ils montrent également que les différents déplacements de population vers Caxias do Sul ont été motivés par la recherche de travail, étant que les migrations internes ont été stimulés par la conception de la promotion sociale, tandis que les migrations internationales l’ont été par la garantie d’avoir un travail.Le but de cette étude est celui de discuter les dynamiques migratoires récentes survenues dans une ville de taille moyenne du sud du Brésil. Cette ville a été marquée par différents flux migratoires depuis son occupation initiale, et ces flux ont été modifiés à partir de différentes conjonctions nationales. Les flux migratoires vers Caxias do Sul sont de nature ouvrière, ce qui fait que la catégorie travail soit au centre de cette étude. La catégorie travail est analysée comme un élément de différenciation sociale qui contribue à la compréhension des processus identitaires. L'étude est de nature exploratoire et de nature qualitative. Les résultats montrent que les différents flux qui arrivent dans la ville accentuent les problèmes d’identité, en fonction de la société d’origine du flux. Ils montrent également que les différents déplacements de population vers Caxias do Sul ont été motivés par la recherche de travail, étant que les migrations internes ont été stimulés par la conception de la promotion sociale, tandis que les migrations internationales l’ont été par la garantie d’avoir un travail.O propósito deste estudo é discutir as dinâmicas migratórias recentes ocorridas em uma cidade de porte médio do sul do Brasil. Essa cidadefoi marcada por diferentes fluxos migratórios desde a sua ocupação inicial, e esses fluxos foram se modificando a partir de diferentes conjunturas nacionais. Os fluxos migratórios para Caxias do Sul são de tipo laboral, o que faz com que a categoria trabalho seja o foco do estudo. A categoria trabalho é analisada como um elemento de diferenciação social que colabora para o entendimento dos processos identitários. O estudo é de natureza exploratória e de cunho qualitativo. Os resultados mostram que os distintos fluxos que chegaram à cidade acentuam as questões identitárias, dependendo da sociedade de origem do fluxo. Mostram também que os diversos deslocamentos populacionais que se direcionaram à Caxias do Sul foram motivados pela busca por trabalho, sendo as migrações internas estimuladas pela concepção de ascensão social, e as internacionais por garantias de trabalho