75 research outputs found
The european green deal impact on the competitiveness of the agricultural sector in Portugal
This dissertation is a pedagogical case study focused on the impacts that the European Green
Deal will have at EU level in its primary sector, namely, in Portugal. A variety of concepts such
as sustainability, competitiveness and internationalization will be studied and applied to the
following hypothesis: how can the Portuguese primary sector companies, in light of the
increased cost structure, remain competitive?
The objective of this thesis is to understand, first, at a microeconomic level, the different factors
that will have an impact on the cost structure of the farmers, like the higher costs which flow
from the investments needed in new technologies. Secondly, at a macroeconomic level, an
overview over the current exports and imports and its forecast will be discussed.
It was concluded that the farmers will face some challenges and in order to ensure the success
of the European Green Deal, the latter must be addressed by different entities. There will be an
increase in costs in the short term which will need to be funded with the respective funding
options available, for instance, the CAP and the Horizon Europe. In the long term, it is of
extreme importance that the consumer’s mindset adapts to more sustainable diets. Further, so
that the internationalization of European products thrives, there needs to be a clearer regulation
so that the farmers are aware of which products they can export or import to regions which are
not in scope of these regulations.Esta tese de mestrado consiste num caso pedagógico focado nos impactos que o Pacto
Ecológico Europeu terá a nível da EU no seu setor primário, nomeadamente em Portugal.
Diversos conceitos como sustentabilidade, competitividade e internacionalização serão
estudados e aplicados à seguinte hipótese: como é que as empresas portuguesas do setor
primário, face ao aumento da estrutura de custos, podem manter-se competitivas?
O objetivo desta tese é compreender, em primeiro lugar, ao nível microeconómico, os diferentes
fatores que terão impacto na estrutura de custos dos agricultores, como os custos mais elevados
decorrentes dos investimentos necessários em novas tecnologias. Em segundo lugar, a nível
macroeconómico, será discutida uma visão geral sobre as exportações e importações atuais e a
sua previsão.
Foi concluído que os agricultores irão enfrentar alguns desafios e para garantir o sucesso do
Pacto Ecológico Europeu, este último deve ser abordado por diferentes entidades. Haverá um
aumento de custos a curto prazo que terá de ser financiado com as respetivas opções de
financiamento disponíveis, como por exemplo, a PAC e o Horizonte Europa, e a longo prazo é
de extrema importância que a mentalidade do consumidor se adapte a dietas mais sustentáveis.
Além disso, para que a internacionalização dos produtos europeus prospere, é necessária uma
regulamentação mais clara para que os agricultores saibam quais produtos podem exportar ou
importar para regiões que não estão no alcance dessas regulamentações
LaundroGraph: Self-Supervised Graph Representation Learning for Anti-Money Laundering
Anti-money laundering (AML) regulations mandate financial institutions to
deploy AML systems based on a set of rules that, when triggered, form the basis
of a suspicious alert to be assessed by human analysts. Reviewing these cases
is a cumbersome and complex task that requires analysts to navigate a large
network of financial interactions to validate suspicious movements.
Furthermore, these systems have very high false positive rates (estimated to be
over 95\%). The scarcity of labels hinders the use of alternative systems based
on supervised learning, reducing their applicability in real-world
applications.
In this work we present LaundroGraph, a novel self-supervised graph
representation learning approach to encode banking customers and financial
transactions into meaningful representations. These representations are used to
provide insights to assist the AML reviewing process, such as identifying
anomalous movements for a given customer. LaundroGraph represents the
underlying network of financial interactions as a customer-transaction
bipartite graph and trains a graph neural network on a fully self-supervised
link prediction task. We empirically demonstrate that our approach outperforms
other strong baselines on self-supervised link prediction using a real-world
dataset, improving the best non-graph baseline by p.p. of AUC. The goal is
to increase the efficiency of the reviewing process by supplying these
AI-powered insights to the analysts upon review. To the best of our knowledge,
this is the first fully self-supervised system within the context of AML
detection.Comment: Accepted at ACM International Conference on AI in Finance 2022
(ICAIF'22
FairGBM: Gradient Boosting with Fairness Constraints
Machine Learning (ML) algorithms based on gradient boosted decision trees
(GBDT) are still favored on many tabular data tasks across various mission
critical applications, from healthcare to finance. However, GBDT algorithms are
not free of the risk of bias and discriminatory decision-making. Despite GBDT's
popularity and the rapid pace of research in fair ML, existing in-processing
fair ML methods are either inapplicable to GBDT, incur in significant train
time overhead, or are inadequate for problems with high class imbalance. We
present FairGBM, a learning framework for training GBDT under fairness
constraints with little to no impact on predictive performance when compared to
unconstrained LightGBM. Since common fairness metrics are non-differentiable,
we employ a "proxy-Lagrangian" formulation using smooth convex error rate
proxies to enable gradient-based optimization. Additionally, our open-source
implementation shows an order of magnitude speedup in training time when
compared with related work, a pivotal aspect to foster the widespread adoption
of FairGBM by real-world practitioners
Promoting Fairness through Hyperparameter Optimization
Considerable research effort has been guided towards algorithmic fairness but
real-world adoption of bias reduction techniques is still scarce. Existing
methods are either metric- or model-specific, require access to sensitive
attributes at inference time, or carry high development or deployment costs.
This work explores the unfairness that emerges when optimizing ML models solely
for predictive performance, and how to mitigate it with a simple and easily
deployed intervention: fairness-aware hyperparameter optimization (HO). We
propose and evaluate fairness-aware variants of three popular HO algorithms:
Fair Random Search, Fair TPE, and Fairband. We validate our approach on a
real-world bank account opening fraud case-study, as well as on three datasets
from the fairness literature. Results show that, without extra training cost,
it is feasible to find models with 111% mean fairness increase and just 6%
decrease in performance when compared with fairness-blind HO.Comment: arXiv admin note: substantial text overlap with arXiv:2010.0366
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