Cookies
O website necessita de alguns cookies e outros recursos semelhantes para funcionar. Caso o permita, o INESC TEC irá utilizar cookies para recolher dados sobre as suas visitas, contribuindo, assim, para estatísticas agregadas que permitem melhorar o nosso serviço. Ver mais
Aceitar Rejeitar
  • Menu
Publicações

Publicações por LIAAD

2017

Personalised fading for stream data

Autores
Veloso, B; Malheiro, B; Burguillo, JC; Foss, JD;

Publicação
SAC

Abstract
This paper describes a forgetting technique for the live update of viewer profiles based on individual sliding windows, fading and incremental matrix factorization. The individual sliding window maintains, for each viewer, a queue holding the last n viewer ratings. As new viewer events occur, they are inserted in the viewer queue, by shifting and fading the queue ratings, and the viewer latent model is faded. We explored time, rating-and-position and popularity-based fading techniques, using the latter as the base fading algorithm. This approach attempts to address the problem of dynamic viewer profile updating (volatile preferences) as well as the problem of bounded processing resources (fixed size queues). The results show that our approach outperforms previous approaches, improving the quality of the predictions.

2017

Justifying CEO Pay Ratios: Analysing Corporate Responses to Bloomberg’s Listing of Standard & Poor’s 500 Pay Ratios

Autores
Branco M.C.; Delgado C.;

Publicação
CSR, Sustainability, Ethics and Governance

Abstract
This study analyzes Standard & Poor’s 500 Index top 250 companies’ responses to Bloomberg’s disclosed calculations of CEO pay ratios. The results suggest that CEO pay ratios, CEO compensations and average worker compensations do not seem to be related to the decision to respond. They also indicate that many of the corporations have adopted a strategy of avoiding the issue or deflecting attention from it by either choosing not to respond or criticizing the technicalities of the calculation of the CEO pay ratios. Corporations that responded largely conceptualize and communicate the rationale for high executive compensation in performance-driven language.

2017

Mitigating Supply Chain Risk via Sustainability Using Big Data Analytics: Evidence from the Manufacturing Supply Chain

Autores
Mani, V; Delgado, C; Hazen, BT; Patel, P;

Publicação
SUSTAINABILITY

Abstract
The use of big data analytics for forecasting business trends is gaining momentum among professionals. At the same time, supply chain risk management is important for practitioners to consider because it outlines ways through which firms can allay internal and external threats. Predicting and addressing the risks that social issues cause in the supply chain is of paramount importance to the sustainable enterprise. The aim of this research is to explore the application of big data analytics in mitigating supply chain social risk and to demonstrate how such mitigation can help in achieving environmental, economic, and social sustainability. The method involves an expert panel and survey identifying and validating social issues in the supply chain. A case study was used to illustrate the application of big data analytics in identifying and mitigating social issues in the supply chain. Our results show that companies can predict various social problems including workforce safety, fuel consumptions monitoring, workforce health, security, physical condition of vehicles, unethical behavior, theft, speeding and traffic violations through big data analytics, thereby demonstrating how information management actions can mitigate social risks. This paper contributes to the literature by integrating big data analytics with sustainability to explain how to mitigate supply chain risk.

2017

Individualizing propofol dosage: a multivariate linear model approach (vol 28, pg 525, 2014)

Autores
Rocha, C; Mendonca, T; Silva, ME; Gambus, P;

Publicação
JOURNAL OF CLINICAL MONITORING AND COMPUTING

Abstract

2017

Transthyretin (ATTR) amyloidosis nephropathy: lessons from a TTR stabilizer molecule

Autores
Rocha, A; Silva, A; Cardoso, M; Beirao, I; Alves, C; Teles, P; Coelho, T; Lobato, L;

Publicação
AMYLOID-JOURNAL OF PROTEIN FOLDING DISORDERS

Abstract

2017

The effect of temporal aggregation on the estimation accuracy of time series models

Autores
Teles, P; Sousa, PSA;

Publicação
COMMUNICATIONS IN STATISTICS-SIMULATION AND COMPUTATION

Abstract
In time series analysis, Autoregressive Moving Average (ARMA) models play a central role. Because of the importance of parameter estimation in ARMA modeling and since it is based on aggregate time series so often, we analyze the effect of temporal aggregation on estimation accuracy. We derive the relationships between the aggregate and the basic parameters and compute the actual values of the former from those of the latter in order to measure and compare their estimation accuracy. We run a simulation experiment that shows that aggregation seriously worsens estimation accuracy and that the impact increases with the order of aggregation.

  • 277
  • 516