Percorrer por autor "Vaz, Clara B."
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- A afiliação a uma marca: retrato dos estabelecimentos hoteleiros em PortugalPublication . Alves, Jorge; Vaz, Clara B.; Martins, Catarina AntóniaA hotelaria é um dos setores mais importantes na atividade turística em Portugal. Conhecer as características e especificidades das unidades hoteleiras a operar em Portugal é importante para todos aqueles que tomam decisões sobre o investimento neste setor. Conhecer a realidade da afiliação dos estabelecimentos hoteleiros portugueses a uma marca é também uma questão de muito interesse para os hoteleiros no apoio à tomada de decisões estratégicas. Com recurso à análise do universo dos estabelecimentos hoteleiros existentes em Portugal, é feita a sua caracterização quanto às especificidades, instalações e equipamentos. Em termos metodológicos estima-se um modelo de regressão logística que permite discutir a afiliação dos estabelecimentos hoteleiros portugueses a uma marca. Os resultados permitem concluir que pouco mais de um terço dos estabelecimentos hoteleiros em Portugal são afiliados a uma marca, sendo esta afiliação mais frequente nas regiões mais turísticas. Os resultados permitem ainda verificar que os estabelecimentos hoteleiros afiliados possuem, em média, maior número de estrelas, maior capacidade e menor número de equipamentos que os estabelecimentos hoteleiros não afiliados.
- An application of DEA to the third sector: the case of children and youth householdsPublication . Vaz, Clara B.; Mendes, Ivo; Alves, JorgeThe Portuguese state has transferred some areas of its social program for third sector entities, including private social welfare institutions. This transfer of powers is supported by providing economic subsidies, being public entities responsible to monitor the efficient management by those institutions. This research aims to present a contribution to monitor the efficient management of resources by the institutions that look after children and young people. The DEA method is used to assess the technical efficiency of eight institutions from Bragança district, during the years 2010 to 2013. This model evaluates each institution in reduction of resource levels used to provide social services to the level of users observed in each unit. This approach should be used to complement the assessment of quality in providing social services, which is currently performed by the regulator, in order to allow monitoring the overall performance of such institutions.
- Análise da evolução da produtividade de lojas de retalho utilizando o índice de MalmquistPublication . Vaz, Clara B.; Camanho, AnaEste artigo pretende avaliar a evolução da produtividade ao longo do tempo de lojas de retalho de base alimentar (hipermercados e supermercados), utilizando o índice de Malmquist. Na avaliação da evolução da produtividade há que ter em conta dois efeitos: a alteração da eficiência técnica de cada loja e a alteração da fronteira da tecnologia. O índice de Malmquist permite captar correctamente estes dois efeitos. A alteração da eficiência técnica permite verificar se a loja se está a aproximar dos níveis de desempenho observados nas melhores lojas. A alteração da fronteira da tecnologia traduz a mudança tecnológica verificada no processo de produção entre dois períodos, resultante, por exemplo, da introdução de um novo equipamento nas lojas (e.g. caixas mais rápidas), de alterações no modelo de gestão central das lojas, ou de alterações no contexto que caracteriza o sector do retalho. As contribuições principais deste artigo relacionam-se com a análise do percurso das lojas entre dois períodos, de forma a identificar lojas inovadoras, e com a análise da significância estatística das alterações de produtividade detectadas na cadeia de lojas. Este artigo propõe o uso de testes não-paramétricos para analisar se as diferenças detectadas entre os dois períodos ao nível das várias componentes do índice de Malmquist são estatisticamente significativas. Os métodos desenvolvidos são aplicados a um caso real de uma cadeia de supermercados e hipermercados Portugueses para avaliar a evolução da produtividade entre os anos 2002 e 2004.
- Analysis of the effect of environmental conditions on the performance of retailing storesPublication . Vaz, Clara B.; Camanho, AnaThe assessment of performance in retailing services has gained considerable attention in recent years. The increased competition motivated the organisations to strive for efficiency in order to cut costs and deliver better customer services. This paper develops a method based on Data Envelopment Analysis (DEA) for the efficiency assessment of retailing stores. The method enables the quantification of inefficiencies taking into account the effect of exogenously factors (i.e., non-discretionary inputs and outputs). The method developed starts with the identification of the factors that affect the DMUs’ performance, including those outside the decision makers’ control. The statistical significance of the effect of the exogenous factors on performance is tested using the Kolmogorov-Smirnov test, such that only the relevant factors are considered in the DEA assessment. An enhanced DEA model is run for each store, ensuring that the definition of the efficient frontier is based exclusively on the discretionary variables, and only comparable stores are allowed as peers, i.e., stores whose area of influence is identical or less favourable than the catchment area of the store under assessment. As a result, the shape of the production possibility set is adjusted for each DMU according to the exogenous conditions where it operates. To avoid the loss of discrimination power of the DEA analysis, the choice of the peers authorized in the assessments is done allowing for trade-offs between the nondiscretionary factors (e.g., a store with more population in the surrounding area than the DMU under assessment may be allowed as peer if its level of competition is also higher). The adjustments required to the standard DEA model imply the definition of a mixed integer DEA formulation. To disentangle technical inefficiency from the effect of environmental conditions, the results of the DEA model that takes into account the environmental conditions are compared with the results of a standard DEA model including only the discretionary inputs and outputs. This analysis showed that the average efficiency estimates of the stores analysed increases when the exogenous factors are taken into account, with the efficiency values for some stores increasing up to 15%. Finally, to explore in more detail the impact of each of the non-discretionary factors (population and competition) on the performance of individual stores, a “step by step” approach was used. This approach consists of adding to the DEA model the environmental factors, one at each time (like a stepwise procedure of regression analysis). The results obtained in the successive models are analysed for each DMU to quantify the effect of each exogenous variable on store performance. The applicability of the approach developed in this paper is illustrated in the context of a real-world efficiency assessment of grocery stores. The assessment adopted an output oriented perspective, consistent with the objective of sales maximization. The managerial implications of the results obtained are explored, comparing the insights gained with the DEA analysis with the results of the approaches for managerial planning and control currently used in the organisation.
- Application of Benford’s law to detect signs of under-invoicing in companies in the restaurant sector during the COVID-19 pandemicPublication . Martins, Ana Catarina Rodrigues; Alves, Jorge; Vaz, Clara B.The main objective of this study is to detect signs of under-invoicing by applying Benford‘s law to the Portuguese restaurant sector during the COVID-19 pandemic, in the context of government support policies. Between 2020 and 2021, the State adopted several measures to provide additional support to companies that have seen a significant decrease in their activity, namely, a reduction of at least 25% in turnover. A literature review was carried out focusing on the impact of the COVID-19 pandemic on the companies under analysis, the support measures adopted by the State and, finally, a survey of the theoretical component relating to the application of Benford‘s law in accounting. The data were collected from the Iberian Balance Sheet Analysis System database for 2019, 2020, and 2021. After analysing the data, significant deviations are observed in several digits, practically for all the compliance tests, both in the analysis of the first digit test and in the analysis of the first two digits test. The results therefore show signs of under-invoicing in 2020 by the analysed companies, which suffered, on average, a 79% reduction in turnover.
- Assessing group performance with Malmquist indices: the evaluation of the brand effect in retailingPublication . Camanho, Ana; Vaz, Clara B.This study explores the differences in performance between two groups of grocery stores with different brands. The paper develops a Malmquist-type index to distinguish internal inefficiencies from those associated with the group (or brand) characteristics. A fundamental characteristic of the new index is to compare in a static setting.
- Assessing the brand effect on the efficiency of retailing storesPublication . Vaz, Clara B.; Camanho, AnaThis paper explores the differences in performance between two groups of grocery stores that operate with different brands. The study develops a Malmquist-type index to distinguish internal inefficiencies from those associated with the group (or brand) characteristics. A fundamental characteristic of the new index is to compare groups in a static setting. The study described in this paper combines the use of a Malmquist-type index with statistical testes. The Malmquist-type index is decomposed into sub-indexes for comparing the efficiency spread between groups and the productivity differences between the best-practice frontiers of the groups. The hypothesis tests are used to verify if the differences between groups captured by the Malmquist-type index and its components are statistically significant. There are several methods based on DEA for comparing the performance of two groups, such as the program efficiency method, the comparison of efficiency distributions using statistical hypothesis tests, and methods based on the Malmquist index. The strengths and weaknesses of these methods are explored using data sets that represent different scenarios regarding the relative position of the frontiers and the efficiency spread within the groups. The new method used in this paper is compared with the existing approaches described in the DEA literature to highlight its potential for performance assessments. The applicability of the method is illustrated with a case study that compares the performance of sections from stores with different brands (supermarkets versus hypermarkets). Only large supermarkets are compared with hypermarkets, such that the comparisons are only made between stores with similar scale size. The stores are organised in five different sections: grocery, perishables, light bazaar, heavy bazaar and textiles. The objective of the analysis is to determine if there is evidence that the sections of stores in hypermarkets perform better than the sections from stores in supermarkets. The study showed that there is evidence to conclude that the frontier of the sections in hypermarkets is more productive that the frontier of the sections in supermarkets. This conclusion is valid for the five sections analysed. However, the efficiency spread among sections within the same group did not differ between supermarkets and hypermarkets for all sections except for the heavy bazaar section. If the best practices of the heavy bazaar section are followed by the other sections in the same group, the scope for efficiency improvements is larger in hypermarkets than in supermarkets. In conclusion, we recommend changing the brand of large supermarket to the brand of hypermarkets, whenever this is compatible with the organisation requirements to label a store as an hypermarket. Hypermarkets seem to be more appealing to customers and to allow the attainment of higher productivity levels.
- Assessing the deployment of electric mobility: a reviewPublication . Gruetzmacher, Sarah; Vaz, Clara B.; Ferreira, Ângela P.The transport sector of the European Union is the only sector of the economy that has been increasing its emissions since 2014. To reduce the use of fossil fuels and achieve the greenhouse gas emissions mitigation target, many countries are focusing on the deployment of electric vehicles. This paper aims at analysing recent literature on the deployment of electric vehicles (EV) and typifying objectives, methods and indicators generally exploited, to better understand the state of the art on this topic. The Web of Science database was used and the results showed that the interest in the topic of electric vehicles has been increasing exponentially since 2010. The main significant indicators and the assessment methodologies were analysed. The indicators identified were aggregated in four main clusters: environmental, economic, social and technical indicators. Although the factors that contribute to EV deployment can vary depending on the regions specific characteristics, most of the research studies pointed out that the main contributors are the high density of recharging points, the existence of government monetary incentives and the lower operational cost of EV.
- Assessing the sustainable performance of the transport sector in European countries using alternative benefit-of-the-doubt modelsPublication . Gruetzmacher, Sarah; Vaz, Clara B.; Ferreira, Ângela P.The energy policy of the European Union stresses the need for sustainable energy consumption, improvements in energy efficiency and lower fossil fuel dependence in a decoupling strategy from unstable democracies. Transportation still represents a sector largely dependent on fossil fuels, which come with several negative impacts. Measuring and assessing the sustainability of the transport sector becomes necessary. This study aims to assess the sustainability performance of the transport sector across 28 European countries over a four-year period, aligned with the policy agenda outlined in strategic documents. The methodological approach involves applying Benefit-of-the-Doubt (BoD) models, comparing a version that uses transformation methods for antiisotonic sub-indicators with a variant that directly incorporates these sub-indicators as reverse indicators. In general, the European countries have improved the sustainability performance of their transport sector during the time span analyzed according to the results of both models. For the inefficient units, two improvement strategies are presented based on the profiles identified on the benchmarks from both models, which can be alternative stages to achieve the robust best practices of the benchmarks.
- Assessment of the transport sustainability performance in the European UnionPublication . Gruetzmacher, Sarah; Vaz, Clara B.; Ferreira, Ângela P.The transport sector plays a fundamental role in the European economy. By 2017, the transport sector employed directly more than 11 million people, around 57c of the total workforce, and its activities accounted for about 5% of Europe's Gross Domestic Product (GDP). Promoting efficient transport services and infrastructure is fundamental for making the most of the European's economic strengths, supporting the internal market and its growth. Unfortunately, the European Union transport sector still remains heavily dependent on oil resources and, therefore, it is responsible for a large part of the air pollution. The emissions from the sector have reduced in the last decade, but not enough to limit its impact on the environment and climate. Reducing its pressure on the environment is critical to achieve long-term sustainability. The European Union has been promoting diverse initiatives to- wards sustainable transport development and environment protection by setting targets for changes in the sector, as those proposed in the 2011 White Paper on transport [1]. This study aims at evaluating the sustainable performance of the transport sector in the 28 European Union countries, from 2015 to 2017, towards the policy agenda established in strategic documents. The assessment of the transport environmental performance was made through the aggregation of seven sub-indicators into a compos- ite indicator using a Data Envelopment Analysis approach. The model used to determine the weights to aggregate the sub-indicators is based on a variant of the Benefit of the Doubt model with virtual proportional weights restrictions as proposed by Färe et a1. [2] . The results indicate that, overall, the European Union countries had almost no variation on its transport environmental performance during the time span under analysis. The inefficient countries can improve the transport sustainability mainly by drastically reducing the greenhouse gas emissions from fossil fuels combustion, increasing the share of freight transport that uses rail and waterways and also the share of transport energy from renewable sources.