- Author(s)
- Nalan Basturk, Erasmus University Rotterdam; Cem Cakmakli, Koc University, Turkey; S. Pinar Ceyhan, Erasmus University Rotterdam; and Herman K. van Dijk, Erasmus University Rotterdam, the Netherlands
- Keywords:
- History, Bayesian Econometrics
- JEL codes:
- B04, C01
12 dezembro 2014
Crescimento da Econometria Bayesiana
This paper starts with a brief description of the introduction of the
likelihood approach in econometrics as presented in Cowles Foundation
Monographs 10 and 14. A sketch is given of the criticisms on this
approach mainly from the first group of Bayesian econometricians.
Publication and citation patterns of Bayesian econometric papers are
analyzed in ten major econometric journals from the late 1970s until the
first few months of 2014. Results indicate a cluster of journals with
theoretical and applied papers, mainly consisting of Journal of Econometrics, Journal of Business and Economic Statistics and Journal of Applied Econometrics
which contains the large majority of high quality Bayesian econometric
papers. A second cluster of theoretical journals, mainly consisting of Econometrica and Review of Economic Studies
contains few Bayesian econometric papers. The scientific impact,
however, of these few papers on Bayesian econometric research is
substantial. Special issues from the journals Econometric Reviews, Journal of Econometrics and Econometric Theory received wide attention. Marketing Science shows an ever increasing number of Bayesian papers since the middle nineties. The International Economic Review and the Review of Economics and Statistics
show a moderate time varying increase. An upward movement in
publication patterns in most journals occurs in the early 1990s due to
the effect of the 'Computational Revolution'. …
Fonte: On the Rise of Bayesian Econometrics after Cowles Foundation Monographs 10, 14
Normas novas
Mais normas:
A Comissão de Valores Mobiliários (CVM) edita hoje, 10/12/2014, a Deliberação nº 732/14 que aprova a Orientação Técnica OCPC 08 - Reconhecimento de Determinados Ativos ou Passivos nos relatórios Contábil-Financeiros de Propósito Geral das Distribuidoras de Energia Elétrica emitidos de acordo com as Normas Brasileiras e Internacionais de Contabilidade.
Além disto,
A Comissão de Valores Mobiliários (CVM) coloca em audiência pública hoje, 10/12/2014, minuta de deliberação que aprova o Documento de Revisão de Pronunciamentos Técnicos nº 07.
A Comissão de Valores Mobiliários (CVM) edita hoje, 10/12/2014, a Deliberação nº 732/14 que aprova a Orientação Técnica OCPC 08 - Reconhecimento de Determinados Ativos ou Passivos nos relatórios Contábil-Financeiros de Propósito Geral das Distribuidoras de Energia Elétrica emitidos de acordo com as Normas Brasileiras e Internacionais de Contabilidade.
Além disto,
A Comissão de Valores Mobiliários (CVM) coloca em audiência pública hoje, 10/12/2014, minuta de deliberação que aprova o Documento de Revisão de Pronunciamentos Técnicos nº 07.
11 dezembro 2014
Sophia Amoruso e Piketty
Vencedor do prêmio de melhor livro de negócios no "2014 Goodreads Choice Awards":
#GirlBoss de Sophia Amoruso - Ainda sem edição em português.
O livro de Piketty, "Capital", ficou em quinto. No Audible, todavia, ganhou como melhor audiobook de negócios. O livro do Google (How Google Works) ficou em terceiro - clique aqui para ler, em inglês, uma resenha do The Wall Street Journal.
Metrics: combatendo ciência de baixa qualidade
“WHY most published research findings are false” is not, as the title
of an academic paper, likely to win friends in the ivory tower. But it
has certainly influenced people (including journalists at The Economist).
The paper it introduced was published in 2005 by John Ioannidis, an
epidemiologist who was then at the University of Ioannina, in Greece,
and is now at Stanford. It exposed the ways, most notably the
overinterpreting of statistical significance in studies with small
sample sizes, that scientific findings can end up being
irreproducible—or, as a layman might put it, wrong.
Dr Ioannidis has been waging war on sloppy science ever since, helping to develop a discipline called meta-research (ie, research about research). Later this month that battle will be institutionalised, with the launch of the Meta-Research Innovation Centre at Stanford.
METRICS, as the new laboratory is to be known for short, will connect enthusiasts of the nascent field in such corners of academia as medicine, statistics and epidemiology, with the aim of solidifying the young discipline. Dr Ioannidis and the lab’s co-founder, Steven Goodman, will (for this is, after all, science) organise conferences at which acolytes can meet in the world of atoms, rather than just online. They will create a “journal watch” to monitor scientific publishers’ work and to shame laggards into better behaviour. And they will spread the message to policymakers, governments and other interested parties, in an effort to stop them making decisions on the basis of flaky studies. All this in the name of the centre’s nerdishly valiant mission statement: “Identifying and minimising persistent threats to medical-research quality.”
Irreproducibility is one such threat—so much so that there is an (admittedly tongue-in-cheek) publication called the Journal of Irreproducible Results.
Some fields are making progress, though. In psychology, the Many Labs
Replication Project, supported by the Centre for Open Science, an
institute of the University of Virginia, has re-run 13 experiments about
widely accepted theories. Only ten were validated. The centre has also
launched what it calls the Cancer Biology Reproducibility Project, to
look at 50 recent oncology studies.
Until now, however, according to Dr Ioannidis, no one has tried to find out whether such attempts at revalidation have actually had any impact on the credibility of research. METRICS will try to do this, and will make recommendations about how future work might be improved and better co-ordinated—for the study of reproducibility should, like any branch of science, be based on evidence of what works and what does not.
Wasted effort is another scourge of science that the lab will look into. A recent series of articles in the Lancet noted that, in 2010, about $200 billion (an astonishing 85% of the world’s spending on medical research) was squandered on studies that were flawed in their design, redundant, never published or poorly reported. METRICS will support efforts to tackle this extraordinary inefficiency, and will itself update research about the extent to which randomised-controlled trials acknowledge the existence of previous investigations of the same subject. If the situation has not improved, METRICS and its collaborators will try to design new publishing practices that discourage bad behaviour among scientists.
There is also Dr Ioannidis’s pet offender: publication bias. Not all studies that are conducted get published, and the ones which do tend to be those that have significant results. That leaves a skewed impression of the evidence.
Researchers have been studying publication bias for years, using various statistical tests. Again, though, there has been little reflection on these methods and their comparative effectiveness. They may, according to Dr Ioannidis, be giving both false negatives and false positives about whether or not publication bias exists in a particular body of studies.
Dr Ioannidis plans to run tests on the methods of meta-research itself, to make sure he and his colleagues do not fall foul of the very criticisms they make of others. “I don’t want”, he says, “to take for granted any type of meta-research is ideal and efficient and nice. I don’t want to promise that we can change the world, although this is probably what everybody has to promise to get funded nowadays.”
Fonte: aqui
Dr Ioannidis has been waging war on sloppy science ever since, helping to develop a discipline called meta-research (ie, research about research). Later this month that battle will be institutionalised, with the launch of the Meta-Research Innovation Centre at Stanford.
METRICS, as the new laboratory is to be known for short, will connect enthusiasts of the nascent field in such corners of academia as medicine, statistics and epidemiology, with the aim of solidifying the young discipline. Dr Ioannidis and the lab’s co-founder, Steven Goodman, will (for this is, after all, science) organise conferences at which acolytes can meet in the world of atoms, rather than just online. They will create a “journal watch” to monitor scientific publishers’ work and to shame laggards into better behaviour. And they will spread the message to policymakers, governments and other interested parties, in an effort to stop them making decisions on the basis of flaky studies. All this in the name of the centre’s nerdishly valiant mission statement: “Identifying and minimising persistent threats to medical-research quality.”
The METRICS system
Until now, however, according to Dr Ioannidis, no one has tried to find out whether such attempts at revalidation have actually had any impact on the credibility of research. METRICS will try to do this, and will make recommendations about how future work might be improved and better co-ordinated—for the study of reproducibility should, like any branch of science, be based on evidence of what works and what does not.
Wasted effort is another scourge of science that the lab will look into. A recent series of articles in the Lancet noted that, in 2010, about $200 billion (an astonishing 85% of the world’s spending on medical research) was squandered on studies that were flawed in their design, redundant, never published or poorly reported. METRICS will support efforts to tackle this extraordinary inefficiency, and will itself update research about the extent to which randomised-controlled trials acknowledge the existence of previous investigations of the same subject. If the situation has not improved, METRICS and its collaborators will try to design new publishing practices that discourage bad behaviour among scientists.
There is also Dr Ioannidis’s pet offender: publication bias. Not all studies that are conducted get published, and the ones which do tend to be those that have significant results. That leaves a skewed impression of the evidence.
Researchers have been studying publication bias for years, using various statistical tests. Again, though, there has been little reflection on these methods and their comparative effectiveness. They may, according to Dr Ioannidis, be giving both false negatives and false positives about whether or not publication bias exists in a particular body of studies.
Dr Ioannidis plans to run tests on the methods of meta-research itself, to make sure he and his colleagues do not fall foul of the very criticisms they make of others. “I don’t want”, he says, “to take for granted any type of meta-research is ideal and efficient and nice. I don’t want to promise that we can change the world, although this is probably what everybody has to promise to get funded nowadays.”
Fonte: aqui
10 dezembro 2014
Natura
Segundo a revista Época desta semana, a Natura tem como meta 50% dos cargos de chefia serem ocupados por mulheres até 2020.
Falhas Metodológicas das pesquisas empíricas em contabilidade
Some Methodological Deficiencies in Empirical
Research Articles in Accounting. Accounting Horizons: September 2014
Resumo:
This paper uses a sample of the regression and behavioral papers published in The Accounting Review and the Journal of Accounting Research from September 2012 through May 2013. We argue first that the current research results reported in empirical regression papers fail adequately to justify the time period adopted for the study. Second, we maintain that the statistical analyses used in these papers as well as in the behavioral papers have produced flawed results. We further maintain that their tests of statistical significance are not appropriate and, more importantly, that these studies do not—and cannot—properly address the economic significance of the work. In other words, significance tests are not tests of the economic meaningfulness of the results. We suggest ways to avoid some but not all of these problems. We also argue that replication studies, which have been essentially abandoned by accounting researchers, can contribute to our search for truth, but few will be forthcoming unless the academic reward system is modified.
Keywords: research methodology, statistical analysis
Resumo:
This paper uses a sample of the regression and behavioral papers published in The Accounting Review and the Journal of Accounting Research from September 2012 through May 2013. We argue first that the current research results reported in empirical regression papers fail adequately to justify the time period adopted for the study. Second, we maintain that the statistical analyses used in these papers as well as in the behavioral papers have produced flawed results. We further maintain that their tests of statistical significance are not appropriate and, more importantly, that these studies do not—and cannot—properly address the economic significance of the work. In other words, significance tests are not tests of the economic meaningfulness of the results. We suggest ways to avoid some but not all of these problems. We also argue that replication studies, which have been essentially abandoned by accounting researchers, can contribute to our search for truth, but few will be forthcoming unless the academic reward system is modified.
Keywords: research methodology, statistical analysis
Received: September 2013; Accepted: May 2014 ;Published Online: May 2014
Thomas R. Dyckman and Stephen A. Zeff
(2014) Some Methodological Deficiencies in Empirical
Research Articles in Accounting. Accounting Horizons: September 2014,
Vol. 28, No. 3, pp. 695-712.
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2324266
Thomas
R. Dyckman is a Professor Emeritus at Cornell University and an Adjunct
Professor at Florida Gulf Coast University, and Stephen A. Zeff is a
Professor at Rice University.
Recomendações dos Autores:
In summary we have endeavored to make the following points:
First, authors must adequately defend their selection of the sample period by convincing the reader that the period is stable itself and in relation to periods in close proximity.
Second, the accounting academy should actively seek and reward replications as an essential element in its aspirations to be a scientific community.
Third, authors should attend to the economic significance as well as the statistical significance of their investigations.
Fourth, authors should respect the limitation of conventional hypothesis tests applied to their data, which implies enhanced caution when declaring results to be statistically significant.
Fifth, authors could consider reporting the use of statistical intervals as a way to mitigate the problems of determining the most likely alternative hypothesis and thereby the appropriate Type ll error.
Sixth, authors need to be sure that, in their “Conclusions” section, they discuss the limitations of their research and how these limitations might be overcome, as well as suggest extensions for future research.
Seventh, authors should consider the use of descriptive statistics and other approaches as a means of, or support for, establishing the validity of their research objective.
Eighth, editors should consider requiring authors of accepted papers to provide a complete description of their methodology, including data collection, accuracy, and verification
Recomendações dos Autores:
In summary we have endeavored to make the following points:
First, authors must adequately defend their selection of the sample period by convincing the reader that the period is stable itself and in relation to periods in close proximity.
Second, the accounting academy should actively seek and reward replications as an essential element in its aspirations to be a scientific community.
Third, authors should attend to the economic significance as well as the statistical significance of their investigations.
Fourth, authors should respect the limitation of conventional hypothesis tests applied to their data, which implies enhanced caution when declaring results to be statistically significant.
Fifth, authors could consider reporting the use of statistical intervals as a way to mitigate the problems of determining the most likely alternative hypothesis and thereby the appropriate Type ll error.
Sixth, authors need to be sure that, in their “Conclusions” section, they discuss the limitations of their research and how these limitations might be overcome, as well as suggest extensions for future research.
Seventh, authors should consider the use of descriptive statistics and other approaches as a means of, or support for, establishing the validity of their research objective.
Eighth, editors should consider requiring authors of accepted papers to provide a complete description of their methodology, including data collection, accuracy, and verification
Piketty e suas lições para o Brasil
Roberto Macedo *
O Estado de S. Paulo, 4/12/2014
Thomas Piketty é um economista francês famoso internacionalmente após publicar, em 2013, o livro O Capital no Século XXI, um dos mais vendidos em vários países. Já existe também em português (Ed. Intrínseca, 2014).
Tem 43 anos e, aos 22, já era doutor em Economia. No biênio seguinte ensinou no famoso Massachusetts Institute of Technology, dos EUA. Tem outros livros, muitos artigos em boas revistas acadêmicas e recebeu premiações importantes. Convence, portanto, como personagem.
Na semana passada conheci-o na Faculdade de Economia, Administração e Contabilidade da USP. Almoçou com professores e deu palestra em inglês para um auditório cheio. Resumiu então esse seu livro e a apresentação está disponível piketty.pse.ens.fr/en/files/piketty2014capital21csaopaulo1.pdf.
A obra é densa em números e análise. A versão em inglês tem 685 páginas e dela traduzi trechos citados abaixo. Raramente toca no índice de Gini, que domina a análise da distribuição pessoal de renda no Brasil. Tal índice varia de zero a 1, da distribuição igualitária para a totalmente concentrada, mas sem chegar a esses extremos nas suas aplicações. E abandonou Gini: "... é impossível resumir uma realidade multidimensional com um índice unidimensional sem indevidamente simplificar as questões e misturar coisas que não deveriam ser tratadas conjuntamente". Por essa e outras razões, concluiu ser "muito melhor analisar desigualdades em termos de tabelas de distribuição indicando as parcelas dos vários decis e centis na renda total e na riqueza total..." (pág. 266). Decis e centis são, por exemplo, os 20% ou 1% mais ricos e suas parcelas desses totais. E no livro há perto de cem gráficos que facilitam entender seus muitos números.
Estudos sobre o Brasil ganhariam com esse enfoque. Assim, o livro também convence pelo que informa e tem de metodologia. Sua tese principal: "Quando a taxa de retorno sobre o capital excede significativamente a taxa de crescimento da economia (como aconteceu por muito tempo na História... e provavelmente também acontecerá no século XXI), a consequência lógica é que a riqueza herdada cresça mais do que a produção e a renda... Nessas condições, é quase inevitável que a riqueza herdada dominará e por grande margem a riqueza amealhada por uma vida de trabalho, e a concentração do capital atingirá níveis extremamente altos e potencialmente incompatíveis com os valores meritocráticos e princípios de justiça social fundamentais às sociedades democráticas modernas" (pág. 26). Discordo, pois se uma economia seguir crescendo, com todos melhorando de vida, ainda que uns mais e outros menos, mesmo estes poderão não ver injustiça social no processo.
O livro não cita o Brasil uma vez sequer. A distribuição de sua atenção se concentra em EUA, Japão, Alemanha, França e Grã Bretanha. No nosso país a concentração de renda é muito alta e os dados existentes não permitem analisar adequadamente a distribuição de riqueza. Mas basta andar por aí para ver que também é fortemente concentrada.
Quanto ao que fazer, novas discordâncias. Piketty prega uma "tributação progressiva e global do capital", o que "exigiria considerável grau de coordenação internacional" (pág. 27). Na palestra: essa tributação "seria baseada na troca automática de informações bancárias". Ora, não há como ter a aprovação unânime dessa ideia. Mais países se tornariam paraísos fiscais para cidadãos insatisfeitos de países aderentes, como já ocorre hoje com relação a países de tributos mais altos.
Voltando ao Brasil, na apresentação recomendou: "... precisa de mais transparência quanto a (dados de) renda e riqueza; tributação progressiva sobre a renda, herança e riqueza seriam uma forma poderosa de produzir informação sobre como os diferentes grupos de renda e de riqueza se beneficiam do crescimento".
Ora, para avançar nessa direção é fundamental atentar para as condições locais. O.k. para maior transparência e tributação progressiva de renda e herança. Aqui há impostos sobre renda em geral, propriedade imobiliária e herança, chamados de diretos, e na Constituição há o Imposto sobre Grandes Fortunas, que carece de lei complementar e vai ficando no armário. Ademais, entre outras dificuldades esse imposto interferiria com o IPTU e o Territorial Rural. Ambos carecem de cadastros que reflitam melhor o valor das respectivas propriedades, o que também poderia levar a uma cobrança mais realista e progressiva.
Ademais, estudos mostram que impostos indiretos, como ICMS, IPI e outros, predominantes na arrecadação tributária, são regressivos, pois incidem sobre o consumo, cuja participação nos gastos das pessoas decresce com a renda. Entre outras distorções, pesam muito nos preços e levam muitos brasileiros a comprar no exterior. Caberia diminuir o gravame desses impostos e ampliar o dos diretos. Nossa tributação não tem caráter e prefere esconder impostos nos preços.
Pode-se também melhorar as condições dos mais pobres atuando sobre os gastos públicos, como os do Bolsa Família. E não dar tanto aos mais ricos, como nos financiamentos subsidiados do BNDES. Na mesma linha, permanece por enfrentar o ensino superior público gratuito, no qual predominam alunos cujos pais poderiam pagar por ele, gerando recursos prioritariamente para bolsas de estudo para estudantes pobres que sem elas têm de trabalhar. Ou seja, é preciso ir do ensino gratuito para o estudante pago.
Também é indispensável ponderar que o Brasil ainda não é rico. Os países que Piketty observou mais têm renda por habitante com valor perto de quatro vezes a do Brasil. Assim, os brasileiros precisam ser estimulados a estudar, trabalhar, poupar e investir mais, acumulando mais capital nas suas várias formas, sem que a insaciável sede tributária do governo os desvie desse caminho.
*Roberto Macedo é economista (UFMG, USP e Harvard),
O Estado de S. Paulo, 4/12/2014
Thomas Piketty é um economista francês famoso internacionalmente após publicar, em 2013, o livro O Capital no Século XXI, um dos mais vendidos em vários países. Já existe também em português (Ed. Intrínseca, 2014).
Tem 43 anos e, aos 22, já era doutor em Economia. No biênio seguinte ensinou no famoso Massachusetts Institute of Technology, dos EUA. Tem outros livros, muitos artigos em boas revistas acadêmicas e recebeu premiações importantes. Convence, portanto, como personagem.
Na semana passada conheci-o na Faculdade de Economia, Administração e Contabilidade da USP. Almoçou com professores e deu palestra em inglês para um auditório cheio. Resumiu então esse seu livro e a apresentação está disponível piketty.pse.ens.fr/en/files/piketty2014capital21csaopaulo1.pdf.
A obra é densa em números e análise. A versão em inglês tem 685 páginas e dela traduzi trechos citados abaixo. Raramente toca no índice de Gini, que domina a análise da distribuição pessoal de renda no Brasil. Tal índice varia de zero a 1, da distribuição igualitária para a totalmente concentrada, mas sem chegar a esses extremos nas suas aplicações. E abandonou Gini: "... é impossível resumir uma realidade multidimensional com um índice unidimensional sem indevidamente simplificar as questões e misturar coisas que não deveriam ser tratadas conjuntamente". Por essa e outras razões, concluiu ser "muito melhor analisar desigualdades em termos de tabelas de distribuição indicando as parcelas dos vários decis e centis na renda total e na riqueza total..." (pág. 266). Decis e centis são, por exemplo, os 20% ou 1% mais ricos e suas parcelas desses totais. E no livro há perto de cem gráficos que facilitam entender seus muitos números.
Estudos sobre o Brasil ganhariam com esse enfoque. Assim, o livro também convence pelo que informa e tem de metodologia. Sua tese principal: "Quando a taxa de retorno sobre o capital excede significativamente a taxa de crescimento da economia (como aconteceu por muito tempo na História... e provavelmente também acontecerá no século XXI), a consequência lógica é que a riqueza herdada cresça mais do que a produção e a renda... Nessas condições, é quase inevitável que a riqueza herdada dominará e por grande margem a riqueza amealhada por uma vida de trabalho, e a concentração do capital atingirá níveis extremamente altos e potencialmente incompatíveis com os valores meritocráticos e princípios de justiça social fundamentais às sociedades democráticas modernas" (pág. 26). Discordo, pois se uma economia seguir crescendo, com todos melhorando de vida, ainda que uns mais e outros menos, mesmo estes poderão não ver injustiça social no processo.
O livro não cita o Brasil uma vez sequer. A distribuição de sua atenção se concentra em EUA, Japão, Alemanha, França e Grã Bretanha. No nosso país a concentração de renda é muito alta e os dados existentes não permitem analisar adequadamente a distribuição de riqueza. Mas basta andar por aí para ver que também é fortemente concentrada.
Quanto ao que fazer, novas discordâncias. Piketty prega uma "tributação progressiva e global do capital", o que "exigiria considerável grau de coordenação internacional" (pág. 27). Na palestra: essa tributação "seria baseada na troca automática de informações bancárias". Ora, não há como ter a aprovação unânime dessa ideia. Mais países se tornariam paraísos fiscais para cidadãos insatisfeitos de países aderentes, como já ocorre hoje com relação a países de tributos mais altos.
Voltando ao Brasil, na apresentação recomendou: "... precisa de mais transparência quanto a (dados de) renda e riqueza; tributação progressiva sobre a renda, herança e riqueza seriam uma forma poderosa de produzir informação sobre como os diferentes grupos de renda e de riqueza se beneficiam do crescimento".
Ora, para avançar nessa direção é fundamental atentar para as condições locais. O.k. para maior transparência e tributação progressiva de renda e herança. Aqui há impostos sobre renda em geral, propriedade imobiliária e herança, chamados de diretos, e na Constituição há o Imposto sobre Grandes Fortunas, que carece de lei complementar e vai ficando no armário. Ademais, entre outras dificuldades esse imposto interferiria com o IPTU e o Territorial Rural. Ambos carecem de cadastros que reflitam melhor o valor das respectivas propriedades, o que também poderia levar a uma cobrança mais realista e progressiva.
Ademais, estudos mostram que impostos indiretos, como ICMS, IPI e outros, predominantes na arrecadação tributária, são regressivos, pois incidem sobre o consumo, cuja participação nos gastos das pessoas decresce com a renda. Entre outras distorções, pesam muito nos preços e levam muitos brasileiros a comprar no exterior. Caberia diminuir o gravame desses impostos e ampliar o dos diretos. Nossa tributação não tem caráter e prefere esconder impostos nos preços.
Pode-se também melhorar as condições dos mais pobres atuando sobre os gastos públicos, como os do Bolsa Família. E não dar tanto aos mais ricos, como nos financiamentos subsidiados do BNDES. Na mesma linha, permanece por enfrentar o ensino superior público gratuito, no qual predominam alunos cujos pais poderiam pagar por ele, gerando recursos prioritariamente para bolsas de estudo para estudantes pobres que sem elas têm de trabalhar. Ou seja, é preciso ir do ensino gratuito para o estudante pago.
Também é indispensável ponderar que o Brasil ainda não é rico. Os países que Piketty observou mais têm renda por habitante com valor perto de quatro vezes a do Brasil. Assim, os brasileiros precisam ser estimulados a estudar, trabalhar, poupar e investir mais, acumulando mais capital nas suas várias formas, sem que a insaciável sede tributária do governo os desvie desse caminho.
*Roberto Macedo é economista (UFMG, USP e Harvard),
09 dezembro 2014
Curso de Contabilidade Básica: Queima de Caixa
A empresa Moody´s alertou sobre a possibilidade de queima de caixa na empresa Petrobras (ver ROSTÁS, Renato. Moody´s alerta sobre queima de caixa na Petrobras. Valor Econômico, 5 de dezembro de 2014). O termo refere-se ao fato da empresa reduzir o volume de recursos existentes no caixa. O alerta indica que isto poderá ocorrer depois de 2016, a persistir a situação da empresa. A Moody´s baseou na impossibilidade da empresa em cortar seus investimentos, que já estão comprometidos.
Vamos observar como isto ocorre através da figura abaixo:
As quatro linhas mostram a evolução do início de 2008 até o segundo trimestre de 2014, quando foram divulgadas as últimas demonstrações da empresa. Observe a linha azul, que mostra o volume de caixa de equivalentes. De um valor em torno de 40 bilhões de reais entre 2010 a 2013, a empresa tinha, em 30 de junho de 2014, 58 bilhões. Considerando que a empresa irá necessitar de 5 bilhões de reais por trimestre, isto significa que a empresa poderia levar 11 trimestres para queimar este caixa. Observe que a empresa está gerando, por trimestre, algo em torno de 13 bilhões de reais por trimestre, o que permite investimentos de 18 bilhões (= 13 mais 5).
A linha roxa mostra a soma do fluxo operacional e de investimento. Durante quase todo o período esta linha ficou abaixo de zero. Em média a soma dos fluxos foi de 5 bilhões negativos. Ou seja, esta diferença tem sido financiada por empréstimos ou acionistas. Se mantiver esta média, teremos novamente 11 trimestres para queimar este caixa. Mas observe que quando uma empresa está em dificuldades – como é o caso da Petrobrás - isto tende a refletir no prazo concedido pelos fornecedores, no aumento dos custos de aquisição e nos custos dos empréstimos.
Observe agora o leitor a linha vermelha. Ela indica o caixa, equivalentes e título e valores mobiliários (de curto e longo prazo). Seria uma espécie de caixa “amplo”. Note que a diferença entre estes valores e o caixa mais “restrito” reduziu a partir de 2013. Ou seja, nos últimos trimestres a empresa já estava “queimando” seu caixa “amplo”.
Em suma, o alerta da Moody´s faz sentido e, como afirma a entidade, isto ainda irá demorar ocorrer no curto prazo, mesmo nos piores cenários.
Vamos observar como isto ocorre através da figura abaixo:
As quatro linhas mostram a evolução do início de 2008 até o segundo trimestre de 2014, quando foram divulgadas as últimas demonstrações da empresa. Observe a linha azul, que mostra o volume de caixa de equivalentes. De um valor em torno de 40 bilhões de reais entre 2010 a 2013, a empresa tinha, em 30 de junho de 2014, 58 bilhões. Considerando que a empresa irá necessitar de 5 bilhões de reais por trimestre, isto significa que a empresa poderia levar 11 trimestres para queimar este caixa. Observe que a empresa está gerando, por trimestre, algo em torno de 13 bilhões de reais por trimestre, o que permite investimentos de 18 bilhões (= 13 mais 5).
A linha roxa mostra a soma do fluxo operacional e de investimento. Durante quase todo o período esta linha ficou abaixo de zero. Em média a soma dos fluxos foi de 5 bilhões negativos. Ou seja, esta diferença tem sido financiada por empréstimos ou acionistas. Se mantiver esta média, teremos novamente 11 trimestres para queimar este caixa. Mas observe que quando uma empresa está em dificuldades – como é o caso da Petrobrás - isto tende a refletir no prazo concedido pelos fornecedores, no aumento dos custos de aquisição e nos custos dos empréstimos.
Observe agora o leitor a linha vermelha. Ela indica o caixa, equivalentes e título e valores mobiliários (de curto e longo prazo). Seria uma espécie de caixa “amplo”. Note que a diferença entre estes valores e o caixa mais “restrito” reduziu a partir de 2013. Ou seja, nos últimos trimestres a empresa já estava “queimando” seu caixa “amplo”.
Em suma, o alerta da Moody´s faz sentido e, como afirma a entidade, isto ainda irá demorar ocorrer no curto prazo, mesmo nos piores cenários.
Curso de Contabilidade Básica - Editora Atlas - César Augusto Tibúrcio Silva e Fernanda Fernandes
Rodrigues (prelo)
Comportamento dos pobres e desenvolvimento econômico
A BAT and a ball cost $1.10 between them. The bat costs $1 more than
the ball. How much does each cost? By paying attention to how people
actually think, behavioural economics has qualified some of the
underlying assumptions of classical economics, notably that everyone is
perfectly rational. In fact, the mind plays tricks, dividing up $1.10
(in this example) neatly into $1 and 10 cents, rather than correctly
into $1.05 and 5 cents. People also tend to copy others and often prefer
to co-operate rather than compete. For these reasons, some of the
simplifying assumptions of economics are not always correct: people do
not act in every instance in their long-term self-interest; they do not
weigh up all the costs and benefits before taking a decision.
Many of the insights of behavioural economics were based on studies of American university students and other privileged folk. But they apply with greater force to the poor—both the poor in rich countries and the more numerous inhabitants of developing ones. Behavioural economics therefore has profound implications for development. The new “World Development Report”, the flagship publication of the World Bank, considers them.
As the report shows, the poor are more likely than other people to make bad economic decisions. This is not because they are irrational or foolish but because so much is stacked against them. They are more likely to lack the basic information needed to make good choices, such as which fertiliser to use or when to apply it. They are more likely to live in societies which hold mistaken or harmful views, such as that girls should not go to school.
Conventional economic thinking assumes the poor will want to earn their way out of poverty. But as studies from countries as different as Ethiopia and France show, poverty makes people feel powerless and blunts their aspirations, so they may not even try to improve their lot. When they do, they face obstacles everywhere. They have no margin for error, making them risk averse. If they do not know where their next meal is coming from, saving and investing for the future is hard. George Orwell said, “Within certain limits, the less money you have the less you worry.” He was wrong. The poor are subject to exceptional levels of stress: childhood sickness is more likely to be life-threatening; crop failure can lead to destitution. And stress makes good decision-making harder. Above all, the poor lack the institutional framework which, in the West, improves decisions. Everywhere, people underestimate the benefits of education and save too little for their retirement. But children in the West go to school as a matter of course; pension systems make some savings automatic. Poor countries provide few such props.
All this helps explain why the poor stay poor; why (for example) subsistence farmers do not buy fertiliser or put children into secondary school, though they would benefit from doing so. More important, though, behavioural economics provides a different way of thinking about some of the problems of poverty.
Traditional development programmes stress resources and markets. People are poor, the argument goes, because they lack resources: not just money but roads, clinics, schools and irrigation canals. The job of development is to provide those things. And since resources also need to be allocated properly, prices have to be right. So a lot of development is about freeing prices and making markets more efficient.
A behavioural approach to development is different. It focuses on how decisions are made and how they can be improved. For example, in Bogotá a conditional-cash transfer programme paid mothers a monthly stipend if they took their children to school. Attendance during the school year was good but re-enrolment rates were low. A shift in the timing of the hand-out—withholding a part of the regular payment until just before the start of the school year—boosted enrolment sharply. This makes little sense in conventional economic terms: going to school is so beneficial that families should not need extra incentives and the overall sum available did not change. Yet the pay-off was substantial.
Actions like this sound marginal. Economists should be paying attention to the details of policy anyway. It may not seem to amount to a profoundly different approach—but it actually might.
Some small-scale policies turn out to be far from marginal. A
programme in Jamaica in the 1990s taught mothers of chronically
malnourished toddlers how to play with them in such a way as to
encourage greater verbal and physical skills—a behavioural tweak. Twenty
years later, the average earnings of these children (among the most
deprived in the country) were higher than those of children who had not
been malnourished, and far higher than malnourished children who were
not part of the programme. Paying attention to how the poor actually
think would also imply big changes to financial-inclusion policies,
encouraging financial products that people want to buy.
Moreover, development experts have their biases and blind spots, like anyone else. In principle, behavioural development could sit happily alongside the traditional sort. In practice, the two will compete for resources and professional attention.
A behavioural approach to poverty is not new. The World Bank has long had a behavioural unit. The Poverty Action Lab at the Massachusetts Institute of Technology has championed randomised control trials to test tweaks to policy. But by making this the subject of its main annual publication, the Bank has brought behavioural economics into the mainstream of development. It is likely to prove a challenge to traditional ways of combating poverty, as well as a complement to them.
Fonte: aqui
Many of the insights of behavioural economics were based on studies of American university students and other privileged folk. But they apply with greater force to the poor—both the poor in rich countries and the more numerous inhabitants of developing ones. Behavioural economics therefore has profound implications for development. The new “World Development Report”, the flagship publication of the World Bank, considers them.
As the report shows, the poor are more likely than other people to make bad economic decisions. This is not because they are irrational or foolish but because so much is stacked against them. They are more likely to lack the basic information needed to make good choices, such as which fertiliser to use or when to apply it. They are more likely to live in societies which hold mistaken or harmful views, such as that girls should not go to school.
Conventional economic thinking assumes the poor will want to earn their way out of poverty. But as studies from countries as different as Ethiopia and France show, poverty makes people feel powerless and blunts their aspirations, so they may not even try to improve their lot. When they do, they face obstacles everywhere. They have no margin for error, making them risk averse. If they do not know where their next meal is coming from, saving and investing for the future is hard. George Orwell said, “Within certain limits, the less money you have the less you worry.” He was wrong. The poor are subject to exceptional levels of stress: childhood sickness is more likely to be life-threatening; crop failure can lead to destitution. And stress makes good decision-making harder. Above all, the poor lack the institutional framework which, in the West, improves decisions. Everywhere, people underestimate the benefits of education and save too little for their retirement. But children in the West go to school as a matter of course; pension systems make some savings automatic. Poor countries provide few such props.
All this helps explain why the poor stay poor; why (for example) subsistence farmers do not buy fertiliser or put children into secondary school, though they would benefit from doing so. More important, though, behavioural economics provides a different way of thinking about some of the problems of poverty.
Traditional development programmes stress resources and markets. People are poor, the argument goes, because they lack resources: not just money but roads, clinics, schools and irrigation canals. The job of development is to provide those things. And since resources also need to be allocated properly, prices have to be right. So a lot of development is about freeing prices and making markets more efficient.
A behavioural approach to development is different. It focuses on how decisions are made and how they can be improved. For example, in Bogotá a conditional-cash transfer programme paid mothers a monthly stipend if they took their children to school. Attendance during the school year was good but re-enrolment rates were low. A shift in the timing of the hand-out—withholding a part of the regular payment until just before the start of the school year—boosted enrolment sharply. This makes little sense in conventional economic terms: going to school is so beneficial that families should not need extra incentives and the overall sum available did not change. Yet the pay-off was substantial.
Actions like this sound marginal. Economists should be paying attention to the details of policy anyway. It may not seem to amount to a profoundly different approach—but it actually might.
A tweaking revolution
Moreover, development experts have their biases and blind spots, like anyone else. In principle, behavioural development could sit happily alongside the traditional sort. In practice, the two will compete for resources and professional attention.
A behavioural approach to poverty is not new. The World Bank has long had a behavioural unit. The Poverty Action Lab at the Massachusetts Institute of Technology has championed randomised control trials to test tweaks to policy. But by making this the subject of its main annual publication, the Bank has brought behavioural economics into the mainstream of development. It is likely to prove a challenge to traditional ways of combating poverty, as well as a complement to them.
Fonte: aqui
Novamente a Convergência
Os Estados Unidos têm enfretado uma pressão do G20 em harmonizar sua contabilidade com as IFRS, usada em mais de 100 países do mundo. Apesar do namoro entre a SEC e o Iasb, o regulador das normas internacionais, os Estados Unidos não apresentam segurança pela opção das IFRS. Mas Schnurr afirmou que espera conversar com os comissários da SEC sobre as alternativas para uma mudança nas normas. Isto seria uma mudança da atitude que após as críticas realizadas em 2012 distanciaram da adoção.
Mas a Financial Accounting Foundation fez uma comunicado ontem afirmando:
We agree with Chief Accountant Schnurr that U.S. investors are best served by an independent standard setter that is first focused on the interests of those who participate in U.S. capital markets.
Ou seja, acreditamos no que fazemos aqui, nos EUA. As IFRS seriam uma informação adicional. Um balde de água fria.
VDM: Publicar a dissertação de graça?
“Prezado [autor]:
Dirijo-me a você em representação da editora Novas Edições Acadêmicas.
Encontramos uma referência ao seu trabalho intitulado “[título]“, consultando a base de dados da [instituição de ensino superior].
Me comunico com você para oferecer-lhe a oportunidade de publicá-lo em forma de livro impresso de maneira gratuita.”
Minha primeira reação: “Piá, que massa! Vou publicar “de grátis”!“
Segundos depois lembrei dos amigos que já publicaram seus trabalhos acadêmicos, e como foi difícil para muitos ter de arcar com os custos de edição, tiragem mínima, revisão, distribuição, etc.
Segunda reação: “Quando a esmola é demais…“ [Ou: não exste almoço grátis].
Resolvi pesquisar no Google o nome da editora, mas não encontrei queixas. Então usei o nome da empresa responsável pela editora.
O grupo responsável pela marca é o VDM Publishing, grupo alemão, também responsável pela editora Lambert Academic Publishing (LAP). Usando o nome da LAP no Google, você encontrará inúmeras críticas ao grupo. Sugiro darem uma olhada nestes blogs:
1. Lambert Academic Publishing Continues to Spam
2. Why You Shouldn’t Publish with Lap Lambert, German Publishing House
3. Behind Lambert Academic Publishing’s marketing gimmick
4. Lambert Academic Publishing (or How Not to Publish Your Thesis)
Resumidamente, a prática do VDM é a seguinte: eles entram em contato com vários autores, dizendo que irão “publicar” o livro de graça. Na verdade, o que eles fazem é fornecer uma edição digital da sua dissertação ou monografia, com a capa da editora. Todo o trabalho de revisão de texto fica com o autor. Se você quiser seu livro impresso, terá de pagar. E não é barato (o site cobra em euro!), além da qualidade do material não ser das melhores.
Não vejo problemas com o estilo “on demand” em editoras que prezam pela qualidade do texto publicado, mas o que dizer das editoras do grupo VDM? Elas sequer fazem a revisão do texto ou solicitam a análise da obra por especialistas na área.
Terceira reação: “Mas se eles querem publicar em formato de livro um trabalho que já está disponível na internet, por que não?“.
Literalmente falando, seria como pegar minha dissertação, colocar uma capa com a minha foto, nome de editora e número de ISBN. O problema é que eu consultei a base do ISBN e não encontrei a editora NEA. Testei os números de ISBN de algumas obras do catálogo da editora e nenhuma constava na base.
Lá fora, ter a obra publicada por uma editora VDM não rende muitos pontos. O grupo se aproveita da máquina de produção de textos que virou o mundo científico: ter um bom currículo implica ter muitas publicações (lattes, um beijo grande!), e diante da possibilidade de publicar de graça uma dissertação ou monografia em formato de livro, quem resiste?
Mas é bom ficar de olho: caso queria publicar pelas editoras do grupo VDM, considere o risco de ceder os direitos de sua obra a um grupo internacionalmente criticado.
Texto escrito por Wellington Oliveira dos Santos – Doutorando em Educação via Pos-Graduando
Listas: As maiores empresas de Tv por assinatura
2. Sky = 5.624
3. Gatonet = 4.200
4. Oi = 964
5. GVT = 821
6. Telefônica = 714
7. Big Brasil = 157
8. Algar = 127
9. Nossa TV = 116
10. Cabo = 49
11. Outros = 413 mil
Fonte: Associação Brasileira das Tvs por Assinatura e Aneel
08 dezembro 2014
Por que os economistas são tão influentes?
“IF ECONOMISTS could manage to get themselves thought of as humble,
competent people, on a level with dentists, that would be splendid!”
said John Maynard Keynes, a British economist. Despite their collective
failure to predict the financial crisis, let alone follow Keynes’s
injunction, economists are still very influential. They write newspaper
columns, advise politicians and offer expensive consulting services to
business-folk far more than other academics. A new paper* tries to
explain why.
One reason, say the authors, is that economists have come to believe that they are superior. A survey in 1985 found that just 9% of graduate students in economics at Harvard strongly believed that economics was “the most scientific of the social sciences”. But as economics became ever more mathematical, its practitioners grew in self-confidence. By 2003 54% of the graduate economists studying at Harvard strongly agreed with the statement. A glance at a popular blog for doctoral students in economics, econjobrumors.com, gives a taste of the contempt in which its users hold other disciplines. Sociologists “play around with big important ideas without too much effort or rigour,” one econo-nerd asserts.
The authors point out that economists demonstrate their self-belief in subtler ways too. Articles in the American Economic Review cite the top 25 political-science journals one-fifth as often as the articles in the American Political Science Review cite the top 25 economics journals. Another study found that American economics professors were less likely than their peers in other subjects to agree with the notion that “interdisciplinary knowledge is better than knowledge obtained by a single discipline.”
The odd thing, the authors argue, is that we believe in economists almost as much as they believe in themselves. Journalists and politicians seek strong arguments and clear answers. Most academics are reticent types: historians, for instance, question whether you can learn anything from history. “For a moderate fee,” jokes Deirdre McCloskey, an economic historian, “an economist will tell you with all the confidence of a witch doctor that interest rates will rise 56 basis points next month or that dropping agricultural subsidies will increase Swiss national income by 14.8%.”
* “The superiority of economists”, by M. Fourcade, E. Ollion and Y. Algan, MaxPo Discussion Paper 14/3.
Fonte: aqui
One reason, say the authors, is that economists have come to believe that they are superior. A survey in 1985 found that just 9% of graduate students in economics at Harvard strongly believed that economics was “the most scientific of the social sciences”. But as economics became ever more mathematical, its practitioners grew in self-confidence. By 2003 54% of the graduate economists studying at Harvard strongly agreed with the statement. A glance at a popular blog for doctoral students in economics, econjobrumors.com, gives a taste of the contempt in which its users hold other disciplines. Sociologists “play around with big important ideas without too much effort or rigour,” one econo-nerd asserts.
The authors point out that economists demonstrate their self-belief in subtler ways too. Articles in the American Economic Review cite the top 25 political-science journals one-fifth as often as the articles in the American Political Science Review cite the top 25 economics journals. Another study found that American economics professors were less likely than their peers in other subjects to agree with the notion that “interdisciplinary knowledge is better than knowledge obtained by a single discipline.”
The odd thing, the authors argue, is that we believe in economists almost as much as they believe in themselves. Journalists and politicians seek strong arguments and clear answers. Most academics are reticent types: historians, for instance, question whether you can learn anything from history. “For a moderate fee,” jokes Deirdre McCloskey, an economic historian, “an economist will tell you with all the confidence of a witch doctor that interest rates will rise 56 basis points next month or that dropping agricultural subsidies will increase Swiss national income by 14.8%.”
* “The superiority of economists”, by M. Fourcade, E. Ollion and Y. Algan, MaxPo Discussion Paper 14/3.
Fonte: aqui
07 dezembro 2014
Pressão dos Pares no avião
So you’re sitting on a plane, somewhere in the back. Sweat is rising
off this human stew, and in horror you watch it condense, trickling down
the window glass. You slam the blind shut. Eww.
Of course the feeling is irrational—you’re flying, through the sky!—but you hate everything right now. The airline, for its stinginess. The flight attendant, for pouring you half a can of Coke, then taking the can back. But most of all, you hate your fellow passengers. You hate humanity.
Someone next to you swipes his credit card to buy an in-flight movie, which again reminds you of the insult, the nickel and diming, of air travel.
And yet. After analyzing a confidential database of passenger and time-stamped purchase records, a Stanford professor discovered that if someone next to you buys something on the plane, you’re 30 percent more likely to buy something yourself.
That’s the power of peer pressure.
In a recent working paper, Pedro Gardete looked at 65,525 transactions across 1,966 flights and more than 257,000 passengers. He parsed the data into thousands of mini-experiments such as this:
If someone beside you ordered a snack or a film, Gardete was able to see whether later you did, too. In this natural experiment, the person sitting directly in front of you was the control subject. Purchases were made on a touchscreen; that person wouldn’t have been able to see anything. If you bought something, and the person in front of you didn’t, peer pressure may have been the reason.
Because he had reservation data, Gardete could exclude people flying together, and he controlled for all kinds of other factors such as seat choice. This is purely the effect of a stranger’s choice — not just that, but a stranger whom you might be resenting because he is sitting next to you, and this is a plane.
By adding up thousands of these little experiments, Gardete, an assistant professor of marketing at Stanford, came up with an estimate. On average, people bought stuff 15 to 16 percent of the time. But if you saw someone next to you order something, your chances of buying something, too, jumped by 30 percent, or about four percentage points.
“That magnitude I really didn’t expect,” Gardete says. “It’s crazy, crazy.”
The beauty of this paper is that it looks at social influences in a controlled situation. (What’s more of a trap than an airplane seat?) These natural experiments are hard to come by.
Economists and social scientists have long wondered about the power of peer pressure, but it’s one of the trickiest research problems.
“Social effects in consumption are very hard to measure,” Gardete says. “Just think of a supermarket. The number of things happening in a supermarket are so huge that it’s very hard to measure anything.”
[...]
Fonte: aqui
Of course the feeling is irrational—you’re flying, through the sky!—but you hate everything right now. The airline, for its stinginess. The flight attendant, for pouring you half a can of Coke, then taking the can back. But most of all, you hate your fellow passengers. You hate humanity.
Someone next to you swipes his credit card to buy an in-flight movie, which again reminds you of the insult, the nickel and diming, of air travel.
And yet. After analyzing a confidential database of passenger and time-stamped purchase records, a Stanford professor discovered that if someone next to you buys something on the plane, you’re 30 percent more likely to buy something yourself.
That’s the power of peer pressure.
In a recent working paper, Pedro Gardete looked at 65,525 transactions across 1,966 flights and more than 257,000 passengers. He parsed the data into thousands of mini-experiments such as this:
If someone beside you ordered a snack or a film, Gardete was able to see whether later you did, too. In this natural experiment, the person sitting directly in front of you was the control subject. Purchases were made on a touchscreen; that person wouldn’t have been able to see anything. If you bought something, and the person in front of you didn’t, peer pressure may have been the reason.
Because he had reservation data, Gardete could exclude people flying together, and he controlled for all kinds of other factors such as seat choice. This is purely the effect of a stranger’s choice — not just that, but a stranger whom you might be resenting because he is sitting next to you, and this is a plane.
By adding up thousands of these little experiments, Gardete, an assistant professor of marketing at Stanford, came up with an estimate. On average, people bought stuff 15 to 16 percent of the time. But if you saw someone next to you order something, your chances of buying something, too, jumped by 30 percent, or about four percentage points.
“That magnitude I really didn’t expect,” Gardete says. “It’s crazy, crazy.”
The beauty of this paper is that it looks at social influences in a controlled situation. (What’s more of a trap than an airplane seat?) These natural experiments are hard to come by.
Economists and social scientists have long wondered about the power of peer pressure, but it’s one of the trickiest research problems.
“Social effects in consumption are very hard to measure,” Gardete says. “Just think of a supermarket. The number of things happening in a supermarket are so huge that it’s very hard to measure anything.”
[...]
Fonte: aqui
Joy Sun: Será que você deveria doar de forma diferente?
A tecnologia nos permite doar dinheiro diretamente às pessoas mais pobres do planeta. Devemos fazer isso? Nesta palestra instigante, Joy Sun, veterana em assistência humanitária, aborda duas formas de ajudar os pobres.
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