06 agosto 2019
Introdução à Contabilidade | Prof. Odair Correa
Eu fico muito feliz ao ver o pessoal da minha turma de mestrado conquistando o mundo por aí. Hoje o Odair nos enviou um vídeo, pois está adentrando o mundo do ensino a distância. No vídeo ele faz uma excelente introdução à contabilidade.
Sucesso, amigo querido! Você nasceu pra isso!!
05 agosto 2019
Siga o dinheiro
Um documento do Centro Stigler (via aqui) mostra que a crítica ao uso do rastreamento financeiro para descobrir o foco do terrorismo pode ser inadequado. O documento mostra que é possível reduzir os ataques de terroristas a partir de um estudo realizado no Paquistão.
Primeiro, o financiamento do terrorismo afeta o tipo de ataque terrorista que estão sendo planejados. (...) Em segundo lugar, [há] aumento dos ataques que está ligado aos grupos terroristas que desfrutam de um aumento no financiamento.
Outra situação foi revelado pelo ProPublica e WSJournal (via aqui) que alguns pais evitam o custo das mensalidades da faculdade nos EUA. Em alguns lugares, há ajuda financeira para os “necessitados”. Os país, para obterem este tipo de ajuda, “desistem” da custódia dos filhos. E assim, podem se qualificar para auxílios. Este tipo de fraude ocorre pelo fato do custo da educação estar aumentando nos últimos anos.
03 agosto 2019
Big Data e Pesquisa em Ciências Humanas/Sociais
As vantagens são: big, always-on e não reativo. O que significa isto? Segundo Salganik, o fato de termos um grande número de dados permite que o pesquisador possa estudar eventos que são raros, estudar a heterogeneidade de maneira mais completa (eu posso pesquisar o homem branco, que vive em Brasília, com idade de 20 anos e que torce para o América de Natal) e conseguir detectar diferenças que são pequenas. A segunda grande vantagem é o fato de estar constantemente coletando informações. Se uso o Twitter para saber como as pessoas estão pensando sobre a economia, posso fazer uma pesquisa com as últimas mensagens que foram postadas. Finalmente, a base de dados onde podemos obter um grande número de informações geralmente são não reativas. Ou seja, o comportamento das pessoas não muda por estarem sendo observadas ou suas opiniões não se alteram na frente de um pesquisador. Assim, uma pessoa que está pesquisando no "search" do Google tenderá a ser mais verdadeiro que aquela pessoas diante de uma questão de uma pesquisa (vide o que diz o livro Todo Mundo Mente)
Mas o uso do big data em pesquisa possui sete inconvenientes. Alguns dos problemas apontados podem ser solucionados. Mas não deixam de representar um risco para qualidade da pesquisa. Os problemas são: incompletude, inacessibilidade, não representatividade, drifting, influenciado pelo algoritmo, sujeira e o fato de ser sensível. Em geral informações derivadas de big data não foram feitas para a sua pesquisa.Isto significa dizer que nem toda informação estará disponível. Se desejo saber o efeito da raça na escolha de um time de futebol, talvez não tenha esta informação no Facebook. Assim, o big data geralmente é falho nas informações demográficas. É possível resolver parte deste problema com técnicas, como imputação ou fazendo cruzamento de bases diferentes.
Um segundo problema é a inacessibilidade. Poucos pesquisadores possuem acesso da base de dados do Facebook. E quando conseguem este acesso, precisam fazer compromissos que podem prejudicar a pesquisa. A questão da inacessibilidade é muito menos uma barreira tecnológica do que problemas legais, éticos e de negócios.
Grande número de dados é bom para pesquisa, mas muitas vezes eles não representam a população de maneira adequada. A não representatividade faz com que uma pesquisa usando as postagens do Twitter não sejam representativos já que está restrito as pessoas que possuem conta nesta rede social e utilizam de maneira regular. Assim como Salganik, não acredito que isto seja um empecilho para pesquisa. O autor faz uma discussão importante ao lembrar que dificilmente uma amostra da população consegue ser realmente representativa em todos os aspectos.
Drifting significa aqui mudança. Grandes bases de dados precisam lidar com mudanças na forma como as pessoas usam um sistema, que pessoas usam o sistema e com as mudanças do sistema. Parece-me que o Facebook teve, ao longo do tempo, este tipo de mudança: inicialmente, a rede social no Brasil era predominantemente habitada por jovens; com o tempo, pessoas mais idosas passaram a se cadastrar na rede. Muitos jovens transferiram sua preferência para o Instagram, nos anos recentes. Este tipo de mudança pode alterar os resultados coletados com dados do Facebook, por exemplo.
Uma mudança técnica ocorre no próprio algoritmo. Recentemente, uma rede social passou a não divulgar mais o número de likes em cada postagem. Isto naturalmente afeta os dados coletados nesta rede social. Este problema é importante, já que muitos sites estão mudando constantemente sua configuração, procurando maximizar o tempo de navegação do usuário no mesmo. Se estas mudanças não estão documentadas, podem influenciar os resultados obtidos nas pesquisas.
As fontes de um grande número de dados geralmente são sujas. Ou seja, são afetadas por porcarias, como spam. O número de hastags pode ser manipulado por robôs e isto tem sido feito com bastante frequência. Mesmo uma Wikipedia pode ser editada, apesar dos controles existentes para evitar manipulações nos verbetes.
Finalmente, o Big Data é uma informação sensível. Imagine que deseja verificar o volume de pesquisa da minha universidade através do uso da rede existente lá. Se o objetivo da pesquisa é procurar saber quais as áreas que estão sendo objeto de interesse por parte dos alunos e docentes, o endereço da internet que está sendo consultado agora pode representar uma fonte de informação valiosa. Entretanto, com este tipo de informação, a pesquisa irá descobrir que muitas pessoas usam a rede para assistir um filme na Netflix, ou um jogo de futebol ou até um site pornográfico. A informação obtida pode revelar preferências sexuais e ideológicas, dados pessoais que podem constranger as pessoas. Isto explica a inacessibilidade deste tipo de informação.
50 anos da Revolução de Ball e Brown na contabilidade
In the early to mid 1960s, the finance world had a very low opinion of accounting, particularly in terms of financial statement information. The generally accepted wisdom was that such accounting was of no value in the assessment of a business’s worth, and was therefore completely unrelated to such investment matters as stock prices. It’s an attitude that seems absurd today.
The respect in which accounting is currently held is partly due to the work done by two young Australians at the University of Chicago. One was Philip Brown. The other was Ray Ball, who arrived at the university’s hallowed halls a few years after Brown.
“When I arrived the place just crackled with ideas,” Ball, who was four-and-a-half years younger than Brown, says.
“You would walk into the faculty lounge and say something and someone would immediately get up and start writing on the blackboards, trying to dissect the idea, pull it apart and play with it.
[...]
The idea that Ball and Brown challenged was the one around the value of accounting. The lowly opinion of the profession came from the fact that, at the time, there were so many different methods accountants could choose to produce various financial results. It led to the belief that number crunchers were simply employed to hoodwink investors or creditors.
This was a serious issue at the time. An academic paper written by another Australian accounting heavyweight, R.J. Chambers, concluded that from a single set of organisational transactions, the various accounting methods available meant it was possible to report 30 million different profit figures. Another problem was historical-cost accounting, which did not take inflation into account and therefore, on balance sheets, did not compare like with like.
Ball and Brown believed that accounting would never have played such a central role in business and finance for so many centuries if it truly lacked value and meaning.
They decided to run a study, which, put very simply, would find out whether and how share prices had reacted to information captured in financial statements in the past. The pair did so by crunching big data, and the data really was big. The computer (the only one at the University of Chicago) filled two rooms!
“It took up an enormous space, but the size of its memory was one two-millionth the size of my iPhone’s memory,” smiles Ball, who is now the Sidney Davidson Distinguished Service Professor of Accounting at the University of Chicago Booth School of Business.
“When one person was running a job on it, nobody else in the university could do any computing. The file of historical stock returns was on magnetic tape that took three minutes for the computer to read from one end to the other.”
The results of their study empirically demonstrated for the very first time that accounting figures were of immense value to investors. Accounting reports, such as annual reports, profit reports and profit warnings, correlated directly with shifts in stock prices.
Also, the now famous “Figure 1” graph in their published paper – “Ball and Brown (1968): An Empirical Evaluation of Accounting Income Numbers” – clearly illustrated the fact that the market anticipated profit reports, building value into a stock (or taking it away) in the lead-up to a report, as well as responding with a rise or fall in value after a report’s release.
The article was originally rejected by The Accounting Review, partly because it was all but impossible to find a referee with the knowledge to handle the submission, but also because editors felt it had “little to do with accounting”.
However, in 1968, when Nicholas Dopuch (also remembered as a transformational figure in accounting research) was appointed as editor of The Journal of Accounting Research, the study finally earned its place in history.
The result
In the pre-internet era, news didn’t spread quickly. Ball and Brown returned to Australia and got on with their lives. Academics mostly reacted to their paper with indifference. The typical financial academic, Brown says, went on believing financial statement information meant nothing. Still, in the absence of the two young Australians, their research study took on a life of its own.
As more academics cited “Ball and Brown (1968)” in their own work, people began to take notice. Eventually, those in the academic and financial realms recognised the work as a true classic.
“Overall, ‘Ball and Brown (1968)’ expressed a view of information in markets that was new to the accounting literature, and contributed to a sea change in attitudes toward financial markets, disclosure, and financial reporting,” the pair wrote in a 2014 paper called “Ball and Brown (1968): A Retrospective”, published in The Accounting Review.
“Viewed more generally, the research demonstrated that accounting is a viable area for market-based and information-economics reasoning, at a time when these areas were just being developed. It helped elevate the status of accounting research among colleagues in adjacent areas and in universities generally. We are fortunate and proud to have authored it.”
The respect in which accounting is currently held is partly due to the work done by two young Australians at the University of Chicago. One was Philip Brown. The other was Ray Ball, who arrived at the university’s hallowed halls a few years after Brown.
“When I arrived the place just crackled with ideas,” Ball, who was four-and-a-half years younger than Brown, says.
“You would walk into the faculty lounge and say something and someone would immediately get up and start writing on the blackboards, trying to dissect the idea, pull it apart and play with it.
[...]
The idea that Ball and Brown challenged was the one around the value of accounting. The lowly opinion of the profession came from the fact that, at the time, there were so many different methods accountants could choose to produce various financial results. It led to the belief that number crunchers were simply employed to hoodwink investors or creditors.
This was a serious issue at the time. An academic paper written by another Australian accounting heavyweight, R.J. Chambers, concluded that from a single set of organisational transactions, the various accounting methods available meant it was possible to report 30 million different profit figures. Another problem was historical-cost accounting, which did not take inflation into account and therefore, on balance sheets, did not compare like with like.
Ball and Brown believed that accounting would never have played such a central role in business and finance for so many centuries if it truly lacked value and meaning.
They decided to run a study, which, put very simply, would find out whether and how share prices had reacted to information captured in financial statements in the past. The pair did so by crunching big data, and the data really was big. The computer (the only one at the University of Chicago) filled two rooms!
“It took up an enormous space, but the size of its memory was one two-millionth the size of my iPhone’s memory,” smiles Ball, who is now the Sidney Davidson Distinguished Service Professor of Accounting at the University of Chicago Booth School of Business.
“When one person was running a job on it, nobody else in the university could do any computing. The file of historical stock returns was on magnetic tape that took three minutes for the computer to read from one end to the other.”
The results of their study empirically demonstrated for the very first time that accounting figures were of immense value to investors. Accounting reports, such as annual reports, profit reports and profit warnings, correlated directly with shifts in stock prices.
Also, the now famous “Figure 1” graph in their published paper – “Ball and Brown (1968): An Empirical Evaluation of Accounting Income Numbers” – clearly illustrated the fact that the market anticipated profit reports, building value into a stock (or taking it away) in the lead-up to a report, as well as responding with a rise or fall in value after a report’s release.
The article was originally rejected by The Accounting Review, partly because it was all but impossible to find a referee with the knowledge to handle the submission, but also because editors felt it had “little to do with accounting”.
However, in 1968, when Nicholas Dopuch (also remembered as a transformational figure in accounting research) was appointed as editor of The Journal of Accounting Research, the study finally earned its place in history.
The result
In the pre-internet era, news didn’t spread quickly. Ball and Brown returned to Australia and got on with their lives. Academics mostly reacted to their paper with indifference. The typical financial academic, Brown says, went on believing financial statement information meant nothing. Still, in the absence of the two young Australians, their research study took on a life of its own.
As more academics cited “Ball and Brown (1968)” in their own work, people began to take notice. Eventually, those in the academic and financial realms recognised the work as a true classic.
“Overall, ‘Ball and Brown (1968)’ expressed a view of information in markets that was new to the accounting literature, and contributed to a sea change in attitudes toward financial markets, disclosure, and financial reporting,” the pair wrote in a 2014 paper called “Ball and Brown (1968): A Retrospective”, published in The Accounting Review.
“Viewed more generally, the research demonstrated that accounting is a viable area for market-based and information-economics reasoning, at a time when these areas were just being developed. It helped elevate the status of accounting research among colleagues in adjacent areas and in universities generally. We are fortunate and proud to have authored it.”
Fonte: aqui
02 agosto 2019
Atividades do Iasb
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