Tuesday, January 30, 2018

O fim da liberdade de manifestação na América Latina?

Under a cloud: Tear gas, violence and new laws are all being used to frighten Latin American protesters into giving up, por Duncan Tucker:

IT’S NOT JUST the clouds of tear gas, the ping of rubber bullets or the prospect of arrest under draconian new laws that Latin Americans have to consider when they take to the streets.

With freedom of expression increasingly under threat, demonstrating in Caracas’ packed plazas, Rio de Janeiro’s hillside slums or Mexico’s rural towns can mean risking one’s life at the hands of oppressive, and largely unrestrained, security forces. (...)

These trends are particularly pronounced in Venezuela, Brazil and Mexico – three of the region’s most politically and economically influential countries – where rampant violence, corruption and inequality are set to shape their respective elections in 2018.

As opposition to Venezuela’s socialist president, Nicolás Maduro, has hardened this year, so too has the state response. Faced with mounting public anger over severe inflation, insecurity, political repression and desperate shortages of food and medicine, Maduro’s government has passed several laws to criminalise protesters.

Recent legislation has limited the movement of protesters and justified force against those who block traffic or hold demonstrations without prior permission. Other new laws allow armed forces to establish order during demonstrations, even permitting use of deadly force if soldiers feel at risk. (...)

Brazil has recently experienced major protests over government corruption and the handling of global sporting events. The right-leaning Michel Temer administration has responded aggressively to the protests, with security forces using truncheons, tear gas, stun grenades and water cannons against demonstrators and journalists.

The government has defended the deployment of soldiers to “restore order” during demonstrations, but the CELS report notes that security forces are inadequately trained for this work. Military police are often accused of extrajudicial executions and unnecessary use of force, but rarely face charges.
Activists have denounced police surveillance of social networks and the phone tapping of protesters, who risk conspiracy charges over the mere possibility that they could commit violent acts. Other common charges include contempt, threat, resistance or disobedience for resisting or verbally denouncing violent or illegal police behaviour. (...)

In Mexico, the centrist Enrique Peña Nieto administration has taken significant flak over corruption scandals, a stagnant economy, record levels of drug-related violence and the disappearance of 43 student activists in 2014. The state has sought to limit dissent through stringent regulations and faces accusations of using violent intimidation tactics.

Mexican authorities have passed or submitted at least 17 local and federal initiatives to regulate demonstrations in the past three years, including legislation that gives authorities broad powers to break up protests, restrict the movement of participants and demand advance notice of demonstrations.

In parts of Mexico, the lines between the state and organised crime are so blurred that journalists and activists are at almost equal risk from corrupt security forces and drug cartels. In extreme cases, demonstrators have suffered torture, sexual violence, forced disappearance and extrajudicial execution.

Thursday, January 25, 2018

As leis contra "discurso de ódio" na prática

In Europe, Hate Speech Laws are Often Used to Suppress and Punish Left-Wing Viewpoints, por Glenn Greenwald:

MANY AMERICANS WHO long for Europe’s hate speech restrictions assume that those laws are used to outlaw and punish expression of the bigoted ideas they most hate: racism, homophobia, Islamophobia, misogyny. Often, such laws are used that way. There are numerous cases in western Europe and Canada of far-right extremists being arrested, fined, or even jailed for publicly spouting that type of overt bigotry.

But hate speech restrictions are used in those countries to suppress, outlaw, and punish more than far-right bigotry. Those laws have frequently been used to constrain and sanction a wide range of political views that many left-wing censorship advocates would never dream could be deemed “hateful,” and even against opinions which many of them likely share. (...)

As we reported at the time, France’s use of hate speech laws to outlaw activism against Israeli policy — on the grounds that it constitutes “anti-Semitism” and hatred against people for their national origin — is part of a worldwide trend. In May of last year, Canada’s then-conservative government threatened to use the nation’s rigorous hate speech laws to prosecute Israel boycott advocates on the ground that such activism is “the new face of anti-Semitism.” (...)

There can be little question that if the power to ban “hate speech” were vested in the hands of U.S. officials or courts, the same thing would happen. It is a virtually unquestioned bipartisan consensus that advocating a boycott of Israel constitutes hatred and anti-Semitism. In her 2016 AIPAC speech, Hillary Clinton cited the boycott movement as evidence that “anti-Semitism is on the rise across the world.” (...)

Does anyone doubt that high on the list of “hate speech” for many U.S. officials, judges, and functionaries would be groups, such as Black Lives Matter and antifa, far-left groups that fight against white supremacists? Some GOP-controlled state legislatures are already arguing that BLM should be officially classified as a “hate group.” Beyond what many officials say is the group’s hatred for police officers, they also “point to its platform that accuses Israel of carrying out genocide against the Palestinians.”

In the UK, “hate speech” has come to include anyone expressing virulent criticism of UK soldiers fighting in war. In 2012, a British Muslim teenager, Azhar Ahmed, was arrested for committing a “racially aggravated public order offence.” His crime? After British soldiers were killed in Afghanistan, he cited on his Facebook page the countless innocent Afghans killed by British soldiers and wrote: “All soldiers should DIE & go to HELL! THE LOWLIFE F*****N SCUM! gotta problem go cry at your soldiers grave & wish him hell because that where he is going.” (...)

This is how hate speech laws are used in virtually every country in which they exist: not only to punish the types of right-wing bigotry that many advocates believe will be suppressed, but also a wide range of views that many on the left believe should be permissible, if not outright accepted. Of course that’s true: Ultimately, what constitutes “hate speech” will be decided by majorities, which means that it is minority views that are vulnerable to suppression.

In 2010, a militant atheist was given a six-month suspended sentence for leaving anti-Christian and anti-Islam fliers in a religious room of the Liverpool airport; according to the BBC, “jurors found him guilty of causing religiously aggravated intentional harassment.” In Singapore, “hate speech” laws are routinely used to punish human rights activists who criticize Christianity, or Muslims who have defended or promoted sermons from imams deemed too critical of other religions. Cases in Turkey are common where citizens have been prosecuted under hate speech laws for criticizing government officials or the military. Radical imams are prosecuted in Europe if they are too strident in their support for sharia law or their defense of violence against western aggression. (...)

Monday, January 22, 2018

Hitler e Trump

If authoritarianism is looming in the US, how come Donald Trump looks so weak?, por Corey Robin (The Guardian, via Crooked Timber):

On 19 January 1934, the 354th day of Hitler’s reign, the Nazi regime closed the Kemna concentration camp, where anywhere from 2,500 to 5,000 political prisoners – most of them Communists, Socialists, and trade unionists – had been held and tortured (the press spoke obliquely of “enhanced interrogations”) for months. People could hear the prisoners’ screams from almost a half-mile away. The prisoners were moved to other concentration camps.

On 9 January 2018, the 354th day of Trump’s reign, the president was anxiously monitoring news of a best-selling book – filled with leaks from his own top advisers, testifying to the addled state of his mind and rule – hoping against hope to stop any and all discussion of his fitness for office.

Trump’s lawyers had already tried to force the book’s publisher and author to cease publication, issue a retraction, and apologize. Their reply? We “do not intend to cease publication, no such retraction will occur, and no apology is warranted”.

Friday, January 19, 2018

E porque é que os bons alunos haveriam de ir para professores?

No Observador estão preocupados por os bons alunos não quererem ser professores; mas isso é um problema porquê?

Para começar, nem estou certo que a forma como o Alexandre Homem Cristo vê a coisa seja totalmente correta - comparar as notas de entrada dos cursos de Ciências da Educação com os outros cursos; confesso que não sei como é atualmente, mas no meu tempo quem dava aulas não eram só os licenciados em Ciências da Educação, eram licenciados nas áreas disciplinares respetivas ou associadas (historiadores a dar aulas de História, engenheiros a dar aulas de Matemática ou Trabalhos Oficinais, contabilistas a dar aulas de Contabilidade, etc.; até eu - economista - fui em tempos professor de Matemática e Administração, Serviços e Comércio); assumir que só os licenciados em Ciências da Educação é que vão dar aulas parece-me logo um erro que distorce todas as conclusões.

Depois, esquece o problema do custo de oportunidade - ensinar (e ensinar alunos do primário e secundário) será mesmo a melhor coisa para os bons alunos fazerem? Pensemos nas alternativas - podem trabalhar num laboratório a desenvolverem uma energia limpa sem problemas de intermitência ou a cura para a SIDA; podem fazer operações para tratar doenças raríssimas e super-complexas; se os quiserem mesmo pôr a dar aulas, podem ser professores universitários (eventualmente a fazer investigação nas horas vagas). Todas essas coisas parecem-me ter maior complexidade intelectual do que ensinar alunos do secundário ou do primário - afinal, quase por definição o que se ensina no primário e no secundário é matéria de um nível mais elementar do que se ensina na universidade ou do que é aplicado na maior parte das profissões que se vão exercer com um curso universitário (isto assumindo que se aprende mesmo coisas necessárias para a profissão e que o curso não é apenas "sinal"). Além disso, o ensino é uma coisa em que, por regra, não se deve inventar - um professor de liceu deve ensinar aos seus alunos o programa escolar, não as suas teorias que ele próprio desenvolveu, e também imagino que não haja muitas situações em que seja preciso descobrir soluções para problemas de elevada complexidade intelectual (o professor não vai ele próprio descobrir a fórmula resolvente para as equações de segundo grau - isso já foi feito por um indiano no século VII; vai é explicar qual é e como se chega a ela) - suponho que os problemas complexos que os professores tenham que resolver seja sobretudo lidar com alunos complicados, e que a solução para isso não passe normalmente por grandes conhecimentos técnicos ou capacidade intelectual, mas mais, ou por firmeza ou por empatia (talvez me esteja a deixar levar pelos estereótipos, mas suspeito que nem "firmeza" nem "empatia" sejam qualidades muito abundantes entre os bons alunos, e que entre eles predomine mais o tipo "eu quero é que não me chateiem" em detrimento tantos dos tipos "durão" como "simpático").

Finalmente, será que os bons alunos (além de provavelmente terem coisas melhores para fazer) serão sequer bons professores para alunos do secundário (e ainda mais do primário)? Ao verem um aluno com dificuldade em perceber uma coisa que, nessa idade, eles perceberam quase intuitivamente na primeira aula em que isso se falou, será que têm realmente capacidade para o ajudar, ou será que começam logo a pensar que os alunos precisam de um professor do ensino especial para os acompanhar? E saberão estruturar e planear uma aula, sem poderem confiar na introspeção (isto, sem poderem pensar "eu aprenderia facilmente se um professor me desse a aula desta maneira?", já que eles aprenderiam facilmente de qualquer maneira)? E se (como é provável) fossem daqueles alunos que gostavam de estudar (e que se calhar no 10º já andavam nas horas vagas a ler matéria do 12º), saberão perceber as motivações dos alunos (provavelmente a maioria) que acham estudar uma seca, necessária para ter boas notas e passar de ano, ou facilmente cairão na atitude "mas estudar é divertido; se vocês não acham isso divertido e só estudam por obrigação, deve haver algum problema"?

Há um contra-argumento que pode ser feito a todo este meu post - é que em larga medida estou a misturar os conceitos de "bons alunos" e "alunos mais inteligentes"; afinal, o que refiro aqui (a vocação para tarefas de elevada complexidade intelectual, o perceber tudo na primeira aula...) serão sobretudo características associadas a inteligência; mas na prática suspeito que as categorias "melhores alunos" e "alunos mais inteligentes" têm uma elevada sobreposição (acho que o aluno-inteligente-com-más-notas-porque-não-se-adapta-à-instituição-escolar é mais um cliché romântico que serve para tema de filmes e livros do que algo que seja mesmo frequente na vida real).

Um aparte final - aquelas coisas que há uns anos era moda criticar no chamado "eduquês", nomeadamente as ideias de que os alunos devem descobrir as coisas por eles (em vez de ser o professor a dizer-lhes) e de que estudar deve ser divertido parecem-me exatamente o que ocorreria num sistema educativo tomando os bons alunos (que por norma aprendem bem quase sozinhos e gostam de estudar) como modelo em vez de como anormalidades estatísticas; será um indício de que (por mais baixas que sejam as notas de entrada a Ciências da Educação) os bons alunos estejam sobre-representados entre os teóricos da educação (algo bastante provável, pelo simples facto que os bons alunos tendem a estar sobre-representados entre os teóricos de seja o que for)?

Friday, January 12, 2018

Diferenças salariais por sexo e áreas académicas

Gender pay gap persists (Nature):

Pay disparities between female and male PhD holders in the United States exist across almost all fields of science and engineering, according to a report from the US National Science Foundation (NSF).The report examines annual salaries for those who earned their doctorate in 2016 and had confirmed permanent employment in the life sciences, physical sciences, mathematics and computer sciences, psychology and social sciences, or engineering. (...) In biomedical and biological sciences, women earned $67,500 to men’s $77,000; in geosciences, atmospheric and ocean sciences, the figures were $65,500 for women and $71,000 for men; in physics and astronomy, women earned $89,000 to men’s $100,000; and in engineering, women earned $92,000 to their male counterparts’ $100,000. Women had lower salaries in all fields of social sciences, including psychology and economics. In health sciences, women and men disclosed equal salaries of $80,000. The NSF report did not indicate whether the salaries reported were within or outside academia.
Claro que se pode argumentar que, mesmo na mesma área de doutoramento, as diferenças salariais entre homens e mulheres podem ser derivadas de escolherem sub-áreas diferentes, ou usarem a mesma formação para exercerem profissões diferentes, ou... Mas então o argumento "não há discriminação salarial entre homens e mulheres - as mulheres ganham em média menos porque escolhem carreiras e profissões diferentes" começa a tornar-se muito uma proposição não-falsificável: afinal, qualquer categoria estatística pode sempre ser decomposta em subcategorias mais refinadas, logo perante qualquer estatística que demonstre as mulheres a ganharem menos que os homens em trabalhos aparentemente com as mesmas características, pode-se sempre responder que a estatística não é suficientemente granular para detetar diferenças subtis nas escolhas profissionais de homens e mulheres, tornando a teoria das "diferentes escolhas" impossível de sujeitar a contraprova.

Oprah Winfrey, a "Trump Democrata"?

Oprah Winfrey Helped Create Our American Fantasyland:

“Who would be, and could there be,” I asked Harris, “a Trump of the left that people on the left would, against their better judgment say ‘She’s a kook, and she’s terrible in this way, but she believes in socialized medicine, and this, and that—I’m going with her.’ To what degree and under what circumstances could that happen? It’s hard to imagine the equivalent, but I’m willing to accept that we might have to make those choices eventually.”

Such as who, Harris asked. Well, I replied, “people talk very seriously about Oprah Winfrey being a potential Democratic nominee for president. Is that my Trump moment, [like] what honest Republicans had to do with Donald Trump, and decide ‘No, I can’t abide this’ and became Never Trumpers? Would I be a Never Oprah person? That will be a test for me.”

Tuesday, January 09, 2018

O marxismo, o leninismo e o desaparecimento do Estado

Um clássico dos anos 20-30: Marxism and state communism. The withering away of the state[pdf], de Jan Appel, um texto publicado em 1932 pelo Grupo de Comunistas Internacionais holandês, adaptando uma versão anterior publicada em 1927 por uma das facções do KAPD - Partido Comunista Operário da Alemanha (o KAPD foi uma cisão radical do Partido Comunista da Alemanha e foi o alvo principal do livro de Lenine "O Esquerdismo, Doença Infantil do Comunismo").

Tuesday, January 02, 2018

Em defesa do "agente racional"

Why use rational choice models?, por "Upholding Economics":

A particular focus of criticism of mainstream economics is the use of rational choice in many orthodox models. Some critics are so extreme as to claim the use of rational choice should invalidate a model a priori. In reality there are many sensible reasons rational choice was and is still used commonly in economics:

Many results in behavioural economics come from small scale experiments in the form of simple games or challenges a small group of test subjects, often students, take part in. Some critics have challenged the external validity of these experiments and their application to the situations economists usually study, which might include seasoned entrepreneurs rather than nervous test participants unfamiliar to the ‘game’. Richard McKenzie emphasizes this point on his work defending the use of rationality. For instance, Richard McKenzie challenges the work of Kahneman for assuming that people favouring a ‘sure thing’ (option A: $800) over a gamble (option B: 85% chance of $1000, 15% chance of nothing) contradicts rational choice , he writes:
What the behavioralists miss is that variance in outcomes is also consequential in assessing options. Option A has no variance; Option B has a substantial variance, with the outcome ranging from zero to $1,000. Hence, for many choosers, Option A can be more valuable than Option B. Indeed, if expected value were all that mattered, people would never buy insurance. Is the purchase of insurance irrational?”
He goes on to demonstrate how framing choice problems like these in a more relevant entrepreneurial/investment setting, with more realistic outcomes and pay-offs, allowing for repeats of the test to account for learning, and ensuring the students of a personal/financial stake in the choice they make causes the behaviour of the students to converge towards rational choice as predicted by conventional theory. (...)

This of course corroborates previous studies that find experience is both a ‘catalyst’ for rationality and a ‘filter’ of irrationality, where aggregated market outcomes “quickly converge to neoclassical predictions.” To summarise, the results showing irrationality from first generation of economic experiments, often involving students in very limited scenarios with no personal stake, are not necessarily applicable to real world markets and scenarios — while there is strong evidence that real world market experience causes individuals to converge towards rational choice. (...)

One alternative to using rational choice is to explicitly model irregularities and biases as if they are a consistent aspect of behaviour which can be used to make predictions. There is a challenge with this approach however: self awareness.

Many studies have shown that anomalies (divergences from what an efficient ‘rational’ market would produce) in asset pricing behaviour soon disappear once papers are published on their existence. This strongly suggests that behavioural irregularities in relevant economic scenarios cannot be relied upon to be persistent, and because of this may not be suitable for use in long term predictive models.
Uma nota especial acerca da preferência por um resultado certo a um jogo com valor esperado superior - se os comportamentalistas usam esse exemplo para dizer que os agentes não são racionais, então isso não tem ponta onde se lhe pegue; esse é exatamente o resultado previsto pelo modelo do agente racional (aversão ao risco). Fariam mais sentido se usassem o exemplo oposto (como, aliás, de certo modo o João Vasco parece-me fazer aqui): de que muitas vezes as pessoas preferem resultados incertos a um valor certo, mesmo quando o resultado esperado é igual ou até inferior (de qualquer maneira, eu suponho que mesmo isso poderá ser enquadrado no modelo do agente racional - quase toda a gente que faz o totoloto sabe que em média perde-se mais do que ganha, logo suspeito que não é bem uma questão de "irracionalidade" mas de preferências mais complexas do que os modelos tradicionais postulam; pode ser que ainda faça um post sobre isso).