Archive for discrimination

your GAN is secretly an energy-based model

Posted in Books, Statistics, University life with tags , , , , , , , , , , , , , on January 5, 2021 by xi'an

As I was reading this NeurIPS 2020 paper by Che et al., and trying to make sense of it, I came across a citation to our paper Casella, Robert and Wells (2004) on a generalized accept-reject sampling scheme where the proposal changes at each simulation that sounds surprising if appreciated! But after checking this paper also appears as the first reference on the Wikipedia page for rejection sampling, which makes me wonder if many actually read it. (On the side, we mostly wrote this paper on a drive from Baltimore to Ithaca, after JSM 1999.)

“We provide more evidence that it is beneficial to sample from the energy-based model defined both by the generator and the discriminator instead of from the generator only.”

The paper seems to propose a post-processing of the generator output by a GAN, generating from the mixture of both generator and discriminator, via a (unscented) Langevin algorithm. The core idea is that, if p(.) is the true data generating process, g(.) the estimated generator and d(.) the discriminator, then

p(x) ≈ p⁰(x)∝g(x) exp(d(x))

(The approximation would be exact the discriminator optimal.) The authors work with the latent z’s, in the GAN meaning that generating pseudo-data x from g means taking a deterministic transform of z, x=G(z). When considering the above p⁰, a generation from p⁰ can be seen as accept-reject with acceptance probability proportional to exp[d{G(z)}]. (On the side, Lemma 1 is the standard validation for accept-reject sampling schemes.)

Reading this paper made me realised how much the field had evolved since my previous GAN related read. With directions like Metropolis-Hastings GANs and Wasserstein GANs. (And I noticed a “broader impact” section past the conclusion section about possible misuses with societal consequences, which is a new requirement for NeurIPS publications.)

racism, discrimination and statistics – examining the history [at the RSS]

Posted in Books, Statistics, University life with tags , , , , , on October 23, 2020 by xi'an

The Royal Statistical Society is holding an on-line round table on “Racism, discrimination and statistics – examining the history” on 30 October, at 4pm UK time. The chair is RSS President Deborah Ashby and the speakers are

  • John Aldrich – chair of the RSS History Section
  • Angela Saini – science journalist
  • Stephen Senn – Fisher Memorial Trust

voting inequalities in the US

Posted in Kids, pictures, Travel with tags , , , , , , , , , on July 8, 2020 by xi'an

“We’re the only advanced democracy that deliberately discourages people from voting.” Barack Obama

Following a poorly attended local election in France last weekend, over-interpreted by media and political analysts as usual, with poorer categories more likely to abstain, I reflected on the supplementary degree of voting inequality in the US, where active voter suppression and voting discrimination run uncontested by legislative and constitutional bodies. As it happens, even for federal elections, the election laws are state-based, voted by partisan state lawmakers and implemented by equally partisan officials.This means discriminating practices can become part of these laws, including different restrictions on acceptable forms of identification that poorer voters may be unable to purchase, restrictions on voter registration and in particular on active drives for minority registrations, discriminatory closures of voting (poll) places,  as e.g. a single voting place for 600,000 voters, meaning unreachable stations for those without transportation means and those housebound, abusive voter purges by local administrations, e.g., the Interstate Voter Registration Crosscheck System having 99% more chances to remove legitimate than illegitimate voters, lifelong felon disenfranchisement, including for citizens having completed their sentence, some places asking for on-the-spot proof of US citizenship, involving document poorer voters cannot access, mail-in voting discrimination, no worker protection for participating in the vote, which takes place during the week, grossly underfunded poll budgets, leading for instance to hour long polling queues and various mismanagement of the votes, the possibility for National Guard staffing poll stations, and the century long absurdity of gerrymandering, where something like 60 million Americans live in a place where the ruling party has received the minority of the votes in a state election. Not to mention the election by an electoral college of the president where the winner may lag by 3 million votes behind his contender… And running uncontested grossly misleading political adds

 

“the U.S. census needs a different race question”, does it?

Posted in Books, Statistics, Travel with tags , , , , , , , on March 31, 2020 by xi'an

“The stated aim — at least for the last half century — [of the census race question] is to help policy makers and demographers assess whether members of different racial groups have equal access to housing, education, employment and other services, as mandated by law.”

A fairly interesting tribune in Science News on the U.S. census race question and the feature that people often self-identify with a category with “doesn’t always match the box someone else might have checked for them”. The discussion focus on failing to protect discriminated groups because people from said discriminated groups do not identify as members of said discriminated groups. Or, because of a genetic ancestry test like 23andme, people from non-discriminated groups do identify as members of a particular discriminated group, e.g., native American Indians. And while there is a separate question on whether or not the respondant is of Hispanic, Latino or Spanish origin, a third of those answering in the affirmative tick the “other race” box in the census. While the sociologist whose work inspired this article calls for different questions in the census, towards a better reflection of actual discrimination, nowhere is the notion of “race” defined or explicited in this paper. Which may be related to the fact that there is no scientifically accepted such definition, as discussed in this UN report. Except all of us belonging to the Homo sapiens sapiens subspecies and descending from common ancestors in Africa.

I thus wonder at the relevance at keeping such a confusing entry in a census: in several European countries including France, it is actually illegal to collect statistics about the race, ethnicity, religion or ancestry. Given the above confusion in the US census and no clear solution to redress the observed biases, discrimination should be fought on sounder bases…

Australian theocracy

Posted in Kids, pictures, Travel with tags , , , , on December 25, 2019 by xi'an

Examples from The Guardian at which discrimination based on religious arguments should become legal in Australia:

  • A doctor may tell a transgender patient of their religious belief that God made men and women in his image and that gender is therefore binary (EM)

  • A single mother who, when dropping her child off at daycare, may be told by a worker that she is sinful for denying her child a father (Public Interest Advocacy Centre)

  • A woman may be told by a manager that women should submit to their husbands or that women should not be employed outside the home (PIAC)

  • A student with disability may be told by a teacher their disability is a trial imposed by God (PIAC)

  • A person of a minority faith may be told by a retail assistant from another religion that they are a “heathen destined for eternal damnation” (PIAC).

  • A Catholic doctor refusing to provide contraception to all patients (EM) or to prescribe hormone treatment for gender transition (Equality Australia, Just Equal, LGBTI Health Alliance)

  • A Catholic nurse who refused to participate in abortion procedures (EM) or to provide the morning-after pill to a woman admitted to hospital after a sexual assault (Equality Australia)

  • A pharmacist refusing to provide the pill to women for contraceptive use (EM), or hormone treatment (Public Interest Advocacy Centre, LGBTI Health Alliance)

  • A doctor could refuse to prescribe post-exposure prophylaxis (PEP) within the required 72-hour window to a patient whose condom broke during a sexual encounter on the basis of religious beliefs that forbid sexual activity outside of marriage (Equality Australia)

  • A psychiatrist could say to a woman with depression that “she should be looking forward to the kingdom of heaven”. (Equality Australia)

  • A Jewish school may require that its staff and students be Jewish and accordingly refuse to hire or admit someone because they were not Jewish (EM)

  • A student attends the same religious school through their primary and secondary education. At 16 they lose faith in the religion of the school and tell a teacher that they are now agnostic. The school would be able to expel, suspend or otherwise punish, for example, give detention to the student (PIAC)

  • A homeowner seeking a tenant for their spare room may require that the tenant be of the same religious belief or activity as the homeowner (EM).