Science does not rely on authority as an indicator of truth.

Ben Goldacre: Battling bad science


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It is worth reiterating that contrary to popular depictions of science, science does not rely on authority as an indicator of truth.

The video reminds me of an xkcd comic showing the problem with using statistical significance if the studies showing no effect are unreported.

Significant
In this analogy, the study showing a link between green jelly beans and acne has only a 5% probability (or less) of being a coincidence (p < 0.05). This would be convincing evidence that there is a link between green jelly beans and acne, except all the 19 studies showing no link between non-green jelly beans and acne were unreported and discarded. If all the study results were reported, then it would suggest that the result of the green-jelly-bean study is indeed a coincidence: 1/20 = 5%.

Scientific studies in real life can be even worse. Companies, and even university researchers, are not obligated to publish studies in which the results show no effect (studies with “null results”). This means that researchers can run the hypothetical green-jelly-bean study 20 times until they get the result that they want, by coincidence. What normally happens does not involve ill intent, but has the same effect. The hypothetical green-jelly-bean study is run independently by 20 different research teams (who can be separated by time), who are unaware of each other, because studies with negative results are not published. Only the group with the positive result publishes its results, but the result is actually a coincidence. See the concept of publication bias at Wikipedia.
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Carl Sagan on why his science organization should stop excluding women (1981)

If membership is restricted to men, the loss will be ours:

Early-1981, following IBM’s withdrawal of support due to the organisation’s continued exclusion of women within its ranks, renowned astronomer Carl Sagan sent the following impassioned letter to each and every fellow member of The Explorers Club — an international society dedicated to scientific exploration since its inception in 1904 — and argued beautifully for a change of policy.

Later that year, The Explorers Club welcomed its first female members.

Carl Sagan’s letter:

Dear Fellow Member of The Explorers Club:
Thank you for the opportunity to write to you about the admission of women to The Explorers Club. The human zest for exploration and discovery is the hallmark of our species and one of the secrets of our success. It is a tradition that goes back much further than the 76 proud years in which The Explorers Club has been in existence. When our organization was formed in 1905, men were preventing women from voting and from pursuing many occupations for which they are clearly suited. In the popular mind, exploration was not what women did. Even so, women had played a significant but unheralded role in the history of exploration — in Africa in the Nineteenth Century, for example. Similarly, Lewis and Clark were covered with glory, but Sacajewea, who guided them every inch of the way, was strangely forgotten. All institutions reflect the prejudices and conventions of their times, and when it was founded The Explorers Club necessarily reflected the attitudes of 1905.
Traditions are important. They provide continuity with our past. But it is up to us to decide which traditions are essential to The Explorers Club and which are accidents of the epoch in which it was institutionalized. Times have changed since 1905. It is very clear that a foolish rigidity can destroy otherwise worthwhile institutions; they are then replaced by other organizations more in tune with the times. IBM’s recent withdrawal of corporate support for The Explorers Club because of our “exclusionary policy toward women” should be pondered carefully by every member. Many other former supporters may follow suit.
Today women are making extraordinary contributions in areas of fundamental interest to our organization. There are several women astronauts. The earliest footprints — 3.6 million years old — made by a member of the human family have been found in a volcanic ash flow in Tanzania by Mary Leakey. Trailblazing studies of the behavior of primates in the wild have been performed by dozens of young women, each spending years with a different primate species. Jane Goodall’s studies of the chimpanzee are the best known of the investigations which illuminate human origins. The undersea depth record is held by Sylvia Earle. The solar wind was first measured in situ by Marcia Neugebauer, using the Mariner 2 spacecraft. The first active volcanos beyond the Earth were discovered on the Jovian moon Io by Linda Morabito, using the Voyager 1 spacecraft. These examples of modern exploration and discovery could be multiplied a hundredfold. They are of true historical significance. If membership in The Explorers Club is restricted to men, the loss will be ours; we will only be depriving ourselves.
The supposed parallelism between our situation and those of other organizations seems to me strained. The Bohemian Club is a resort; The Explorers Club is not. The Boy Scouts and Girl Scouts are for children. Their membership derives almost exclusively from adolescent and pre-adolescent youngsters, who have not yet fully accomodated to the opposite sex. But we presumably are adults, with a special responsibility for interacting with all humans on this planet.
I do not believe that the primary function of our organization is to promote male bonding or to serve as a social club — although there is certain room for both. I believe that the fundamental dedication of the club is that stated on the masthead of every issue of The Explorers Club Newsletter: “To the conquest of the unknown and the advancement of knowledge.” If this is our purpose, then admission should be open to all qualified members of the human species.
Cordially,

(Signed)

Carl Sagan

Misogynist activist at the University of Waterloo hates scientist Marie Curie and women.

In The Fourteen Not Forgotten and Sexist Posters at Waterloo, Christine Cheng discusses a misogynist activist at the University of Waterloo who put up fourteen posters last month (February 2011) vilifying scientist Marie Curie and women in general. (Her post is also cross-posted at the Geek Feminism Blog.)

A photograph of Marie Curie has an image of a mushroom cloud next to it. It is titled 'The Truth'. The caption at the bottom of the poster says, ''The brightest Woman this Earth ever created was Marie Curie. The Mother of the Nuclear Bomb. You tell me if the plan of Women leading Men is still a good idea !'

The incident reminds many of us of the École Polytechnique Massacre. Both the University of Waterloo and l’École Polytechnique de Montréal focus on STEM (Science, Technology, Math, and Engineering) fields, and female students are a minority. Both schools are located in Canada. Both misogynists appear to be angry that women are attending university and are being educated in male-dominated fields.

The Marie-Curie-hating misogynist at Waterloo has also sent out a misogynist e-mail pretending to be the university’s president, and has created a Facebook page with similar misogynist rantings. The university’s Women’s Centre and LGBT student centre have closed due to safety concerns.

A male undergraduate at the University of Waterloo made this ridiculous—yet typical male-privileged—comment before taking down his post:

Yes, it is wrong, yes, it is inappropriate, but get a life if you are going to fuss and cry over stupid shit like this. Because if you do, you must be living in a sheltered bubble.

A commenter at hook & eye named bakka111 responds to this reaction:

The “Sheltered bubble” comment from Bill’s portfolio is particularly ironic. Just who lives in a sheltered bubble? Those who fear the messages because they have experienced the mundane-threats a patriarchal culture issues to women, or those who have never experienced such threats. Oh the irony.


Further Reading:

Across the calculus sections, women outperformed men on grades.

Several recent studies have suggested that the gender gap in STEM fields is caused not by bias, but simply by different choices made by men and women. What the new research shows, Dasgupta said, is choice isn’t as simple as people think. “People assume that these choices are free choices, based on talent and interest and motivation,” Dasgupta said. “But these data suggest that the meaning of choices, of what it means to choose math or science, is more complicated. Even talented people may not choose math or science not because they don’t like it or are not good at it, but because they feel that they don’t belong.”

Inoculation Against Stereotype by Scott Jaschik (Inside Higher Ed)

There is a common belief among some computer geek communities that women are underrepresented in STEM because we just don’t like it, and so we should celebrate differences instead of making women “miserable” by “forcing” us into careers we “don’t like”. This study would debunk that myth, if only most men in tech who discuss the topic of women in tech actually did some research on it, instead of leaving comments that make male geeks feel good about themselves and rationalize the gender imbalance in “their” field.

For other male geeks who insist that there are hard-wired brain differences in men and women, and argue that women’s brains are hard-wired against understanding math and science as well as men (instead of hard-wired against enjoying math and science), this part of the article should be emphasized:

Skeptics might wonder if some of the [gender] differences [in engagement] among students relate to how well the students know the material. The researchers checked for that and found that, across sections, women outperformed men on grades. So the data point to women losing confidence with male instructors — even if female students know the material as well as or better than their male counterparts.

Link: Inoculation Against Stereotype (Inside Higher Ed)

Myths about Girls, Math, and Science

Top 5 Myths About Girls, Math and Science (LiveScience 2007):

Myth 1: From the time they start school, most girls are less interested in science than boys are.

Reality: In elementary school about as many girls as boys have positive attitudes toward science. A recent study of fourth graders showed that 66 percent of girls and 68 percent of boys reported liking science. But something else starts happening in elementary school. By second grade, when students (both boys and girls) are asked to draw a scientist, most portray a white male in a lab coat. Any woman scientist they draw looks severe and not very happy. The persistence of the stereotypes start to turn girls off, and by eighth grade, boys are twice as interested in STEM (science, technology, engineering, math) careers as girls are. The female attrition continues throughout high school, college and even the work force. Women with STEM higher education degrees are twice as likely to leave a scientific or engineering job as men with comparable STEM degrees.

[…]

Myth 3: Science and math teachers are no longer biased toward their male students.

Reality: In fact, biases are persistent, and teachers often interact more with boys than with girls in science and math. A teacher will often help a boy do an experiment by explaining how to do it, while when a girl asks for assistance the teacher will often simply do the experiment, leaving the girl to watch rather than do. Research shows that when teachers are deliberate about taking steps to involve the female students, everyone winds up benefiting. This may mean making sure everyone in the class is called on over the course of a particular lesson, or asking a question and waiting 10 seconds before calling on anyone. Good math and science teachers also recognize that when instruction is inquiry-based and hands-on, and students engage in problem solving as cooperative teams, both boys and girls are motivated to pursue STEM activities, education and careers.


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