Sunday, November 24, 2013

Why men should advocate gender equity - the case against the business case

A few weeks back, an article appeared on the Women in Astronomy blog by Ed Bertschinger on 'why men should advocate gender equity'. The main reason put forward was that this would ultimately benefit their departments. This argument, or variants on it, is often heard and was something I had been thinking on prior to the post appearing. I commented on Ed's post that this utilitarian argument missed the point - men should support equity because it is right, not because of some expected benefit in the future; Ed responded that his argument was indeed utilitarian, but that, while he was motivated by social justice, he was also a pragmatist.
My feeling is that utilitarian arguments, while they may have their place in making business cases (as I said in my original response), do a great disservice to the social justice movement when advanced more generally as a reason for people to support causes. They do not encourage people to act out of a desire for social justice, but for selfish reasons; they do not challenge anyone to 'check their privilege', but merely to reach some pragmatic goal of 'equity'; and they actively discourage anyone from speaking out against inequitable treatment that benefits them personally.
Yet these utilitarian arguments remain pervasive. Another example that everyone will probably have heard is that we need to build diverse groups because that leads to better decision making. But, an objector might ask, how often do we take group decisions in science? The PI system, where there is one team leader and a group of junior researchers, does not fit this model. Maybe team cohesion - which is negatively affected by diversity - is more important?
This leads to another question I touched on in my response to Ed: whether these utilitarian arguments are truly pragmatic. In academia, the employment situation is (in general) what economists refer to as 'Pareto-optimal' - any improvement in the prospects of getting a job for one person will reduce the prospects for another. This means that it makes no sense from a utilitarian prospective for a job-seeking member of a privileged group to promote the prospects of an under-privileged group.
It appears, therefore, that the utilitarian 'good of the department' argument can only be used pragmatically when dealing with those whose performance is measured by how well the department (or institute) as a whole performs - the heads of departments and the administrators. It has no pragmatic appeal to those already in permanent positions at the top of the promotion ladder, it only appeals to those seeking promotion (or tenure, where the tenure-track system is used) inasmuch as it has already been identified as a departmental priority (and even then visible support of the priority is more important than effective action), and it actually has negative appeal for post-docs, other junior researchers, and non-permanent (non-tenure track) faculty.
Fortunately, there are many people who are inspired by pro-social ideals, and these people should be encouraged. It is important (but difficult) to distinguish between those seeking affirmation for doing something they believe in, and those who are after 'cookies' or 'liberal brownie points'. The need for affirmation is human and should not be disparaged, or people may get discouraged and give up on the good they are trying to do. Those working for social justice may do so from a religious perspective, or may be secular humanists; they may have a well-developed philosophy or may be acting out of an instinctive sense of fairness; they may even believe that they are acting pragmatically 'for the good of the department' - but fundamentally they will be doing good because it is right, not because they expect to benefit from doing so.
The utilitarian argument leads to the conclusion that we should only act for a definite benefit, and only then if the cost of acting is less than the expected gain. The social justice principle, in contrast, says that we should always act, even if no benefit can be identified and even at personal cost. It is nice when doing the right thing brings a benefit, but if we are only doing it for that reason and not because it is right, we are acting selfishly, not justly.

Tuesday, November 19, 2013

Exploding the myth of e-reader battery life

It would have been interesting to have been in the room when the marketing folks revealed how they were going to spin the battery life of e-readers. Was the headline 'battery lasts for weeks, not hours' greeted with a standing ovation? Was the small print 'based on a half hour of reading per day' met with hushed reverence? Did the engineers bury their heads in their hands? (Quotes from's Kindle Paperwhite Touch page.)
Whatever the initial reception, there can be no doubt that it worked. In their comparison of e-readers and tablets, the respected technology site CNET says:
The other big advantage of e-ink readers is battery life, which is measured in weeks, not hours. Instead of using a reading app on a phone or tablet that will cut into the battery life you might need for other tasks, you can read as long as you'd like on an e-ink reader, and keep the phone ready for phone calls, email, or web browsing instead.
Hook, line, and sinker. This review is now quoted on Wikipedia as an authoritative source for the idea that e-readers have better battery life than tablets, but it is entirely based on marketing hype.
The Amazon Kindle Paperwhite claims a battery life of up to eight weeks, with wireless off and the brightness turned down. The Google Nexus 7 (2013 model) tests as having up to 9 hours of battery life in mixed-use tests at Surely there should be no contest? I decided to test the Nexus 7 under similar conditions to the Kindle to see what I would find...
The test setup was quite simple. I charged the tablet fully, turned off wireless, turned down the screen brightness to a point where I could still read comfortably, and read until the battery hit 90%. I used two epub readers for the test - Aldiko and Moon Reader+, both available for free from the Google Play Store. The OS was Android 4.3 (the 4.4 update that is supposed to improve battery life hasn't reached me yet). One mistake was that a weather app I had used earlier turned out to still be trying to check its server in the background; this was responsible for 5% of battery usage during the test period.
My first finding was that the screen dominates battery usage, taking about 85% of the power. The Nexus 7, like virtually every modern device, powers down unused parts of the CPU, so I was running on a single core at a low clock speed. The epub apps and the OS took about 10% of the power between them. Battery usage did not seem to depend significantly on which e-reader app I used.
The big shock, however, was how long the test lasted: I ended up taking the tablet to bed with me instead of the Kindle. To use up just 10% of the battery took 3.25 hours, implying a total life of 32.5 hours. Or 9 weeks, if it were marketed like an e-reader.
I was surprised. I had known that the Nexus would be a lot closer to the Kindle than the official figures implied, but that it actually had better battery life was astonishing. It may be that I got lucky - but 'up to 8 weeks' for the Kindle implies the best possible result is 8 weeks, so I don't feel I'm being unfair. Another potential problem may be that battery usage would change as the charge level dropped, but I've not noticed any such variation in general usage of the Nexus and have no reason to suspect that the battery meter isn't reporting correctly. It might also be suggested that I shouldn't have turned down the screen brightness - but I adjust the screen brightness to suit the conditions when using the Kindle, and in anything other than bright sunlight would have it on a higher setting than the one Amazon uses for their test.
In conclusion, the idea that e-readers have longer battery life than tablets is due to marketing hype and their different patterns of normal usage - comparing apples and oranges. When the Nexus 7 was used solely as an e-reader - comparing apples to apples - it actually had better battery life than the Kindle.