Too many university students?

Last night on BBC Radio 4 there was a programme about whether or not the UK has too many university students. I don’t remember quite who was on the panel, but it included Sally Hunt from the University and College Union (UCU) and the vice-Chancellor of the University of Buckingham, the UK’s only private university.

I found it fairly interesting, although my 5 year old son had decided to tidy the kitchen and kept interrupting me to ask for help, so I didn’t hear as much as I would have liked. The vice-Chancellor of the University of Buckingham kept promoting – rather predictably – the idea that there should be more of a free market approach to Universities in the UK. I don’t really agree with this, but since I’m trying to keep this post shorter than normal, I won’t go into this here.

What I did generally agree with is that the real issue is not whether or not there are too many students in the UK, but whether or not they are getting an appropriate University education. One of the main views on the programme seemed to be that not enough students were taking science degrees. This may well be true, but the problem in my view is subtler. It seems to me that UK universities have not structured their degrees to be appropriate to the current student intake. In most science degrees it appears that students are assumed to be doing a degree that will ultimately allow them to basically be professional scientists (i.e., most students start off doing Honours degrees or Masters degrees and a Bachelor’s degree is really a failed Honours degree).

It would seem much more reasonable – in my view – to have more granularity in the system, allowing students to graduate at various stages with various different degrees. This isn’t meant to penalise any students, but simply to be more honest about different students’s abilities and skills and to then design the degree structure appropriately. This would optimise the amount of time students spend at university and also allow employers to have a much better idea of potential employees’ actual strengths and skills.


Global warming and the planet Venus

Global warming, as many know, can be a fairly contentious subject with some believing it’s not happening at all, others believing that it is but is not a consequence of human activity, and the rest believing it is indeed a consequence of human activity. Personally, I believe that the planet is warming and that it is a direct consequence of what we are doing. The main reason that I believe this is that although the carbon dioxide (CO2) concentration in the atmosphere has varied quite a lot over the last 400000 years, until about 1800 it had never been higher than 300 parts per million per volume (ppmv). It is now 385 ppmv. This rise in CO2 concentration also correlates with a rise in average temperature with, importantly, the rise in CO2 leading the rise in temperature.

Whatever anyone believes, I think it would be useful for people to have some understanding of the planet Venus. First, however, I should talk about planets in general, and the Earth in particular. It is fairly straightforward to show that the average temperature of a planet, in Kelvin (K), in the Solar System should be Tavg = 279 (1 – A)1/4rp-1/2, where rp is the distance of the planet from the Sun in Astronomical Units (AU – the distance of the Earth from the Sun), and A is the fraction of the incident radiation that is reflected and not involved in heating the planet.

For the Earth, rp = 1 and A = 0.29 (i.e., the Earth reflects 29 % of the incident radiation). The average temperature of the Earth should therefore be 256 K. The conversion from Kelvin to oC is 273 K = 0oC, so the average temperature of the Earth should be about -16oC. This clearly isn’t the case and in fact, the average temperature of the Earth is more like +15oC. Why is this? The Earth has an atmosphere that contains various molecules, in particular CO2 and water vapour. The radiation from the Sun is mainly in the optical, most of which passes easily through the atmosphere to be absorbed by the planet’s surface. The Earth, however, is much cooler than the Sun and so reemits radiation at longer wavelengths – mainly in the infrared. The atmosphere is not particularly transparent at these wavelengths, trapping them and causing the Earth to heat up. As the Earth gets hotter, the radiation it reemits moves to shorter and shorter wavelengths, allowing more and more energy to escape back into space. Eventually the Earth reaches a temperature where as much radiant energy escapes back into space as is absorbed from the Sun. The Earth has then reached it’s equilibrium temperature which, fortunately for us, produces an average temperature of 15oC. This is a form of greenhouse warning that is clearly beneficial to us.

Now, what about Venus. Venus is a planet that is very similar in size to the Earth and probably formed at about the same time as the Earth. It is quite likely that at some point in the distant past it may have had an atmosphere similar to the Earth’s. If we assume that it also would have reflected about 29% of the incident radiation, and knowing that for Venus rp = 0.723, then we would expect it’s average temperature to be about 301 K or 28oC. As with the Earth, global warming would cause Venus to heat up to a higher average temperature, but one might naively expect this to have less of an effect than on the Earth since Venus might already be hot enough to be reemiting radiation at a wavelength for which the atmosphere is reasonably transparent.

So, what is Venus’s actual average temperature. Today Venus has an average temperature of 480oC, more than 10 times hotter than we would expect based on the above calculation. The reason is that to prevent greenhouse warming, greenhouse gases like CO2 and water vapour need to be kept out of the atmosphere. On Earth, water is mainly liquid (oceans) and most of the CO2 has dissolved in this liquid water ultimately forming carbonate rocks. Because Venus started with a higher average temperature than the Earth, there would be more water vapour in the atmosphere and less liquid water. Since water vapour is also a greenhouse gas this would actually act to also cause Venus to heat up adding more water vapour into the atmosphere. The lack of liquid water also means that more of the CO2 would be in the atmosphere (rather than in the form of carbonate rocks) also causing more greenhouse warming. In the case of Venus this lead to a runaway process in which more and more water vapour and CO2 was added to the atmosphere causing the planet to heat up until it eventually reaches it’s current equilibrium temperature of 480oC. The water vapour would also be dissociated by UV photons allowing the constituents elements (hydrogen and oxygen) to escape into space. Ultimately Venus is a planet with almost no (if any) water and an atmosphere that is primarily composed of CO2.

Is this relevant to the Earth and to us. in some sense no, because what happened on Venus was almost certainly natural and occurred because Venus was closer to the Sun and hence had an initially higher average temperature. However, it is clear that it has undergone a runaway greenhouse process that increased it’s temperature from a value where liquid water should be able to exist to one where there is no water at all and no life could possibly survive. It also seems that an Earth-like planet with an average temperature of 30 – 40oC could easily undergo this process. Although the Earth’s average temperature is somewhat lower than this, it’s not quite as far away as we might like. We also don’t really know at what temperature this runaway process actually starts. Currently it is predicted that the Earth’s average temperature will rise by more than 1o C per century. If this continues, this means it will take only a thousand years or so to reach a temperature at which the runaway greenhouse process should start. However, whatever anyone actually believes is happening at the moment, the fact that the runaway greenhouse process has actually happened on a planet that initially was not significantly different to our own should at least, in my view, give us pause for thought.

The Gini coefficient

In a previous post, I wrote about the wealth gap in the UK and I should acknowledge that I started with the preconceived view that there was indeed a wealth gap. What I mean by a wealth gap (and I presume this is roughly consistent with what is generally meant) is that wealth/income is distributed in such a way that a small portion of the population get most of the income. By the end of the post, I found myself slightly confused and although the numbers I had looked up didn’t indicate that there wasn’t a wealth gap, they also didn’t seem to indicate that there was. One of the problems is probably that simply considering numbers like median and mean income and looking at graphs showing how income is distributed doesn’t necessarily allow one to determine if there is indeed a income gap.

There is, however, a way of quantifying the income distribution. This is known as the Gini coefficient which is determined from the Lorentz curve. The Lorentz curve (shown in the figure on the right) shows what percentage of the total income the bottom x % of households have. If income is completely evenly distributed, the Lorentz curve is a diagonal line known as the line of equality (bottom 10% have 10% of the income, bottom 50 % have 50 % of the income etc.). Lorentz_curve The other extreme is the case where one person has all the income and everyone else has nothing. The Lorentz curve would then be a straight horizontal line along the x-axis that suddenly turns up at the end. In reality the Lorentz curve is somewhere between these two extremes. The Gini coefficient is then the ratio of the area between the line of equality and the Lorentz curve itself (A) and the total area below the line of equality (A+B). In the figure shown the Gini coefficient is A/(A+B). If we assume that the x and y axes run from 0 to 1 (rather than from 0 – 100 %), A+B = 0.5 and the Gini coeffiicient is 2A. The Gini coefficient would then be a number between 0 and 1, although it is sometimes multiplied by 100.

The Gini coefficient can vary wildly throughout the world, with poorer countries tending to have larger Gini coefficients. Namibia has one of the largest Gini coefficients (0.71) while Sweden has one of the lowest (0.23). The UK has a Gini coefficient of about 0.34 while the USA has a Gini coefficient of about 0.45.

So, what does this all mean? The UK has a Gini coefficient that appears to be quite similar to many other developed nations, although there are a number of countries that do have considerably lower Gini indexes (Norway, Sweden, Germany, Belgium, to name a few). What is possibly more interesting is that the UK’s Gini coefficient has changed quite considerably in the last 30 years, increasing from about 0.24 in the late 1970s to about 0.34 (maybe even 0.38) today. There appears, in the UK at least, to be a general view that it is worth giving most of the income to a small proportion of the population (in theory the most motivated, creative and skilled members of our society) because this will lead to economic growth and wealth will anyway then trickle down to the rest of society. If this were true you might expect there to be a significant change in Gross Domestic Product (GDP) growth rates in the last 30 years or so because the highest earners are taking a bigger fraction of the total income today than they were in the late 1970s. This doesn’t however, seem to be the case. According to the IMF data the growth rate of UK GDP has been highly variable from 1980 till today. It does not seem to be the case that as a smaller proportion of the population has taken a larger portion of the income, there has been a corresponding rise in the growth rate of the UK economy.

All in all, it seems that the UK has a Gini coefficient that is similar to other developed nations and doesn’t seem to indicate some kind of massive wealth gap. The wealth/income distribution has however changed quite substantially over the last 30 years or so with a bigger fraction of the income going to a smaller fraction of the population. If this has lead to a corresponding rise in GDP, ultimately benefiting everyone, this may seem perfectly reasonably. This, however, doesn’t seem to be the case. It’s my view, therefore, that we should be aiming to optimise GDP together with the Gini coefficient. There is no point in having a small Gini coefficient if the GDP is so low that no one has any wealth. By the same token, there is no point (at least not for the majority) in having a large Gini coefficient if again the GDP is such that the majority of the population is living in poverty. If anything, being moderately socialist, I feel that we should be aiming to reduce the Gini coefficient (i.e., distributing wealth more evenly) until it appears to be having a negative impact on GDP at which point we could assume that we have reached the optimum wealth distribution. A smaller Gini coefficient and we would start having a negative impact on the economy. A larger Gini coefficient and we would be giving more income to a smaller proportion of society for no real obvious reason.

Data is from various sources including wikipedia, the CIA world handbook, and the IMF

The British Space Agency

Today is the start of a 12 week consultation to help decide whether or not the UK should start a British Space Agency. Currently British space interest are overseen by the British National Space Council (BNSC) . The BNSC does not currently have much power and it appears that much of the UK’s involvement in space is somewhat disjointed and disorganised. If the goal is to create a single agency that will oversee and directly manage all of the UK’s involvement in space in a coherent and sensible way, this may well be a good thing. My impression, however, is that the goal is somewhat more than simply coordinating current activities.

The UK is already has a reasonably active space sector involved in building satellites or parts of satellites. According to the Department of Business Innovations and Skills’ press release, this sector employs 68000 people and generates 6.5bn for the UK economy. I have no idea where these numbers come from, but my initial impression is that they may have defined the space sector somewhat broadly. The creation of a British Space Agency suggests (and this is backed up by some of the wording in the BIS press relese) that there is a desire to spend more on the space sector. One rather selfish concern I have is that rather than this being new money (which seems unlikely in the current financial climate) this will simply be a redistribution of existing money, probably coming out of the existing research council’s budget. In theory the government has every right to reprioritise how it spends it’s money. What concerns me is that they will badge this as something that will benefit fundamental science and that all of us involved in anything related to space should be thankful that the government is committed to developing a vibrant space sector. Although fundamental science may well benefit from some space activities, it is my opinion that space activities should really be badged as technology development (i.e., essentially applied science). Of course if the government were to openly acknowledge that they were intending to cut funding for fundamental science in order to fund space activities because they regarded the resulting technology development as of more value than the results of fundamental science, I may well be disappointed, but at least I wouldn’t be able to accuse the government of being devious.

One of the arguments for increased spending in the space sector is that it will be of benefit to the UK economy through potential spin-offs and because this sector could engage in civil space activities that could generate income for the UK. There is, however, a view (a somewhat cynical one to be honest) that in fact the UK space industry is not actually viable and that the only way it can survive is to try and get some of the public money that is currently being spent on other research activities. If this is the case, then it is likely that the pressure to increase the UK’s involvement in space is coming from the industry itself, rather than from the scientific community. In 2007 the House of Commons Select Committee on Science and Technology decided that a UK Space Agency was only worth considering if there was a significant increase in civil spending in this sector. According to a recent BBC article Paul Drayson, the current Minister of Science believes, on the other hand, that increased UK involvement is worthwhile even if there is no increased commitment from the civil sector (or at least that’s how I have interpreted what he is quoted as saying). If the potential economic benefits are so great, why is the civil sector not clamoring to increase it’s investment in this area.

Well, what about the European Space Agency (ESA). Currently we spend about £250M a year to belong to ESA. Personally I happen to be in favour of the UK being more involved and embedded in Europe. The European Union (EU) may have issues to sort out, but in the long term we will be better off in the EU than not. Rather than investing additional money in a British Space Agency, why not simply become more engaged with ESA. ESA probably has some issues of its own, but if we engage more with it, we can play a role in redefining how it operates. Eventually (and this may take time) we can take pride – as Europeans – in a successful European Space Agency, rather than potentially being embarrassed that we tried and failed to operate a successful British Space Agency (maybe we won’t fail but space is so expensive that it seems unlikely that any countries other than China, Russia, the USA and maybe India can have viable, independent Space Agencies).

What do I think will happen? At the moment we seem to have a science minister (Paul Drayson) and a CEO of the Science and Technology Facilities Council (Keith Mason) who both appear to be in favour of more UK involvement in the space sector, so I think there will be a lot of pressure for this to go ahead. Do I think it’s a good idea? If ultimately a British Space Agency is formed that essentially optimises our existing involvement in ESA, then probably yes. If, on the other hand, Britain decides to carry out space activities independently of ESA, or in addition to what it does within ESA, then I suspect that we will regret this in the long run.

The Wealth Gap

I have recently become quite interested in the wealth (or more accurately income) distribution in the UK. This was partly motivated by a couple of what I thought were interesting articles by Polly Toynbee in the Guardian. In the first article (which I can no longer find – maybe it wasn’t Polly Toynbee) a group of people are asked if they believe that a wealth gap exists in the UK. Most answered that they did, but when asked to guess the salaries of some top earners (solicitors, investment bankers, etc.), they generally guessed salaries significantly lower that what these top earners typically earned.

In the second article (which you can find here ) a group of high earners are again asked some questions about the wealth distribution in the UK. More than 50 % of people in the UK earn less than what this group thought was the poverty line, and less than 1 % earned more than what this group thought would put you in the top 10 %. Essentially these two articles illustrate – or supposedly illustrate – that the lowest earners believe there is a substantial wealth gap, but don’t realise quite how big it is, and the highest earners believe there isn’t really a substantial wealth gap, but only because they don’t really realise how little most people earn.

Although I haven’t investigated this in extensive detail, I have looked up some numbers related to the distribution of wealth in the UK. When considering any distribution it is quite important to understand the difference between things like the median and the mean (Stephen Jay Gould has an excellent book called Full House that explains some of these statistical terms extremely clearly). In the UK in 2004/2005 the mean annual income (pre tax) was about £23000. This, however, can be distorted by a small proportion of the population earning extremely high salaries. A better measure is the median which tells you, in some sense, the middle salary (i.e., 50 % of the population earns less than the median and 50 % earns more). In 2004/2005 the median, pre-tax income was about £16500, significantly less than the mean.

Although the median income has increased somewhat since 2004/2005, to something around £18500, I still find it quite remarkable that 50 % of the British working population earn £18500 per year or less. If, rather than considering indivduals, one considers households, it is slightly higher, but not by much. The mean household income for 2004/2005 was £31800 while the median was £24700. Again, these numbers will have increased slightly in the last couple of years, but I still find somewhat disturbing that 50 % of households survive on about £25000 or less, but does this indicate the presence of a wealth gap in the UK? Certainly, trying to run a household on less than £25000 per year must be pretty tough. That the top 1 % of earners have salaries more than 17 times greater than the bottom 10 % may suggest that a gap does indeed exist.

None of these numbers, however, convincingly illustrates that there is a substantial wealth gap in the UK. I then found a figure from the government’s office of national statistics which illustrates to a certain extent how wealth is redistributed. The figure (which you can read more about here) shows the average annual household income broken up into 5 groups (bottom 20 %, next 20 % etc. – known as quintile groups). household income The dark blue columns are the original annual household incomes and the light blue columns show the annual household incomes after tax and benefits. The bottom 20 % more than double their income to about £ 15000 per year, while the top 20 % lose almost 30 % of their income. The median (which would be roughly the 3rd quintile group) have a household incomes of just over £20000 per year which isn’t affected much by tax or benefits. The figure suggests that the top 20 % have average household incomes only 3 times greater than the bottom 20 %. The figures also suggests that the top 40 % of households end up with about 60 % of the total amount of money earned in a year, and the top 20 % end up with about 37 % of the total. Does this suggest an unfair distribution – I don’t really know. My first impression was that it actually looks quite reasonable.

Having started this post expecting to illustrate that there is indeed a wealth gap in the UK, I am finding myself now less convinced than I was when I started (interestingly Polly Tonybee was on the BBC news this morning stating once again that the UK – along with the US – does indeed have a very big wealth gap). Having said that, I do still find it disturbing that most households survive on less than about £25000 per year (after tax and benefits). I have also been using wealth here to mean income, so this doesn’t really illustrate how the actual wealth is distributed. Most of the numbers here are also based on taxable income. What I also don’t know is how much of the country’s income is given out in a manner that allows the receiver to avoid tax and therefore isn’t included in the analysis here. I was going to continue and talk about the Gini index which is an index for illustrating how income/wealth is distributed in a country but, since this is already quite long, I will leave it for a later post.

The value of a PhD

As I mentioned in my first post, I am an academic at a British university.   As many people are probably aware, the number of students going to University in the UK has increased dramatically in the last decade or so. Although this a subject that could be debated at length, this is not the subject of this post.  What concerns me is the apparent desire to increase the number of students doing PhDs.  My impression of why this is happening is that some – politicians for example – believe that industry likes people with PhDs and therefore we should generate more of them. Although I can quite easily believe that people who have done PhDs and then gone into in industry have generally done well, it’s not obvious that this implies that we should generate more people with PhDs.

One of the reasons I feel that simply generating more PhDs is not the right approach is that – in my view – there are primarily two reasons why people with PhDs do well in industry. One is that a PhD teaches skills that will be useful in whatever career a PhD graduate ends up choosing.  The other is that these people are in general highly creative, motivated, and academically gifted. What, I presume, industry really likes is creative, motivated people and if they have the skills that a PhD teaches them, even better. If there are plenty of people with these basic skills who wanted to do PhDs I would have no real problem with increasing the number of PhDs. It is my view, however, that although in some academic fields there may be plenty of potentially talented PhD students, it is generally not the case (or at least if there are plenty of potentially talented PhD students, they are not clamouring to do PhDs in these fields).

The concern I have, therefore, is that universities will feel pressured to increase the number of students graduating with PhDs and to do so will select students who are not particularly suited to the degree.  Currently, at least in my field, a PhD student is expected – with some help from their supervisor – to work independently and ideally to take control of their project and make it their own. A PhD student is therefore, to a certain extent, someone who could later have an academic career. It doesn’t matter if they don’t actually go on to have an academic career, their abilities and skills will be valuable assets in whatever career they choose to follow. 

There are some,  however, who feel that  a PhD should simply teach students certain useful research skills because this is what UK industry wants.  It may well be true that UK industry would benefit from an increase in the number of people with research skills, but it is not completely clear that the best way to do this is to increase the number of PhD graduates. It is my opinion that it would be better to introduce degrees (such as research Masters) that are shorter than PhDs and focus on teaching research skills, and leave the PhD as a degree for those particularly interested in independent research and potentially interested in a career in academia.  This would protect the value of a PhD degree and still increase the number of graduates with valuable research skills.

A concern I have had in writing this post is that – if anyone actually reads it – it will be interpreted as an argument for keeping PhDs selective and exclusive, and that is certainly not the case.  I have no particular issue with there being more PhD students as long as they have the necessary skills and abilities to carry out a PhD.   My basic argument is that if UK industry would benefit from an increase in the number of people with basic research skills (as I suspect it would) we should have degrees specifically designed to teach these skills rather than potentially damaging a degree that has already proven its value and that does more than simply teach research skills.

First post

Well, I’ve been debating with myself for some time about starting a blog.  I don’t really have a good reason for doing so.  One reason is probably because I have been reading blogs for a while now and am interested to know if it is something I can do, and keep doing.  It is quite possible that I may get bored with this and give up straight away.  Another is probably because I have a habit of pontificating – to myself and to others – about various things that I happen to feel strongly about at that particular time. The idea of trying to articulate some of the these thoughts is somewhat appealing, if only to see if they make any sense in writing.

A little about myself.  I’m married, have 2 children, a cat and am an academic at a British university.  I’ve decided to keep this blog anonymous and have decided at this stage not to even say what field I work in – although this may become obvious if this blog continues.  I have no strong reasons for remaining anonymous.  I don’t have any expectation that what I will say will be particularly controversial and am not really interested in saying things that will annoy or antagonize others.  One  reason is probably because I expect that I will say things that in retrospect will seem rather stupid and so would rather people didn’t know who I was.  Another – if I was being honest – is probably because I will find it easier to say what I want to, being anonymous, than I would if I wasn’t.

Finally, the name of the blog.  It’s partly because it indicates my political leanings but is largely because all the other titles/usernames I could think of had already been taken.  What I am finding interesting is that as I get older – and I would to think as I get to understand the world slightly better – I am moving further from the centre, and to the left,  than I was expecting.  The title may have been better as “Far to the left of centre,” but that didn’t seem to roll off the tongue quite as well as the one I have chosen.