David Stern's Blog on Energy, the Environment, Economics, and the Science of Science
Wednesday, June 29, 2011
2012 International Association for Energy Economics Conference in Perth
The 2012 conference of the International Association for Energy Economics (publisher of the Energy Journal) will be in Perth from June 24th-27th. The deadline for paper submissions is 13 January 2012. There will be two types of paper sessions - 15 minute presentations (including questions) and 30 minute presentations with formal discussants. In order to be considered for the latter you need to submit a full paper by the deadline, whereas a 1-2 page abstract is sufficient for the former.
The conference theme "will be to examine the dynamism of the world energy sectors in the context of what effect the Kyoto Process, which ends in 2012, had on the energy markets, technologies, and systems of the world, as well as what technological and market developments occurred in spite of the Process" but papers on all other topics in energy economics can be submitted.
Sunday, June 26, 2011
What is Ecological Economics?
So, time for another "serialization" in the spirit of John Quiggin's Zombie Economics and my earlier serialization of my Ecological Economics Reviews article. This time I have to write an encyclopedia article on "ecological economics". I only get 2000 words. This first very rough draft of the first section is titled "What is Ecological Economics?". Please contribute your insights and criticisms even though, unfortunately, I don't get to do an acknowledgements section.
Ecological economics is a relatively new interdisciplinary field concerned with the relationship between economic systems and the biological and physical world. Opinions differ on whether ecological economics is a transdisciplinary field comparable to say international relations, a new disciplinary paradigm in economics, a new field within mainstream economics, or even a subarea within the conventional economics field of environmental economics [refs].
The most common view, which is also the position taken by the International Society for Ecological Economics and the journal Ecological Economics, is that ecological economics is a transdisciplinary field. It recognizes that practical solutions to pressing social and environmental problems require new interdisciplinary approaches that focus on the links between economic, social, and ecological systems. Neither the traditional practice of economics alone nor the natural sciences on their own are held to be sufficient for addressing these issues or explain the past history of the human-environment system either.
In this view, the starting point and central organizing principle of ecological economics is that economies are embedded and dependent upon the ecosphere – they are part of a larger system (should we have a figure here?). Study of this joint environment-economy system must take into account natural science principles from thermodynamics, ecology etc. and also principles from psychology and other social sciences. So ecological economics integrates economics and various social and natural sciences (not just ecology).
“Ecological economics” is the name given to the field because:
1. Many ecologists were involved early on in the history of ecological economics.
2. The main antecedent to ecological economics was a biophysical economics that focused on energy flows in the human ecosystem.
3. Both economics and ecology share the Greek root “oikos” meaning "house" or "place to live". Ecology is the study of how organisms interact with their environment, support themselves, and interact with each other. Economics is the same applied to people [Wonnacott and Wonnacott, 1979; Common, 1995].
In practice, more economists than non-economists have been attracted to the emerging field and so it is natural for some of these economists to see ecological economics as a new paradigm in economics alongside existing paradigms such as the mainstream neoclassical economics and the alternative Post-Keynesian, Institutional, Marxist, and other paradigms. They argue that ecological economists must reject the neoclassical approach to economics [Spash], though there is no one single school of thought that all agree on to replace the mainstream paradigm. But there are also natural scientists who believe that ecological economics can overturn and replace mainstream economics [Hall et al.]. Both these groups reject the core model of neoclassical economics – that economic theory should be primarily based on modeling the decision-making processes of individual consumers and firms with the default assumption that these agents maximize utility or profits. Røpke discusses tensions between mainstream neoclassical economists and socio-economists in ISEE [Røpke].
However, both subscribers to the transdiscipline view who otherwise practice the neoclassical economic approach and those who reject mainstream economics share a common set of assumptions and approaches. Namely that:
1. The economy is just a sub-system of the larger human-environment system.
2. Models of the economy must comply with biophysical principles and that mainstream economics is guilty of underemphasizing the role of natural science.
3. Economic policy must consider jointly the objectives of efficiency, equity, and sustainability, instead of the primary emphasis on efficiency in mainstream economics. Ecological economics has been characterized as “sustainability science” [ref].
4. That there are limits to our ability to substitute human made inputs and knowledge for natural resources and the environment in both production and consumption [Stern, 1997].
There is also a tension between ecological economics as science or as activism. This is illustrated by efforts to get ISEE and USSEE to adopt positions on zero economic growth.
By contrast, many mainstream environmental economists think of ecological economics as either a new field within mainstream economics that deals with the management of complex ecological systems or as a subfield within the field of environmental and resource economics [Røpke, 2005]. This is reflected in the code given to ecological economics by the Journal of Economic Literature as part of its classification system of the economic literature: Q57 – a subfield within environmental economics.
Ecological economics is a relatively new interdisciplinary field concerned with the relationship between economic systems and the biological and physical world. Opinions differ on whether ecological economics is a transdisciplinary field comparable to say international relations, a new disciplinary paradigm in economics, a new field within mainstream economics, or even a subarea within the conventional economics field of environmental economics [refs].
The most common view, which is also the position taken by the International Society for Ecological Economics and the journal Ecological Economics, is that ecological economics is a transdisciplinary field. It recognizes that practical solutions to pressing social and environmental problems require new interdisciplinary approaches that focus on the links between economic, social, and ecological systems. Neither the traditional practice of economics alone nor the natural sciences on their own are held to be sufficient for addressing these issues or explain the past history of the human-environment system either.
In this view, the starting point and central organizing principle of ecological economics is that economies are embedded and dependent upon the ecosphere – they are part of a larger system (should we have a figure here?). Study of this joint environment-economy system must take into account natural science principles from thermodynamics, ecology etc. and also principles from psychology and other social sciences. So ecological economics integrates economics and various social and natural sciences (not just ecology).
“Ecological economics” is the name given to the field because:
1. Many ecologists were involved early on in the history of ecological economics.
2. The main antecedent to ecological economics was a biophysical economics that focused on energy flows in the human ecosystem.
3. Both economics and ecology share the Greek root “oikos” meaning "house" or "place to live". Ecology is the study of how organisms interact with their environment, support themselves, and interact with each other. Economics is the same applied to people [Wonnacott and Wonnacott, 1979; Common, 1995].
In practice, more economists than non-economists have been attracted to the emerging field and so it is natural for some of these economists to see ecological economics as a new paradigm in economics alongside existing paradigms such as the mainstream neoclassical economics and the alternative Post-Keynesian, Institutional, Marxist, and other paradigms. They argue that ecological economists must reject the neoclassical approach to economics [Spash], though there is no one single school of thought that all agree on to replace the mainstream paradigm. But there are also natural scientists who believe that ecological economics can overturn and replace mainstream economics [Hall et al.]. Both these groups reject the core model of neoclassical economics – that economic theory should be primarily based on modeling the decision-making processes of individual consumers and firms with the default assumption that these agents maximize utility or profits. Røpke discusses tensions between mainstream neoclassical economists and socio-economists in ISEE [Røpke].
However, both subscribers to the transdiscipline view who otherwise practice the neoclassical economic approach and those who reject mainstream economics share a common set of assumptions and approaches. Namely that:
1. The economy is just a sub-system of the larger human-environment system.
2. Models of the economy must comply with biophysical principles and that mainstream economics is guilty of underemphasizing the role of natural science.
3. Economic policy must consider jointly the objectives of efficiency, equity, and sustainability, instead of the primary emphasis on efficiency in mainstream economics. Ecological economics has been characterized as “sustainability science” [ref].
4. That there are limits to our ability to substitute human made inputs and knowledge for natural resources and the environment in both production and consumption [Stern, 1997].
There is also a tension between ecological economics as science or as activism. This is illustrated by efforts to get ISEE and USSEE to adopt positions on zero economic growth.
By contrast, many mainstream environmental economists think of ecological economics as either a new field within mainstream economics that deals with the management of complex ecological systems or as a subfield within the field of environmental and resource economics [Røpke, 2005]. This is reflected in the code given to ecological economics by the Journal of Economic Literature as part of its classification system of the economic literature: Q57 – a subfield within environmental economics.
Saturday, June 25, 2011
S.A.P.I.E.N.S.
Another new journal, though actually it has been published since 2008: S.A.P.I.E.N.S. - Surveys and Perspectives Integrating Environment and Society. This is an open-access journal, which is also free for authors to publish in. It is funded by French MNC Veolia Environnement through their non-profit research foundation. The inaugural issue featured articles by Esther Duflo and Bob Costanza. Costanza, Elinor Ostrom, Rajendra Pachauri inter alia are on the editorial board. It's not yet catalogued in Scopus or the Web of Science but you can find its articles in Google Scholar.
Tuesday, June 21, 2011
Reviews in Ecological Economics
After two years of publishing Ecological Economics Reviews (EER) as a special issue of the Annals of the New York Academy of Sciences, Bob Costanza, Karin Limburg, and Ida Kubiszewski are announcing a move - to Springer - and a slightly different name: Reviews in Ecological Economics (REE). They are confident that this move will strengthen the new REE and increase its exposure and recognition.
They are now inviting submissions to this year's volume of Reviews in Ecological Economics to be published early 2012. The mission of REE has not changed from it prior existence as EER – it will provide authoritative reviews of key topics in ecological economics. REE will be published annually.
The deadline for submissions is 30th October. Guidelines for authors can be found on the Springer website. Submit papers to Ida Kubiszewski.
They are now inviting submissions to this year's volume of Reviews in Ecological Economics to be published early 2012. The mission of REE has not changed from it prior existence as EER – it will provide authoritative reviews of key topics in ecological economics. REE will be published annually.
The deadline for submissions is 30th October. Guidelines for authors can be found on the Springer website. Submit papers to Ida Kubiszewski.
Nature Publishing Group Goes Head to Head with PLoS ONE
Nature Publishing Group is launching yet another journal: Scientific Reports. It is an open access journal with the same $US1,350 publication fee as PLoS ONE. Nature recently launched another journal: Nature Communications that charges a $US5,000 open access fee, which is higher than any of the PLoS journals and the highest publication fee that I've seen. It's not a pure open access journal though. The new journal has the same editorial policy as PLoS ONE: "It will not set a threshold of perceived importance for the papers that it publishes; rather, Scientific Reports will publish all papers that are judged to be technically valid and original." The initial editorial board composition suggests that this journal will be less biology focused than PLoS ONE. Actually, they will not accept papers on clinical research, so their niche is a little different to PLoS ONE.
Sunday, June 19, 2011
Special Issue of Energy Economics
The latest issue of Energy Economics is a special issue on the economics of technologies to combat global warming. I haven't read the papers in detail yet, but there look to be several good overviews of the current state of play on the key issues in this area. Given the slowness with which countries are moving to put a price on greenhouse gas emissions, technology policies might end up being more important in driving the transition to a lower carbon future.
The special issue is edited by William Nordhaus and Nebojsa Nakicenovic. I'm going to be reading them in preparation for the lectures I will give later this year in the Crawford course Government, markets and global change. My lectures are on the general topic of energy and the global environment with a particular focus on alternative energy technology policy. The course is a team taught course that uses cases studies to structure the lecture content. We are using a case study on US DOE funding for alternative energy technologies. I imagine these papers would also feed into writing my sections of our IPCC 5th Assessment Report chapter.
The special issue is edited by William Nordhaus and Nebojsa Nakicenovic. I'm going to be reading them in preparation for the lectures I will give later this year in the Crawford course Government, markets and global change. My lectures are on the general topic of energy and the global environment with a particular focus on alternative energy technology policy. The course is a team taught course that uses cases studies to structure the lecture content. We are using a case study on US DOE funding for alternative energy technologies. I imagine these papers would also feed into writing my sections of our IPCC 5th Assessment Report chapter.
Episode 3
Evolutionary biology, HIV, and the Central African World War... This one is even more out there... There is more about the series on Wikipedia.
Episode 2: All Watched Over by Machines of Loving Grace
This episode should be of interest to ecological economists:
It starts off with a discussion of the history of ecology including the Odum brothers as well as Jay Forrester and cybernetics. It goes on to the Club of Rome and The Limits to Growth and then to more recent developments in ecology. One of the themes is the rise in people's understanding of the world as an interconnected system. Today, conservatives, in the American sense, and libertarians seem to be people who think the interconnected system is inherently stable and self-regulating, whereas "liberals" think it is unstable and unpredictable but still somehow controllable by collective action.
It starts off with a discussion of the history of ecology including the Odum brothers as well as Jay Forrester and cybernetics. It goes on to the Club of Rome and The Limits to Growth and then to more recent developments in ecology. One of the themes is the rise in people's understanding of the world as an interconnected system. Today, conservatives, in the American sense, and libertarians seem to be people who think the interconnected system is inherently stable and self-regulating, whereas "liberals" think it is unstable and unpredictable but still somehow controllable by collective action.
Review of the Publish or Perish Bibliometrics Software
Publish or Perish (PoP) is a freeware interface for deriving citation metrics from Google Scholar (GS). I downloaded it, wrapped it up as a Mac application using Wineskin and ran it. The three most useful features of the software are:
1. It automatically computes a bunch of statistics such as the h-index from the GS results.
2. It allows you to merge together the multiple entries for a single paper that GS sometimes generates For example, my 1996 paper in World Development is scattered across multiple entries. This reduces the citation count of the main entry and introduces some bogus publications into the calculation of my h-index. By dragging and dropping the various entries returned you can merge them together into a single entry. The h-index and other statistics recompute automatically.
3. It allows you to sort GS results by title, publication, year of publication, and authors. The standard Google Scholar output is only presented in order of the number of citations, so this could be really useful.
The most common type of analysis is likely to be one for the impact of individual authors, which is the normal application of the h-index and other statistics. PoP can also do analyses of the impact of journals by computing their h-index and other metrics as well as general literature and citation searches. The Publish or Perish book gives lots of examples of the various types of searches.
Accuracy in computing citations analyses for individual authors will depend on two things:
1. How common the name of the person is.
2. If the name is common, how interdisciplinary the person is.
For someone with a unique two initial name (i.e. D. I. Stern) the results are somewhat accurate. Searching for D. I. Stern captures about 83% of my total citations on Google Scholar. The main discrepancy is again the World Development paper listed under D. Stern. There is no way to merge the results of two different searches. Searching for "D Stern" excluding "D* Stern" (which also excludes "DI Stern") generates more than 1000 hits itself and only the first 1000 are counted. Narrowing down the search by subject area excludes a lot of my publications due to my interdisciplinarity. Normally I run one GS search for "DI Stern" in all subject areas and then a second search for "D Stern" excluding "DI Stern" in Business and Economics only.* You can do these two searches in PoP but you can't merge them and get the h-index etc. for the combined search. Of course, you can copy the data retrieved and paste it into a spreadsheet and do this analysis yourself.
So for analyses of scholars with common single initial names (and mine is hardly the most common!) and publications across different disciplinary areas you will likely not find the software to be really user-friendly at the moment though better than using Google Scholar directly. Still, for people like me with a unique combination of two initials it will be fairly accurate in most cases, and using PoP to do a series of searches and then combining them in a spreadsheet should be easier than direct use of GS. If the researcher in question has a unique single initial name like F. Jotzo, J. Pezzey, or T. Kompas then the software is going to be a lot more useful and accurate.
* The main issue here seems to be that if you exclude any one subject area from the Google Scholar search articles in Nature are not included in the results. Two of the articles in my h-index are in Nature.
1. It automatically computes a bunch of statistics such as the h-index from the GS results.
2. It allows you to merge together the multiple entries for a single paper that GS sometimes generates For example, my 1996 paper in World Development is scattered across multiple entries. This reduces the citation count of the main entry and introduces some bogus publications into the calculation of my h-index. By dragging and dropping the various entries returned you can merge them together into a single entry. The h-index and other statistics recompute automatically.
3. It allows you to sort GS results by title, publication, year of publication, and authors. The standard Google Scholar output is only presented in order of the number of citations, so this could be really useful.
The most common type of analysis is likely to be one for the impact of individual authors, which is the normal application of the h-index and other statistics. PoP can also do analyses of the impact of journals by computing their h-index and other metrics as well as general literature and citation searches. The Publish or Perish book gives lots of examples of the various types of searches.
Accuracy in computing citations analyses for individual authors will depend on two things:
1. How common the name of the person is.
2. If the name is common, how interdisciplinary the person is.
For someone with a unique two initial name (i.e. D. I. Stern) the results are somewhat accurate. Searching for D. I. Stern captures about 83% of my total citations on Google Scholar. The main discrepancy is again the World Development paper listed under D. Stern. There is no way to merge the results of two different searches. Searching for "D Stern" excluding "D* Stern" (which also excludes "DI Stern") generates more than 1000 hits itself and only the first 1000 are counted. Narrowing down the search by subject area excludes a lot of my publications due to my interdisciplinarity. Normally I run one GS search for "DI Stern" in all subject areas and then a second search for "D Stern" excluding "DI Stern" in Business and Economics only.* You can do these two searches in PoP but you can't merge them and get the h-index etc. for the combined search. Of course, you can copy the data retrieved and paste it into a spreadsheet and do this analysis yourself.
So for analyses of scholars with common single initial names (and mine is hardly the most common!) and publications across different disciplinary areas you will likely not find the software to be really user-friendly at the moment though better than using Google Scholar directly. Still, for people like me with a unique combination of two initials it will be fairly accurate in most cases, and using PoP to do a series of searches and then combining them in a spreadsheet should be easier than direct use of GS. If the researcher in question has a unique single initial name like F. Jotzo, J. Pezzey, or T. Kompas then the software is going to be a lot more useful and accurate.
* The main issue here seems to be that if you exclude any one subject area from the Google Scholar search articles in Nature are not included in the results. Two of the articles in my h-index are in Nature.
Saturday, June 18, 2011
Crawford School Working Papers on SSRN
I still don't quite get how SSRN works despite having my own page on there. All Crawford School papers that are on SSRN are now included in the Australian National University Crawford School of Economics & Government Research Paper Series. But the Crawford School has also launched a new working paper series on SSRN titled Crawford School Research Papers. We have a bunch more paper series too as well as series of centres like CCEP.
Journal of Environmental Studies and Sciences
A new journal for a new academic society: Association for Environmental Studies and Sciences. I've long thought it strange that there has been no professional society for environmental studies. Well, apart from the International Society for Ecological Economics of course :) This makes academic job searches in environmental studies a bit more challenging than in other fields, for example. Unlike ISEE, the society is limiting itself to academics and students only. It's also focusing on North America, though not limited to it. The Association has its conference next week at the University of Vermont.
Advice on Getting Published
Via Marginal Revolution a newsletter with a bunch of advice about getting published. Seems to make sense to me given my experience in publishing and being a referee for more than 50 journals and associate editor for Ecological Economics.
All Watched Over By Machines of Loving Grace
An interesting take on the history of America in the last couple of decades. At least that's what I think it's about:
Friday, June 17, 2011
Follow Up on SD Cards
After my flash drive died I finally followed up on my idea of using an SD Card instead. The drive died after being knocked one too many times while plugged into my laptop.
I bought a Dick Smith brand card as I wanted to get one right away after the flash drive died. It claims to be a Class 4 card but so far it seems to be extremely slow when writing data from my computer onto the card. This is rather disappointing.
And if you don't push the card into the SD slot fast enough it may not mount. At first I thought the card was a total dud!
Copying from the card to my laptop does appear to be acceptably fast. Here are the stats from XBench:
Comparing the results to those from a Lexar flashdrive and a 2005 vintage Sandisk SD card these stats seem to combine the weaknesses of both those systems.
I bought a Dick Smith brand card as I wanted to get one right away after the flash drive died. It claims to be a Class 4 card but so far it seems to be extremely slow when writing data from my computer onto the card. This is rather disappointing.
And if you don't push the card into the SD slot fast enough it may not mount. At first I thought the card was a total dud!
Copying from the card to my laptop does appear to be acceptably fast. Here are the stats from XBench:
Comparing the results to those from a Lexar flashdrive and a 2005 vintage Sandisk SD card these stats seem to combine the weaknesses of both those systems.
Wednesday, June 15, 2011
The "Google Way" to Visualize Research
Yesterday, I showed one potential way of visualizing my research areas. Another way is using the web to tell us just like Google does. In fact, I did a Google Scholar search on myself and then put the results (with some cleaning up) into Wordl:
I could have also cleaned out my name from the data first (using the replace function in Word) but decided against that. Some of the topics from yesterday's post are clearly here but you need to know how to "connect the dots" to understand the links between them.
I could have also cleaned out my name from the data first (using the replace function in Word) but decided against that. Some of the topics from yesterday's post are clearly here but you need to know how to "connect the dots" to understand the links between them.
Tuesday, June 14, 2011
Visualizing Research Areas and Links
I've been trying to give an overview of my research for a presentation and came up with this:
I've tried to fit various of the topics I've worked on in the last decade within three disciplinary fields and the overlaps between them. In the middle I put "Meta" to represent my interest in meta-analysis and bibliometric analysis. This doesn't cover everything. My recent energy efficiency stuff is subsumed into energy and growth or EKC but it mostly covers the relevant topics. The variety of topics is one reason that I called this blog "stochastic trend". It's something of a random walk around these various areas of interest.
BTW the image was created in Powerpoint 2004 (Mac version) using "Autoshapes". I set the fills of the circles to 50% transparency to get the mixed colors where the circles overlap. There is a special tool for Venn Diagrams in the most recent version of Powerpoint.
I've tried to fit various of the topics I've worked on in the last decade within three disciplinary fields and the overlaps between them. In the middle I put "Meta" to represent my interest in meta-analysis and bibliometric analysis. This doesn't cover everything. My recent energy efficiency stuff is subsumed into energy and growth or EKC but it mostly covers the relevant topics. The variety of topics is one reason that I called this blog "stochastic trend". It's something of a random walk around these various areas of interest.
BTW the image was created in Powerpoint 2004 (Mac version) using "Autoshapes". I set the fills of the circles to 50% transparency to get the mixed colors where the circles overlap. There is a special tool for Venn Diagrams in the most recent version of Powerpoint.
Monday, June 6, 2011
New Private College of the Humanities in the UK
An interesting development in the face of the tremendous rise in tuition fees at public universities in the UK: "The New College of the Humanities. This will be a private college that is part of the University of London. It will grant London degrees and use their library facilities etc. There is star founding faculty of fourteen professors including well-known names like Richard Dawkins, Partha Dasgupta, Peter Singer, Niall Ferguson, Lawrence Krauss etc. I'm guessing that these guys though won't be doing a lot of the regular teaching, especially those based in the US... Fees are set at £18,000, which is double the UK public maximum of £9,000 but cheap by the standards of current US private university tuition. Students need to meet minimum University of London entry standards and will be interviewed.
The curriculum is broader than is traditional in the UK. This seems like a UK version of the American liberal arts college or what Oxford and Cambridge were once like with a focus on the humanities, one on one tutorials, and admission by interview.
Of course, a lot of people think this is a bad development. Part of the criticism seems to be based on the college using University of London facilities rather than creating their own. If the University isn't charging them market rates for their use then that is a problem. I suspect that they will make some good income out of this that will help fill the shortfall due to the government cuts. One difference with US models is that the college is a "for profit". A charitable trust is also being set up that will provide scholarships to 20% of the students in the first year.
Maybe I'm less shocked than some of these commentators because my experience of US higher education is entirely in the private sector both as a student and as a professor and public Australian universities charge these kinds of fees to graduate students (they waive fees to domestic PhD students). It's a different question whether it will be a good idea for students to get degrees from this place. It will be interesting to follow developments. For more comment see "Crooked Timber".
Friday, June 3, 2011
CCEP Working Papers in May 2011
As the summer vacation gets going in the northern hemisphere, downloads and abstracts views on RePEc usually decline. So as expected there was some decline in the number of downloads that we received. We now have 14 CCEP working papers. The most popular paper this month was Frank Jotzo's paper Carbon Pricing that Builds Consensus and Reduces Australia's Emissions: Managing Uncertainties Using a Rising Fixed Price Evolving to Emissions Trading, which was released in March.
Thursday, June 2, 2011
Price Floors in Emissions Trading to Reduce Policy Related Investment Risks: an Australian View
Frank Jotzo and Steve Hatfield-Dodds have a new CCEP working paper tiled: Price Floors in Emissions Trading to Reduce Policy Related Investment Risks: an Australian View, which is about the role of a price floor in a carbon emissions trading scheme in increasing the certainty of the investment environment. One of the downsides to emissions permit trading is that permit prices can be very volatile. This chart shows the EU ETS permit prices from just before the global financial crisis until later 2010:
On the other hand, a flexible price reduces the financial burden on firms during recessions. The paper looks at ways to have the best of both worlds in the most effective manner.
On the other hand, a flexible price reduces the financial burden on firms during recessions. The paper looks at ways to have the best of both worlds in the most effective manner.
Wednesday, June 1, 2011
IPCC Literature Deadlines
The following are the deadlines for papers that can be cited in the 5th IPCC Assessment Report. At least for Working Group III's contributions:
- Literature cutoff I: cited papers must be submitted to a journal (11 March 2013)
- Literature cutoff II: cited papers must be accepted by a journal (28 October 2013)