CosmoCoffee Forum Index CosmoCoffee

 
 FAQFAQ   SearchSearch  MemberlistSmartFeed   MemberlistMemberlist    RegisterRegister 
   ProfileProfile   Log inLog in 
Arxiv New Filter | Bookmarks & clubs | Arxiv ref/author:

Impact Factor Journals for astro-ph papers
 
Post new topic   Reply to topic    CosmoCoffee Forum Index -> Teaching, Papers and Presentations
View previous topic :: View next topic  
Author Message
Alessandro Melchiorri



Joined: 24 Sep 2004
Posts: 123
Affiliation: University of Rome

PostPosted: February 16 2008  Reply with quote

Hi all,

I just discovered that with SPIRES is possible to evaluate the 2007
impact factors derived from papers in astro.ph.
This should be more useful than the usual impact factors that are derived from papers in different sectors of physics.
Let me explain it better: you can count the citations for the astro-ph
papers published on a specific journal. The you divide by the number of papers and you have a more focused impact factor.
Here we go:

Nature 5,93
ApJ 5,79
JCAP 5,67
PLB 5,65
PRD 5,37
PRL 4,67

So here my two cents:

- Physical Review Letters sucks. The astro-ph papers that are published there have generally less citations than in other journals !
I quite agree with this if I base it on my experience: PRD papers are generally more cited...and the PRL review process is often insane.

- The impact factor of Nature (27 ?) does'nt come from astro papers but from papers in other fields (biology?). Again, one should be extremely careful in judging a cosmo paper in Nature having 5 times more impact than a paper on PRD. They have almost the same impact.

What do you think ? Shocking eh ?
But it makes sense and people are still judging jobs and cv on impact factors...

cheers
Alessandro
Back to top
View user's profile   Visit poster's website
Syksy Rasanen



Joined: 02 Mar 2005
Posts: 127
Affiliation: University of Helsinki

PostPosted: February 16 2008  Reply with quote

Since many astro-ph papers from 2007 are not published yet, surely it would make more sense to look at 2006? Also, SPIRES does not always have publication info, esp. for astrophysics journals. (I guess NASA ADS would be better for this.)

For comparison, the usual impact factors (for 2006) are as follows:

Nature 26.7
PRL 7.07
JCAP 6.18
ApJ 6.12
PLB 5.04
PRD 4.90
Back to top
View user's profile [ Hidden ]
Alessandro Melchiorri



Joined: 24 Sep 2004
Posts: 123
Affiliation: University of Rome

PostPosted: February 16 2008  Reply with quote

Hi

The papers are the papers submitted and published in 2007 and SPIRES cover them all. Of course there may be paper submitted in 2007 and that will be published in 2008 but I see a trend here..

My point is that we should not believe in impact factors when we look at journals that publish papers in many areas.
There may be a paper on biology that has 1000 citations, you then publish a paper on cosmology on the same journal but this does'nt mean that 1000 biologists will read it ! it simply does'nt make sense !
Look at PRL. Just take a copy of this journal and you will see that it is now a journal for solid state physics (about 10 papers on it for every number against 1−2 in gravitation-astrophysics). So it is clear that the impact factor of this journal is driven by solid state physics, not astrophysics.
Moreover, what is the statistical meaning of this ? a journal can have 5 papers with 1995 citations and 95 with one citation but then the impact factor will be 20 ...
If you consider that usually CV's are judged on Impact Factors and that actually our institutions are paying for those silly numbers...

ciao
Alessandro
Back to top
View user's profile   Visit poster's website
Syksy Rasanen



Joined: 02 Mar 2005
Posts: 127
Affiliation: University of Helsinki

PostPosted: February 16 2008  Reply with quote

Alessandro Melchiorri wrote:
The papers are the papers submitted and published in 2007 and SPIRES cover them all.


Comparing SPIRES and ADS entries shows that SPIRES lacks publication data for a lot of astrophysics papers.

For example, picking (at random) the month June in 2007 on astro-ph, and looking at the first 10 papers, SPIRES has publication data for 1 of them, ADS for 7. (One of the papers is a proceedings, and two have no publication data in either SPIRES or ADS.)

Note that taking 2007 instead of 2006 biases the numbers against journals with a longer refereeing process.

I have no disagreement with your point itself.

I remember that there was correspondence in Nature in 2003 about how the citation rate of articles is not strongly correlated with the impact factor of the journals in which they are published, because the impact factor is typically driven by a small subset of highly cited articles. (I looked at the Nature site, but the contents seems to be subscriber only.)
Back to top
View user's profile [ Hidden ]
Alessandro Melchiorri



Joined: 24 Sep 2004
Posts: 123
Affiliation: University of Rome

PostPosted: February 16 2008  Reply with quote

Hi Syksy,

uhm..no I don't think there is a bias for PRL and Nature.
It may be that the overall impact factors I gave are inaccurate but I don't see why
this should be the case only for PRL and Nature (that are actually supposed to be faster
in acceptance or rejection than other journals).
I am afraid there is a real trend here: it seems that no higly cited paper in cosmology submitted in 2007 and accepted in the same year has been published in PRL ...
SPIRES gives me about 50 papers published on PRL ...I think is a good sampling.
So, I am afraid that the quality of PRL review process for astrophysical papers is going terribly down...let's see next year...my suspect is that they are leaving cosmology for solid state physics.

cheers
Alessandro
Back to top
View user's profile   Visit poster's website
Anze Slosar



Joined: 24 Sep 2004
Posts: 205
Affiliation: Brookhaven National Laboratory

PostPosted: February 17 2008  Reply with quote

Alessandro, why do you stress about it? Why does it matter? Only banana republics and some parts of Europe are obsessed with citation indices, SCI metrics and **** like that. Slovenia is particularly bad about that, for example they always reduce your output to two numbers

n1 = papers (impact)⁄(min(10, # authors))
n2 = #citations excluding self-citations (counted as any one author common on the cited and citer paper is a self-citation)

Then there is a minimum (n1,n2) for an assistant prof, etc. Grants are given based on some function of n1,n2. It is absolutely ridiculous. (and the min in eq 1 was due to particle physicists wanting to get some grants too, haha)

It is good that citations and papers do not have big weight as it is easy to write easy papers that anyone can understand, they state something obvious and you end up with a lot of citations. But they should count at least a little. The USA seem to be in a completely opposite limit (as far as I can tell). References are everything while papers and citations are irrelevant. Just a good reference from a respectable dude and you're done.
Back to top
View user's profile [ Hidden ] Visit poster's website
Alessandro Melchiorri



Joined: 24 Sep 2004
Posts: 123
Affiliation: University of Rome

PostPosted: February 17 2008  Reply with quote

Uhm,
between a letter from a respectable dude and the impact factor I would
actually prefer the impact factor ! :-)
My point is not that this kind of numbers are useless...just that they should be computed correctly. Impact factors should at least be considered only for specialized journals (jcap, ApJ, PRD) but not for journal as PRL of Nature that accept papers from very different fields.
Anyway I found this on wikipedia:
http://en.wikipedia.org/wiki/Impact_factor


cheers
Alessandro
Back to top
View user's profile   Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    CosmoCoffee Forum Index -> Teaching, Papers and Presentations All times are GMT + 5 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group. Sponsored by WordWeb online dictionary and dictionary software.