Generally I see the quality of an authors publication in the ability to be author on papers with changing co-authors over years that generally are better that the average. If a deeper analysis isn't possible I am looking for highly cited papers rather than a long publication list.

This shows that the researcher has flair for selecting to work on the good ideas, skills to get and analyse data and contributing with sufficient work effort that the papers actually are concluded. 

Dear Dr. Zulfiqar! Thank you for posting a question of very high consideration. This may or may not true in all cases. A researcher with a few research papers of high quality may be more capable and efficient with higher expertise than a researcher with long list of papers. In contrary, a researcher with many number of papers may or may not possess expertise of research. Writing a paper has now been emerged as an art. Some times long list has no relationship with the expertise or hard work.   

Generally I see the quality of an authors publication in the ability to be author on papers with changing co-authors over years that generally are better that the average. If a deeper analysis isn't possible I am looking for highly cited papers rather than a long publication list.

This shows that the researcher has flair for selecting to work on the good ideas, skills to get and analyse data and contributing with sufficient work effort that the papers actually are concluded. 

I think, a researcher in early stage can do this in some pressure, but later when they become a mature researcher, he understands that how to safeguard themselves from parasite experts.

Dear Rahul, Most of the Seniors pressurize juniors to do this and increases publication list and profile. mostly, junior fellows are victimize by this.

Yes, I agree to Dr. Zulfiqar views.

The problem is that not all researchers of the described type are indeed parasites.  Think about material scientists who prepare excellent quality samples of new materials.  They do not necessary use new methods of crystal growth, so they have only a dimm chance to publish a method of obtaining those new materials.  But those samples are given to few research teams to perform experiments and measurements of various kinds, mostly resulting in publications.  The same goes for X-ray folks who "merely" characterize new materials.  Without such an input the new article would never be published.  Do such people deserve to have their names listed among other authors?  Certainly yes (this is my own opinion, you may prefer thank you notes for them instead), but this fact alone doesn't mean they are experts in main subjects of those articles, of course.

Dear your question is true for consideration.It is fact you given.Only more papers with more authors not Gaines credit.Face boldly such practicenors.

Yes, Marek, you are quite right that all scientists are not like that. But the fact is that number of papers is not always depicting a quality research scientist, though it may be true in many cases. Therefore, it should not be taken as a criterion.

Maybe it is worthwhile to make a distinction between experts and scientists.  I can imagine a situation when a person is unable to propose or create anything really new but is nevertheless very knowledgeable in some domain.  Such a person may be much better than great scientist during negotiations with sponsors.  An expert will usually be able to tell you what was already done in your field, thus most likely being unpublishable.  On the other hand, the quality of authored papers usually (but not always!) may be judged by the number of their citations.  Large number of articles authored by a given researcher in some area means nothing else but personal engagement of this very researcher in this area, not necessarily the substantial progress.  Especially, when those articles look very similar to each other ...

Sorry, bureaucrats, there is no single, easy and universal measure of scientific quality.

Excellent question raised by Dr. Zulfikar and expertly answered by all colleagues from Pakistan and elsewhere. This is a huge problem in India too and becoming malignant. It was not a problem say thirty years ago. In ones field of sub-specialization  it is quite easy to detect when a author is genuine (one or two sub-fields of specialization) and when it is fake (suddenly papers appearing in a new field in which there was no contribution continuity from the past). At the end of the day I find that more than pressure  from bosses, it is younger colleagues including superiors names to please! The system is actively encouraging it. Attempts to break-up contribution as to who did what by some journals is also ridiculous. In one most prestigious open access  journal  (not difficult to guess), one can be an author even if one "supplied reagents" for the investiagtion.     

Question raise by you is quite interesting! Authorship mutualism is unresolved issue!

As with most things in life, quality is more important than quantity. As it is very difficult to determine the contribution made by co-authors on peer-reviewed publications, I think it's often better to look at how each author has engaged with the geoscience community, perhaps through speaking at conferences. Ultimately, if you're driving research yourself, there's no excuse for not being the first author on papers, or speaking about your work in public.

Perhaps it should be mandatory for the co-authors contribution to a research article be listed somewhere?

Difficult to answer the question. Nevertheless I agree up to some extent that the quantity of the research articles reflect the expertise of the author.

Sometimes YES and not always. 

Those are known as parasite authors.

If one has written in many dimensions with many authors, it gives an idea about parasite nature.

Dear Dr.Mirani

Thanks your good question. as we know, one of the most bad non ethical problems in scientific world is production of articles without any efforts by some percent of researchers. for example one of my collegues in Maragheh University of Medical Sciences has produced more that 400 papers in 3 years without smallest efforts in lab or a research center. but our national or international laws can not help to resolve or analysing such problems. in my idea universities shoudimplement such potent laws in publications, for example only original papers have accepting in promotions of scientific boards . vice versa in considering incitements for papers, money paid to original papers not other fake types.