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That’s exactly what I mean. The correlation is, of course, not perfect – there are plenty of very famous professors who also make great mentors. But in general very famous professors do not have time to devote to undergraduates – or even graduate students – and in fact have such huge labs that you’d never see them anyway.</p>
<p>A letter of reference from a world famous professor(particularly in the sciences) carries weight only if you are applying for M.D./Ph.D. or M.D. with a very serious interest in an academic research career (this happens at the very top medical schools). It carries little weight if your goal is to be practicing physicians and your application reflects that direction. In most cases, a letter from a faculty member who knows you well and can attest to your academic abilities and character will be more helpful and informative to the committee. When renowned scientists write letters of recommendation, they may know your personally and attest to some of your personal qualities in the letter; however, their letter is essentially a stamp of approval as they put their academic reputation on the line to asses your potential to be an outstanding future physician-scientist-very different than a practicing physician. These types of letters can be very helpful for M.D./Ph.D applicants as the selection committee will trust the assessment by an experienced scientist who has evaluated students and peers in many different contexts, and can accurately comment on the candidates potential in research. Otherwise, such letters will say very little other than you took their course and did well or perhaps worked in their lab. In the latter case, I would think they would only take students who would be seriously thinking about science as part of their career plans as they will have the cream of the top science students, including those who are considering a Ph.D. program only.</p>
<p>If you’ve been working closely with a postdoc in the lab of a bigshot professor, would a LOR co-signed by the postdoc and the professor count as much as a letter from the professor himself?</p>
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I’ve never heard of such thing. How could a LOR be co-signed by the postdoc and the professor, and why is the postdoc’s signature necessary?</p>
<p>Post docs signature is necessary if the post doc wrote the letter. Otherwise it is plagiarism. Academics are prickly about such things.</p>
<p>However, a letter from a professor is much better than that of a post doc. Much, much better. Post docs are considered still students, and lack the breadth of experience to have a basis for comparison. If you are in this position, much better to have the professor speak with the post doc, then write her/his own letter. That letter can mention that the undergrad worked with a post doc, but the committee wants to know what the professor thinks, not what the post doc thinks.</p>
<p>Agree with Afan and Ysk1. Post-docs are trainees and Admissions Committees would not consider them to have the experience or qualifications to fully assess your performance and potential.</p>