If a professor in a North American country presents his- or herself by his/her first name in email messages, does this mean that students can refer to him/her by his/her first name? Or is this generally not a good idea, unless the professor has explicitly mentioned that he/she can be referred to by first name? I've noticed that most professors, who prefer to be referred to more formally, do not sign their emails with just their first names, but usually initials or first and last name.
If you are a foreigner, then you can just ask. Most academics are used to deal with foreigners and know that such subtle and unwritten rules are hard to know. They recognize that just asking is often the least awkward solution.
It is always safe to ask. Throughout my undergrad and grad career, all my professors have always asked their students to call them by their first name. Some professors say this is because they respect you and because they don't address you as "Mr/Miss Smith", then you shouldn't address them as "Prof. Smith". Other professors explain it's because everyone is an adult and you wouldn't call your boss "Mr/Miss Smith".
It doesn't matter if you're a foreigner or a native, asking someone how they would like to be addressed is not rude or unusual. The answer will vary from person to person, some like having their title used, some like being addressed on a first name basis and (very rarely) some may prefer a nickname.
It is much better that you ask and are sure rather than being confused, and the professor (asuming they are a rational, decent human being) will understand that.
"Dear Prof. Smith - I noticed you signed your last e-mail to me, "Jim." Does that mean I should call you by your first name? Are there circumstances when that would be appropriate or inappropriate, such as with undergraduates or outside the lab?
I apologize for asking, but I'm unfamiliar with American academic protocol here.
Yours sincerely, Xxx
If a professor in a North American country presents his- or herself by his/her first name in email messages, does this mean that students can refer to him/her by his/her first name?
Only in some situations. You can be relatively certain that you can reply to his/her email and say "Hello Alice/Bob, I noticed you said X but what about Y?" . However, in a "Reply All" to that same message you can't make that assumption. You can't make the assumption about speaking to her/him in class. etc.
Or is this generally not a good idea...
Unfortunately, there is no "generally" in this matter. As others have indicated - if not absolutely certain, ask.
... unless the professor has explicitly mentioned that he/she can be referred to by first name?
It is not very likely that someone will explicitly tell you how to address him/her. Not many people make the effort to consider this finer point and actually instruct students on how to address them in different contexts. Also, it's might feel a bit vain to them to tell other people "refer to me as Professor X"; it's like you're expected to defer to them in that sense rather than have them tell you to do it. Which means it can be hard sometimes to realize what's the proper form of address (and whose propriety standard you should be adhering to).
I've noticed that most professors, who prefer to be referred to more formally, do not sign their emails with just their first names, but usually initials or first and last name.
Now that's a good indication - in the other direction. That is, if you get this kind of email, stick to "Professor X" unless told otherwise.
This depends highly on the culture (and language)
Address him as he addresses you
The most important part is not how he signed but how he addressed you.
So if he uses "Dear Mr." or whatever, use "Dear Prof.". If he uses "Hi Michael", use "Hi Simon". And so on. If he never addressed you directly, stay conservative.
Signing with his first name can happen by "incident" without thinking to much. Or because of other addressed people. It's a bad indication in general (but, of course, should be consistent with the addressing).
If there's anything to suggest the professor signed the first name out of absent-mindedness, then hold off before responding with "Hi Sally."
Otherwise, you would be okay using the first name.
However, just because you can, doesn't mean you have to.
It's always fine to ask, if you're in any doubt. One need not be an international student to ask.
For example, in office hours, you could ask, "What do you like to go by with your students?" or "What would you like me to call you?"
Make sure to notice subtle signs of possible discomfort when he or she responds to a question like this. If the results are contradictory, you'll generally be safe with a somewhat formal approach.
I am a professor at a Swiss university. I have a lab with >30 members (neurosciences) and my policy is to stay formal with my MSc/PhD students and postdocs for the first few weeks. This is because sometimes things do not work out, and I find it easier to address difficult topics (particularly the prospect of termination) if there is a certain amount of formal distance between me and my coworkers. Over time, however, I offer to everybody that we go first-names. Interestingly, I have two (Italian) postdocs who expect me to address them by first name, yet have always refused (since several years) to address me by first name. They feel uncomfortable with that, they explained to me.
A big mistake that Swiss and German students often do, however, is to address Prof Einstein in English as "Mister Einstein". Call me old-fashioned (or worse), but that really does get on my nerves. If you go formal, then please call me Dr. xy. Or else be informal and call me by first name. But if you do go formal, please address me with my academic title. Particularly if it is a title that you do not (yet) possess!
Here in the United States, in my experience modes of address in written communication are a proxy for the relative professional/social status of the individuals involved, as well as the level of familiarity in the relationship. Especially in an academic setting, the former can be somewhat hard to ascertain in some situations; the latter can be tricky, because if one party assumes too much familiarity where it's not desired by the other, awkwardness ensues.
I would break situations like that of the OP into three categories:
An undergraduate student addressing a professor.
Always address the professor as "Dr. X" or "Prof. X", unless the professor has explicitly invited you to do otherwise. Always. An undergraduate student always has inferior "professional status" to a professor, and so any sense of familiarity is pretty much irrelevant. The only exception may be if a particular student has either engaged that professor enough in office hours or in the context of a research project that the student's expertise and status has advanced to that similar to a graduate student.
A graduate student addressing a non-advisor faculty member.
Similar to #1, but the 'familiarity' aspect starts to become more important, especially as the graduate student advances along the Ph.D. program. Graduate students are on their way to becoming members of the professional research community, so their status is coming loosely in range of that of professors. Familiarity thus becomes more important, and if a student has engaged that professor in extended conversation about, e.g., course material, a first-name basis may be appropriate. In this kind of situation, if such a professor signs an email addressed specifically to the graduate student (i.e., not a general class email, for example) with his/her first name, especially on a repeated basis, then I would feel comfortable addressing the professor by first name, at least in an email. I would still hesitate a bit to address them by first name in person, at least until it seemed that no negative reaction was forthcoming from first-name address in emails.
A graduate student addressing a faculty member in a direct advisory role.
Very similar to #2, with the exception that familiarity with most advisors ends up developing quite rapidly (in my experience, at least). Thus, for all except the newest of students to the research group, as long as the professor is okay with being addressed by first name in general, the students they are advising end up calling them by first name after a very short period of time. As well, by the end of their tenure, most graduate students end up more knowledgeable about their specific research area than their advisor(s), almost completely eliminating the 'status' element of the situation.
In all of these cases, such first-name address will probably make the professor aware that the question of the propriety and/or preference in mode of address has arisen in the student's mind. Therefore, pay attention to how they sign future correspondence. If they change to "Dr. X", then stop using their first name, promptly!
I'm a professor. I have discussed this subject with many, many colleagues. Here is the consensus.
a) What to call the professor? As a rule, regardless of which country you are from or what a professor signs off on in his/her email, you should always continue addressing him/her as "Professor Lastname" in person, in email and in any other communications .... UNTIL that professor specifically asks you to do otherwise. The professor MAY ask you to call him/her something different. The professor MAY not correct you. As a default, call him/her Professor Lastname.
b) Can I ask the professor what he/she likes to be called? NO. Do not ask him/her about his/her preference. Why? Imagine that you are a medical doctor. You're been in school for many years, trained hard and despite all odds, succeeded in getting your medical degree. You of course will expect all patients, colleagues, interns, residents and others in the workplace to call you "Dr. Lastname." It would be odd for one of them to ask you if it's ok to call you something else. If you wanted to be called something else, you would probably say something.
It is the same for professors. Professors have worked many years and long hours to achieve their doctoral degrees. Addressing them by their appropriate title is the respectful and appropriate thing to do.
c) Should I really call EVERY professor "Professor Lastname"? Students tend to more frequently call professors who are not white men by their first name while calling their male, white professors "Professor Lastname". Do not fall victim to implicit bias. See point a) above. You should call EVERY professor - regardless of gender, ethnicity, nationality, etc. Trust me. They will appreciate it.