I have seen quite a few students editing the Wikipedia page of their advisors. I wonder what the view of the academic community are on this. There might be some conflict of interest since promoting one's advisor can be seen as indirectly promoting oneself, but at the same time it can be argued that a student (especially graduate student) may have a decent amount of knowledge about his advisor.
It is not ethical, and is, per Wikipedia guidelines, a conflict of interest.
If you have a personal connection to a topic or person, you are advised to refrain from editing those articles directly, from adding related advertising links, links to personal websites and similar, and to provide full disclosure of the connection if you comment about the article on talk pages or in other discussions.
There is an exception. For example, let's say Dr. Potato is listed as a life-long sprout, when he is actually a tuber.
An exception to editing an article about yourself or someone you know is made if the article contains defamation or a serious error that needs to be corrected quickly. If you do make such an edit, follow it up with an email to WP:OTRS, Wikipedia's volunteer response team, or ask for help on WP:BLPN, our noticeboard for articles about living persons.
Other examples of non-controversial edits would be like fixing spelling and grammar errors, or linking to an article on Wikipedia that may be missed.
It is also encouraged that, instead of providing edits and information, you provide:
Those with a potential conflict of interest are encouraged to upload good-quality digital media files that are appropriately licensed for Wikipedia and that improve our coverage of a subject.
Images and media that are non-controversial can then be used by others to be cited, as they wouldn't express an opinion.
Examples of non-controversial stuff would be like a picture of the person, preferably doing nothing controversial.
According to Wikipedia's policies, a living person or their representatives (which would include a student, because the student could reasonably be seen in this way by others), are permitted but discouraged from editing that person's article. Obvious gaps or errors can be addressed, but since it is difficult to maintain a neutral point of view, the suggested procedure is for the subject of an article to put material into its talk page instead, where others can decide on notability. I think that this would be the appropriate route for a student as well.
There is a lot of discussion and ambiguous or conflicting advice in Wikipedia about so called conflict of interest (COI) editing. COI editing is any editing by article subjects, or those closely associated with them. The situation you describe sounds like it will usually qualify.
Fundamentally, the ambiguity stems from the fact that COI editing is not necessarily a problem itself but that it very frequently leads to problematic behavior and contributions. The most frequent problems with COI editing are with Wikipedia's neutral point of view policy (NPOV). Violations of this would be a breathless or non-encyclopedic tone, inclusion of details that are trivial or unencyclopedic, or in the most problematic case, systematic removal of material that is critical of the subject.
Because these problems are hard to avoid for people without distance to the subject, and because COI editing can call into question the neutrality of the encyclopedia in general, COI editing is not forbidden but is generally discouraged — especially from new editors who are not familiar with Wikipedia's policies and experienced.
There are other problems as well. For example, conflicted editors might create articles for subjects that don't satisfy Wikipedia's notability policy (or Wikipedia's notability policy for academics) because these determinations are inherently subjective and editors close to the subjects are not neutral arbiters.
It's a tricky balance because, on the other hand, Wikipedia does not want to prohibit editing by everybody with the most expertise about the subject. That said, my advice is that if someone is new to Wikipedia editing, they should avoid COI editing and/or try to focus on the types of uncontroversial edits explicitly allowed by the COI policy like typo fixes, references, categorization, etc. If a connected contributor wants to make a potentially controversial improvement, they should always raise it on the talk page of the article first and ask other non-conflicted editors to make the change. Creating new articles about a subject to which you have a connection is also discouraged.
Finally, revealing the presence of a COI is recommended but not required. Moreover, it is against Wikipedia policy to reveal the identity of an editor against their wishes even if it reveals a conflict of interest. Doing so is a violation of Wikipedia's harassment policy.
Besides the obvious issues of conflict of interest, Wikipedia also considers original research improper as it leaves no external source to cite. If you include a fact about something in a Wikipedia article based on your personal experience, there's no way for other editors to verify it.
So including information about a professor based purely on knowing that professor yourself is a violation of the No Original Research policy. This isn't an inherent problem as students can certainly be careful to cite sources for the information they add but it is important to keep in mind when writing about a subject you are closely familiar with.
The other answers to date seem to be focussed on what Wikipedia says about the ethics of this action. But you do not owe anything to the biased, rotten edifice that is Wikipedia (in fact, I sometimes add a few bits of deliberately false information to Wikipedia articles, so that I can quickly spot when undergraduates have relied on Wikipedia instead of checking the literature!), so my answer will focus on the ethical issues of publishing information about a colleague/superior on the world wide web.
First, it is really important that you do not add confidential information about the subject, unless you are entitled to do so or have permission to make it public -- in particular, do not disclose anything about:
- his/her family (some people do splash photographs of their children all over the place, but others prefer to keep even the existence of any children secret -- whatever your views on this, it is not your place to decide on someone else's behalf which course of action is right for him/her);
- a "protected characteristic" (exact definition varies by jurisdiction, but this would usually encompass religion, sexuality, marital status, race, disabilities, medical history), unless the information is already published with the consent of the subject on a www page accessible to anyone (again, whilst some people will talk very openly and publicly about "protected characteristics", others do not want anybody to know about them, often for very good reasons -- for example, if you are looking for a job or applying for a big grant, you might not want anybody knowing that you have just recovered from a serious illness or are about to get married).
Accessibility vs discoverability
Secondly, keep in mind the difference between accessibility and discoverability. For example, it may be possible to access someone's address or date of birth on the internet (in the UK, if someone has ever been a company director, such data are likely to be available via the Companies House online register), that does not make it a good idea to publish such data on a highly discoverable website such as Wikipedia.
Not distracting unduly from the public persona the subject wishes to cultivate
Thirdly, you should probably refrain from writing anything that is unrepresentative of the subject's professional life, or likely to cause the subject significant embarrassment/distress, unless there is a strong public interest. You are under no obligation to care how Wikipedia feels about anything, but you should consider the feelings of the subject, since a Wikipedia biography is likely to have a significant bearing on his/her reputation. If a subject is notable for one thing (e.g.: a controversial article; being the victim of a notable crime; campaigning on a social/political issue), you should ensure that any coverage on a highly discoverable site also gives a balanced overview of his/her professional profile overall. A Wikipedia article is likely to be very near the top of a search engine's results, and may well end up higher than an official university profile page. From the subject's perspective, writing an article about the big notable thing will make the professional persona he/she wants to convey less discoverable, and may result in less attention going to the great research/teaching he/she is doing.