Is it safe for a student to give negative feedback in student evaluations?

I feel there are two different layers to that - whether, and to what extent, teaching evaluations are actually anonymous, and if they aren't, whether it's still "safe" to give a bad one.

Are evaluations anonymous?

On a superficial level, all universities that I have taught at had entirely anonymous evaluations. At no point in the process was I ever told which student gave which feedback. However, in a small class (say 10 students or less), anonymous evaluations aren't really all that anonymous - in such classes, I often have at least an educated guess which student wrote which evaluation. In a larger class I usually have no idea which student wrote which comment - there are usually groups of students with similar concerns and troubles, and I also don't know individual students nearly well enough at the end of a 100-students class to divine which student may have written what.

Yet, even in large classes sometimes a teacher may have a hunch which student wrote a specific comment, if the raised concern or the way of expression is sufficiently unique. For instance, in one of my introductory classes last year, one student was struggling extraordinarily and it was clear that he was working all the time on this course to pass (which he ultimately did). When evaluations came in and one student remarked on the almost unsurmountable workload it's easy to at least suspect that this was this student.

In short, relying on anonymity alone may be a dangerous game. If I were giving some really negative feedback I would try to keep it general enough that at least a handful of students could have written the same comment.

Is it safe to give a negative evaluation (assuming it's not, or at least not completely, anonymous)?

Clearly, teachers are supposed not to retaliate upon receiving a bad evaluation, and I expect the large majority of teachers in a reputable university will not. However, professors also being humans, a subconscious bias may still taint further interactions. I guess it depends on what you mean with "safe" - there is no 100% certainty that a negative evaluation will not backfire on you, but by and large I can tell you that many students give negative evaluations in all schools I have been at, and as far as I can tell nothing bad really happens to them.

Anything else?

It's not really your question, but in my experience it is almost universally a good idea to try hard to phrase negative evaluations in the same way as you would also do when giving feedback face-to-face (that is to say: fair, polite, without unnecessary superlatives, and if possible strengthened by data). Ultimately you probably want your feedback to be heard / integrated into the next course iteration, and the less a teacher is annoyed by your comments, the larger the chance that they will actually consider them. If you want to use evaluations to vent, this is certainly your right - but you should be aware that your evaluation will then have virtually no impact on the course design.

There is no straightforward answer to this, since it varies enormously by institution.

Anonymous feedback can still be unmasked

As others have said already, an ostensibly anonymous survey may not end up being so anonymous in practice; it is pretty easy to guess someone's identity, especially if the class is small or if you have interacted with the lecturer on a one-to-one basis.

So, avoid ad hominem attacks -- be specific about the problem, and avoid assigning blame

Nonetheless, you can and should make negative comments where they are warranted. Ensure your comments are detailed (as a tutor and lecturer, there is nothing more irritating than getting a negative evaluation without any explanation of why) and constructive. Try not to assign blame to a specific person unless you are absolutely sure it is his/her fault. Do not make ad hominem attacks, but focus on the issues in an impersonal manner. Examples may include:

• "I had difficulty keeping up with the pace of the lectures";
• "not enough opportunities to discuss the assignment";
• "course content was too superficial, and failed to analyse issues in sufficient depth, meaning that I felt unprepared for the demands of the assignment";
• "the selection of case studies across the lectures seemed incoherent -- the lecturer did not make clear how they were connected to the topic";
• "the lecturer spent most of the time regurgitating feminist readings uncritically, and refused to engage with questions from students who disagreed";
• "AV facilities were so unreliable that a lot of time was wasted getting the video and sound clips to work".

Negative comments can be useful in enabling the lecturer to make a case to higher authorities for more time/resources

In many cases, a lecturer may not have that much control over the course he/she teaches, or may be forced to make compromises on content/resources/hours/&c. As a result, a reasoned negative comment may, in fact, be very useful in that it helps the lecturer decide how to prioritise in future (e.g.: should he/she give more contact hours in larger classes or less hours but in smaller groups?). It also provides ammunition for the lecturer to make a case to higher authorities for more resources -- here are some examples of hypothetical things a lecturer might say to the head of department with your help:

• "I think eight lectures is not enough time to get through the syllabus -- in last year's evaluations, lots of students said they had trouble understanding the material and felt that the lectures were too fast.";

• "My remit is to critically examine feminist, Marxist, and nihilist readings of late-nineteenth-century Russian literature. However, this is impossible to achieve in the three one-hour lectures I am allotted, so I tried to discuss one approach in more depth, in the hope that this would encourage students to explore the other two in the same way. Unfortunately, as the student evaluations make clear, this strategy did not work: many students felt short-changed because I spent only half a lecture on Marxism and the other half on nihilism, and complained that my two lectures on feminism amounted to propaganda.";

• "The situation with room bookings was a complete shambles last semester. There were too many last-minute room changes, which turned my classes into cross-campus games of tag. Several students said that they missed lectures because they could not find the correct room. I also had several more evaluations complaining about the disruption of so many people turning up late.";

• "Since we lost our dedicated AV technician in last year's restructure, I have found it very difficult to get the technology to work reliably in my lectures. As you can see from the student evaluations, they were frustrated by the amount of time wasted getting the sound system to work.";

• "Since the number of teaching assistants on the course was cut from three to one, student satisfaction has dipped considerably. Before this cut, almost everyone was satisfied with the availability of feedback on their work. This year, a lot of students complained about a shortage of office hours and lack of individual feedback. I realise that having more teaching assistants is expensive, but the student feedback shows we need them.";

• "I am finding it very difficult to teach according to the textbook prescribed by the department for this course -- the textbook covers only about half the necessary material. I have spent countless office hours going over misconceptions from the textbook, and many of the student evaluations say that the textbook does not explain things clearly and assumes a lot of prior knowledge that they do not have.";
• "I have strong qualms about teaching the course on theatre in ancient Greece again. As you know, this is not my area of expertise by any stretch, and, as last year's student evaluations show, my lack of expertise was painfully evident.".

I will only supplement the great answer of xLetix here.

Let me note that the more radical and extreme your statements in an evaluation the less likely it will be that it is acted upon. If you have serious, negative, things to say, then another venue will probably be more effective, though it is unlikely to be anonymous.

I think that extreme comments are easy to ignore, both by the faculty member and by the institution. However, if a number of students say things that are similar, then they will be taken note of. They don't need to be very negative to be effective and to initiate change. "I wish the instructor had assigned more/fewer exercises", if said by three or four students is better than one person saying something over the top.

My experience with (anonymous) evaluations was that they were helpful, but mostly confirmed things I already knew. There were few surprises. The extreme ones might come from those who were malcontented generally, or who didn't want to put in the effort to learn and believed I could make their learning "automatic" in some way.

But sometimes we slip up in a course and it is noticed and commented on. If stated properly, then it can generate self reflection that helps us improve.

I've also had experience with public evaluations, though still anonymous (via an anonymous wiki or rate my professor). With such a system anyone can say publicly whatever they want and if it is unsupported by the other students they will be likely to say so. I never found it necessary to reply to attacks or to defend myself, since it was clear that the complaint was an outlier. But if other students agree, then you have some work to do.