How do I learn to recognise what is worth publishing I am a PhD student starting my second year of PhD. I don't expect any major publications to come out of this within the first year or so, but I often find myself wondering if something smaller - a measurement setup, comparison of simulation techniques, etc - is worth publishing or not.

On the one hand, my Promoter says that we as a research group should publish more. I get the feeling he doesn't say this purely from a publish-or-perish perspective - rather, we spend a year or two working on something to get one big publication from the high-ranking journals, but along the way we learn a lot of little things, or come up with new tricks for measurements - all of which could be worth sending to smaller conferences or journals. 

Due to the personal self-image struggles I have, I find it very difficult to feel like my work is good or new or worth talking about most of the time. How can I improve my ability to see if something is worth sending in or not? Will this just come with experience?
Broadly, ask yourself these two questions:


Is it new?
Is it something that people in your field would want to read?


The first question is very important and sometimes disheartening. If it's not new, it doesn't matter how interesting your result is, how difficult it was to obtain, or how well you present it. You say that you have difficulty feeling like your work is new, but (unlike whether or not your work is "good") this is something that you can and should unambiguously determine by reading the existing literature. Note that "new" doesn't have to mean "earthshaking". It can (and usually does) mean more modest novelty.

The second question helps you distinguish between many possible new things to try to publish. If the paper you're working on already existed, would you and your colleagues want to read it?  You can use the degree to which the answer is "yes" to decide whether or not you should spend your time on one publication as opposed to another.

To answer either question, you need to read a lot of the existing literature, and get to know the academic community you work in. So yes, experience is important. Your advisors are there to help you when you are starting out.