How can a new PhD Student objectively evaluate how well they are doing?
The reality is that it’s impossible to evaluate how you’re doing in an entirely objective manner once you progress beyond the stage of doing problem sheets with well-defined answers. Once there’s no objective right and wrong, it becomes a question of what is valued and who assesses it. For example, people try to assess PhD students in terms of all kinds of things:


How many papers they’ve published.
Where their papers are published.
How many people have cited their papers.
How much impact they’ve had on their field.
How often they’re invited to give talks.
Where they’ve worked.
How successful their collaborations have been.
If they teach, how successful their own students are.


The reality is that all of these things measure something, to some extent. Different people will value different things, and assess them in different ways.

If you want to go into academia ultimately, and you’re asking because you want to know what the people who will assess you for academic jobs will value, a good place to look is at academic job specifications - they’re often very detailed and make it quite clear what they’re looking for. You can also ask your supervisor, who will probably be able to give you a good idea of what’s involved.

If you want to go into industry, they may be looking for very different things - again, you can find out by looking at the job specifications, and the skills of the people who work at the relevant places.

Ultimately, this is a good point in your life to realise that now you’ve moved beyond standard taught courses, you’ll never again have the same kind of “objective” outside feedback that you once did. Thus far, you’ve been optimising towards someone else’s objective function; from now on, you have to find your own. Other people can tell you what they value, or even what they think you should value, but no one can decide what you value but you.