In stock analysis the baseline for alpha is 0, however for beta it's 1. Why is that so, if they are both comparisons to the market at a large?
I believe that you are working with the CAPM there. Alpha is a measure of how much excess return e.g. a stock generates, while Beta is a measure of how volatile its price is relative to the market. So the "baseline" or market does obviously have a beta of one with an Alpha of zero (no excess return since you are looking at the market/"baseline" as you called it), according to the CAPM.
I hope this answers your question.