Collaboration is believed to be influential on researchers' productivity. However, the impact of collaboration relies on latent factors such as disciplines, collaboration patterns, and collaborators' characters. Moreover, at different career stages, such as the novice stage, the experienced stage, etc., collaboration is different in scale and breadth, and its effect on productivity varies. In this paper, we study collaborative relationships in four disciplines, Organic Chemistry, Virology, Mathematics and Computer Science. We find that the productivity is correlated with collaboration in general, but the correlation could be positive or negative on the basis of which aspect of collaboration to measure, the collaboration scale or scope. The correlation becomes stronger as individual scientists progress through various stages of their career. Furthermore, experimental disciplines, such as Organic Chemistry and Virology, have shown stronger correlation coefficients than theoretical ones such as Mathematics and Computer Science.