Abstract:      Based on the investigation data of the awardees of National Natural Science Foundation of China, we adopt event history analysis method to probe into the impact of tutor identity on Chinese front-line science researchers′ career development, as well as that of other relevant factors. Above all, we adopt Kaplan-Meier single factor analysis to inquire into the relationship between tutor identity and professional title promotion. The results of Kaplan-Meier analysis show that tutor scholarship status, tutor administration status and tutor identity type have similar effects on the professional title promotion of science researchers that they merely have a significant influence on senior title promotion, but affect the promotion of vice-senior title very little. In the meanwhile, with an advancement in tutor scholarship status, tutor administration status or tutor identity type, the survival hazard ratio of science researchers′ title promotion increases accordingly and the speed of promoting to senior title is accelerating as well. Besides, to make a further probe into the complicated connections between tutor identity and professional title promotion, the quantity of the published SCI/SSCI papers, PhD graduation college, affiliation, discipline category, postdoctoral experience, career mobility and gender are also introduced as controlled variables, and the COX proportional-hazards model for the promotion of vice-senior and senior title are constructed respectively. 
   The COX model regression analysis results are as followed: (1) Tutor identity does have a certain impact on the senior title promotion of science researchers. The survival hazard ratio of science researchers of higher tutor administration status is 29.1%, when promoting to senior title, higher than that of those of lower tutor administration status, which means that science researchers of higher tutor administration status tend to promote to senior title faster. By contrast, tutor scholar status does not affect the promotion to vice-senior title and its influence on senior title promotion is only close to but do not achieve significance, there doesn′t exist obvious promotion speed difference among science researchers with different tutor scholarship statuses. (2) Tutor identity type also has a significant influence on senior title promotion, but its impact on vice-senior title promotion is not obvious. Compared to science researchers of low scholarship-low administration type, the survival hazard ratios of those of high scholarship-high administration type, low scholarship-high administration type and high scholarship-low administration type are higher by 40.8%-52.1%. According to the hazard ratio differences mentioned above, types of tutor identity can be ranked in the following order: high scholarship-high administration type > low scholarship-high administration type > high scholarship-low administration type > low scholarship-low administration type, which means the higher the hierarchy of tutor status type is, the higher the survival hazard ratio of science researchers and the faster the speed of the promotion to senior title will be. 
   In addition, it is also showed that high-level published papers play an important role in science researchers′ title promotion, as the more high-level papers published, the faster the speed of title promotion will be, namely, scientific research ability is an elemental and essential factor for professional title promotion; compared to science researchers working in ordinary universities, science researchers working in project 985 universities have lower survival hazard ratios and slower promotion speed of senior title, their affiliation plays a negative role during the process; postdoctoral experience is beneficial to promote to senior title, science researchers with postdoctoral experience have much higher survival hazard ratios and promotion speed of senior title than those without postdoctoral experience. There exists gender difference in the promotion of professional titles, male science researchers are more likely to make it.
   Due to the limitation of sampling survey data, there are some limitations and shortcomings in the research. Firstly, as all sample data originates from the awardees of Natural Science Foundation of China who are also characterized by excellent scientific research ability, it may have negative impact on the representativeness of the conclusions of the research. Secondly, on account of the differences in the evaluation system of scientific and technological talents between China and foreign countries, it is impossible for science researchers to go back to China, after obtaining the highest degree abroad, to update identity information of their tutors effectively. Therefore, this paper fails to incorporate the relevant information of the science researchers abroad into the specific analysis. Thirdly, although professional title promotion and its speed are important indicators of science researchers′ career development, they cannot represent the whole content of career development, it should also comprise many other dimensions such as academic output, project acquisition, scientific research posts and so on.

Key words: tutor identity, science researcher, career development, event history analysis, COX proportional hazards model