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HUMAN, PHYSICAL. AND FISCAL RESOURCES 



125 



mately 20 percent of the nation's oceanographers; industry, about 

 10 percent; nonprofit organizations, 7 percent; and state govern- 

 ments, 4 percent. These percentages remained relatively stable 

 over time. 



The "maturity" of a discipline is the degree to which it is self- 

 perpetuating and separate from other fields. Estimating the abso- 

 lute maturity of a discipline is difficult, but examining changes in 

 a number of indicators over time can show whether a field is 

 advancing or declining. Two such indicators are the number of 

 post-doctoral fellowships awarded and the ratio of faculty posi- 

 tions that are in the form of full professorships versus assistant 

 professors. According to NSF data, the number of postdoctoral 

 positions has increased, from an estimated 20 in 1973 to 84 in 

 1989 (Figure 4-4). 



For new fields the ratio of full to assistant professors tends to 

 increase over time because of the time required for faculty promo- 

 tion and tenure, and the time universities need to establish ten- 

 ured positions. For all science and engineering fields, the ratio 

 has increased steadily over time, from 1.6 in 1973 to 2.4 in 1989 

 (Figure 4-5). The ratio for oceanography increased from 1.0 to 3.5 

 in the same period (Figure 4-5). The leap in the ratio in 1989 was 

 due to a substantial increase in the number of full professors and 

 a decrease in the number of assistant professors. The full to 



1973 1975 1977 1979 1981 1983 1985 1987 1989 



Year 

 FIGURE 4-4 Postdoctoral fellows in oceanography (NSF data). 



