Plasticity of Mind: "Age and the Trying Out of New Ideas"

From Data Hound:

Alerted by a post on Nature News and Comment, I read with interest a newly posted paper from Mikko Packalen and Jay Bhattacharya from the National Bureau of Economic Analysis entitled "Age and the Trying Out of New Ideas."

The abstract of this working paper states:

Older scientists are often seen as less open to new ideas than younger scientists. We put this assertion to an empirical test. Using a measure of new ideas derived from the text of nearly all biomedical scientific articles published since 1946, we compare the tendency of younger and older researchers to try out new ideas in their work. We find that papers published in biomedicine by younger researchers are more likely to build on new ideas. Collaboration with a more experienced researcher matters as well. Papers with a young first author and a more experienced last author are more likely to try out newer ideas than papers published by other team configurations. Given the crucial role that the trying out of new ideas plays in the advancement of science, our results buttress the importance of funding scientific work by young researchers. (Emphasis added)

Needless to say, I was intrigued. After a quick read, I looked deeper into the methodology, particularly with regard to the highlighted terms above.

The study is based on the use of MEDLINE (accessed through PubMed). More precisely, they used “Author-ity” MEDLINE, a previously constructed version of MEDLINE with the names of authors disambiguated as much as possible. This database was used for two purposes. First, new ideas were identified by searching titles and abstracts for two- or three-word strings and associating these with the year when they first appears. Strings that subsequently occurred with high frequency were deemed to be important new ideas. The Nature commentary includes a list of the ten most frequent concepts for each decade and inspection reveals these to be sensible. Second, the "age" of each investigator was estimated by determining the year in which the first publication by this investigator appeared. Thus, this is "career age" rather than chronological age. This is a sensible approach which has both advantages and disadvantages. Most importantly, it is workable from the available data. I know from some of my recent analyses, estimating chronological ages of investigators can be quite difficult. In addition, this automatically at least partially corrects for increasing training periods over time. A disadvantage is that an early publication can "age" an investigator compared to peers....MORE