Which of the following is one of the trends noticed by Fred Riggs in Comparative Public Administration?

In his 1962 essay 'Trends in the Comparative Study of Public Administration', Fred W. Riggs identified three major methodological shifts in Comparative Public Administration: (1) from normative to empirical approaches, (2) from idiographic (case-by-case) to nomothetic (generalizing, law-seeking) studies, and (3) from non-ecological to ecological perspectives.