Sammenlign metoder

	Reference Publication Year Spectroscopy (RPYS)	Main Path Analysis
Fagfelt	Bibliometri	Bibliometri
Familie	Process / pipeline	Process / pipeline
Opprinnelsesår	2014	1989
Opphavsperson	Werner Marx, Lutz Bornmann, Andreas Barth & Loet Leydesdorff	Norman P. Hummon & Patrick Doreian
Type	Cited-reference temporal analysis pipeline for historical roots	Citation-network traversal pipeline for knowledge trajectories
Opprinnelig kilde	Marx, W., Bornmann, L., Barth, A., & Leydesdorff, L. (2014). Detecting the historical roots of research fields by reference publication year spectroscopy (RPYS). Journal of the Association for Information Science and Technology, 65(4), 751-764.	Hummon, N. P., & Doreian, P. (1989). Connectivity in a citation network: The development of DNA theory. Social Networks, 11(1), 39-63.
Alias	RPYS, Cited-Reference Spectroscopy, Historical Roots Detection	MPA, Citation Main Path Analysis, Knowledge Flow Path Analysis
Relaterte	3	3
Sammendrag	Reference publication year spectroscopy (RPYS) detects the historical roots of a research field by analyzing not the field's own publications but the publication years of the works those publications cite. Introduced by Werner Marx, Lutz Bornmann, Andreas Barth, and Loet Leydesdorff in 2014, RPYS aggregates all cited references across a corpus, counts how many reference the literature of each past year, and plots the resulting spectrum. Seminal works leave a distinctive mark: the years in which they appeared show up as sharp peaks rising above the smooth background of routine citation. By detecting these peaks — using the deviation of each year's count from a running median — and then inspecting which highly cited references produced them, RPYS pinpoints the foundational papers and books on which a field was built, providing a quantitative, citation-based historiography.	Main path analysis (MPA) traces the principal trajectory of knowledge development through a citation network. Introduced by Norman Hummon and Patrick Doreian in their 1989 study of the discovery of DNA, the method treats a field's literature as a directed acyclic graph in which documents point backward in time to the work they cite. Rather than mapping the whole network, MPA weights each citation link by how central it is to the flow of ideas — how many knowledge-carrying paths run through it — and then extracts the chain of most-traversed links from the field's earliest sources to its most recent sinks. The result is a compact 'main path': an ordered sequence of papers that represents the backbone along which a research front actually developed.