L'indiviualizzazione come decisione

Abstract

Nelle scienze forensi e discipline affini, ricercatori e professionisti continuano ad essere divisi —da un punto di vista intuitivo e concettuale —sul significato della nozione di ‘individualizzazione’, quel processo tramite il quale un insieme di soggetti potenzialmente all’origine di una traccia èridotto ad un singolo individuo. In particolare, le recenti inversioni di tendenza promotrici di un’interpretazione dell’individualizzazione come decisione si sonorivelate un semplice cambio di etichetta [1], lasciando irrisolti aspetti di natura concettuale e teorica. Va inoltre detto che sia organizzazioni professionali che professionisti preferiscono astenersi dallo sposare la nozione di decisione nei termini di un approccio decisionale formale all’interno del quale l’individualizzazione puòessere concettualizzata in maniera adeguata. Questo atteggiamento è dovuto in modo particolare alle difficoltàinsite nel misurare la desiderabilitào indesiderabilitàdelle conseguenze di una decisione (p. es. usando le funzioni di utilità). Questo articolo presenta e discute i concetti fondamentali di utilitàe perdita, con particolare attenzione alla loro applicazione all’individualizzazione in campo forense. L’articolo, per un verso, sottolinea come un apprezzamento adeguato del quadro teorico possa semplificare i compiti necessari all’applicazione della teoria bayesiana della decisione e, per l’altro, dimostra come detta teoria possa essere applicata in maniera proficua a problemi concreti. Si dimostra che se si vogliono apportare cambiamenti alle scienze forensi che non siano meri cambi di etichetta, concepire l’individualizzazione come decisione richiede l’apprezzamento del quadro teorico sottostante.

Throughout forensic science and adjacent branches, academic researchers and practitioners continue to diverge in their perception and understanding of the notion of ‘individualization’, that is the claim to reduce a pool of potential donors of a forensic trace to a single source. In particular, recent shifts to refer to the practice of individualization as a decision have been revealed as being a mere change of label [1], leaving fundamental changes in thought and understanding still pending. What is more, professional associations and practitioners shy away from embracing the notion of decision in terms of the formal theory of decision in which individualization may be framed, mainly because of difficulties to deal with the measurement of desirability or undesirability of the consequences of decisions (e.g., using utility functions). Building on existing research in the area, this paper presents and discusses fundamental concepts of utilities and losses with particular reference to their application to forensic individualization. The paper emphasizes that a proper appreciation of decision tools not only reduces the number of individual assignments that the application of decision theory requires, but also shows how such assignments can be meaningfully related to constituting features of the real-world decision problem to which the theory is applied. It is argued that the decisonalization of individualization requires such fundamental insight to initiate changes in the fields’ underlying understandings, not merely in their label. 

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