Much of systems analysis literature does not attempt seriously to address the problem of a lack of definition of trust, but rather only makes a passing reference to the fact that there is a discussion going on. Many papers have repeated this exact quotation of trust:
as definitive. Otherwise many studies use dictionary definitions of trust, say from Webster's definition or the Oxford English Dictionary before moving onto their problems at hand. While these strategies are legitimate as far as they go, they do not encompass the full body of work. Although the situation leaves something to be desired, some have gone so far as outright attack the situation in the research as chaos:
To address this, what follows is a simplified framework of the best conceptualizations to date.
It's not surprising the systems analysis research has failed to come to consensus on what trust means. More complete surveys (McKnight? and Chervany, 1996; Chopra and Wallace, 2003) have come to the conclusion that the social science literature has multiple definitions of trust because they each fit the particular narrow lens or perspective of their respective disciplines, and thus they are each like blind men describing an elephant. To summarize:
Which create overall three broad structural categories for conceptualizing trust:
As well a general model of how trust affects an individual, stemming from both the dictionary definitions verified with research, as trust being a) a personal feeling of the trustor, b) about how confident to be in positive expectations of the trustee, c) which induces some behavioural change in the trustor, leading Chopra and Wallace (2003) to define trust concisely as
Finally, trust has both rational cognitive and emotional affective dimensions to it, a distinction that is often grappled with in the system analysis literature (e.g. Camp, 2003). While economists look at the rational choice mechanism as a cognitive decision to trust, psychologists study how emotional states lead people to trust or distrust. McKnight? and Chervany (1996) manage to combine all these disparate views of trust in the following table:
|Affective State||Cognitive State|
|Structural||Dispositional Attitude Feeling||Expectancy Belief Intention|
Against this framework, we can place the various dimensions people have used to try to characterize trust. As Chopra and Wallace (2003) describe, with some minor changes to move displaced categorizations, plus the dimensions described by McKnight? and Chervany (1996):
Chopra and Wallace (2003) further describe that trust is developed through predictability (past experience with trustee), judgment (calculate based on available evidence), bonding (emotional relationship), reputation, and identification (do we share a common identity?). Whereas, in a later paper, McKnight? and Chervany (2001) summarize the background (hygiene) factors that are necessary to enable the process of developing trust, which are restructured here as follows:
Distrust. The latter point, social recourse, points to where trust contrasts with distrust. Trust enables higher gains while distrust avoids potential loss (Camp, 2003). Along the axis of personal, interpersonal, and structural relationships distrust is respectively a person's level of general cautiousness or wariness; the level they wish to control a particular interpersonal relationship in order to feel safe; and a mechanism (e.g. jail) to revoke trust either granted or presumed by default. One reasonable definition says distrust is the "the lack of firm belief in the competence of an entity to act dependably, securely, and reliably within a specified context." (Grandison and Sloman, 2000, p.3)
In information systems, many attempts are made to formalize trust or to model trust for the ease of implementation by machine. The following principles are commonly held:
However, although most attempts have focused on transitive trust because it was convenient for the modeling technique, without considering the full richness of how people actually use their social connections to decide trust leads to faulty systems. Consider that for one, recommendations also have to be trusted (Abdul-Rahman & Hailes, 1997a), as one may not trust their car mechanic to give medical advice, or different levels of trust in the state-run institutions of the Third World Secondly, trust is not totally transitive, but only partially transitive. If a friend recommends an accountant, it will not automatically conclude that money can be trusted with that accountant., requiring us to evaluate that accountant ourselves (Reagle, 1996). Further, trust is bound in personal relationships as described above, so until the accountant has been met and a personal relationship is built, we will not trust each other as much as the friend and the accountant. Also, people lie, are prejudiced, or have other biases that we cannot assume do not exist — even if most of the systems literature does make this simplifying assumption for the convenience of their models. This can be dangerous if the system forces a user to become vulnerable to a party that, despite what the model believes, does not get along with. Instead, a preferred model is to use recommendations to identify candidates, and then make personal judgments and build relationship from there.
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There also is a very different definition of trust: Trust is the amount of damage you allow someone else to be able to inflict to yourself. So a high level of trust doesn't mean nothing can go wrong but it means if something goes wrong it will hurt much. In this definition trust is neither a probability nor an estimation. It is measured by the part you already have exposed to your opponent.
How much someone else (or something) can inflict to yourself is (as much as you are not omnipotent) independent from yourself. I don't think you can define trust as something independent from the person that trusts. -- ZbigniewLukasiak