Disjunctive events

They tend to overestimate the probability of conjunctive events and underestimate the probability of disjunctive events (Bar-HiUel 1973). 

Underestimation of disjunctive events Tendency to seek confirming evidence Einhoin and Hogarth 1978 ... 

It should also be mentioned that although Yablo maintains that the physical properties that realize mental properties (a posteriori) metaphysically suffice for the mental properties, he seems to take no stand on whether there is a disjunction of physical properties, all of the possible physical realizers of the mental property, which is metaphysically necessary for possession of the mental property. Suffice it to note that if there is, and if no two properties can have the same extension in every possible world, then his position collapses to Kim s position, for, then, mental properties that are determinables of physical properties will be physical properties - disjunctive physical properties. The issne, then, would be whether exemplifications of such disjunctive physical properties would he events. (See the discussion of disjunctive events later in the text.)... 

An issue that seems straightforward for counterfactual theories is whether to reject the idea that there are disjunctive events. Suppose that there is a disjunctive events or B. Suppose, further, that the nearest worlds in which — (A or B) are worlds in which — B. Then, if 4 or fi had not occurred, B would not have occurred. Yet we would not count 4 or fi as a cause of B. That, however, is no problem since B and (A or B) are not distinct events in Lewis s sense the occurrence of B implies the occurrence of A or B). There are, however, other problem cases, ones that involve distinct events. Thus, as Lewis (i986d) notes, were there disjunctive events ... 

Evaluation of conjunctive and disjunctive events Conjnnctive events have a linear quality, such as the completion of an undertaking (e.g., tasks in a project life cycle). For the undertaking to succeed, each of a series of events must occur. Even when each of these events is very likely, the overall probability of success can be quite low if the number of events is large. The general tendency of a decision maker to overestimate the probability of conjunctive events leads to unwarranted optimism in the evalnation of the likelihood that a plan will succeed or that a project will be completed on time. 

Disjunctive events are typically encountered in the evalnation of risks. A complex system, such as a nuclear reactor or a human body, will malfunction if any of its essential components fails. Even when the likelihood of failure in each component is slight, the probability of an overall failure can be high if many components are involved. Because of anchoring, decision makers underestimate the probabilities of failure in complex systems. 

An emergent field dealing with the physical/chemical processes that underlie the changes of lipid phase state during such cellular events as membrane fusion, vesicle trafficking, and cell disjunction. 

Wide intercontinental and disjunct ranges could also have been created either by many long-distance (e.g. intercontinental) events, or few long-distance but a lot of dispersal over medium or short distances founding intermediate populations... 

The universal set Q, which contains all conceivable events, is called the certain event, its complement 2 the impossible event. Two events for which A n B = 0 is true, are called incompatible or disjunct, where 0 denotes the empty set. 

I am willing to believe that physics is general in the seme that it implies that any event which consists of a monetary exchange (hence any event which falls under Greshams Law) has a true description in the vocabulary of physics and in virtue of which it falls under the laws of physics. But banal considerations suggest that a description which covers all such events must be wildly disjunctive... What are the chances that a disjunction of physical predicates which covers all these events. .. expresses a physical natural kind In particular, what are the chances that such a predicate forms the antecedent or consequent of some proper law of physics [Emphases original]... 

If we embrace an abundant conception of properties, then there is a substantive question of which properties are such that they are constitutive properties of events. For example, if disjunction is a property-forming operation, and so there are disjunctive properties, it by no means follows that disjunctive properties can be constitutive properties of events. Also, even if complementation is a property-forming operation, and so there are negative properties, it is a nontrivial question whether negative properties can be constitutive properties of events — whether, that is, omissions are events. 1 will recur to these matters later. The point to note for now is that on an abundant conception of properties, no extant property exemplification account of events counts literally every property as such that it can be a constitutive (or essential) property of an event. One might embrace quantification as a property-forming operation but reject it as an eventforming operation and so reject the claim that functional properties can be constitutive properties of events. Whether functional properties can be constitutive properties of events, and so whether there are functional events in the sense in question, is a controversial issue. The issue, moreover, as I see, is inseparable from the issue of whether such entities would be causes. 

Even if there are disjunctive properties, there seems good reason to deny that they are constitutive properties of events. It should be noted that functional properties will be nomologically coextensive with the disjunction of their (actual world) realizing properties. In defending the view that events can have functional properties as constitutive properties yet lack disjunctive properties as constitutive properties, NRP theorists would be committed to the view that two properties can be nomologically coextensive yet the one be a constitutive property of an event and the other not. 

The model proposed here combines the present-day geomorphological configuration of the extensive and mostly continuous crystalline surface with discontinuous areas of sedimentary surfaces. As such, it would also provide an explanation of the disjunct distribution of the species inhabiting sandy areas, as being a consequence of the events promoting vicariance within a formerly... 

To hide detailed failure propagation paths (req.3), the CFT is transformed into a form that is independent of the original structure of the tree. For this purpose, different forms could be used, but the best known form of coherent fault trees are minimal cut sets (MCS). The MCS of a fault tree are the sets of basic events (internal and input failure modes), where every event must be true for the top event to become true. MCS are used for qualitative analyses of fault trees They show only the minimal failure combinations and abstract from the structure and the failure paths of the free. Because MCS are only applicable for coherent fault trees, prime imphcants (PI) have to be used for non-coherent ones, since these also include negated literals (variables). MCS/PI show the fault tree in its minimal disjunctive normal form (DNF), which is independent of the original structure of the tree, but mathematically equivalent. Other normal forms could also be used for abstracting from the structure, but MCS and PI are the most appropriate and proven ones for fault trees. Additionally, MCS and PI... 

Suppose there are n distinct components 03,, ...,and let T be the fault tree with basic events of only covered component failures (i.e., with perfect fault coverage), T can be defined as a disjunction of T and the disjimction of all the imcovered component failures [4, 5], i.e.,... 

Thus, the direction of the anchoring bias can sometimes be inferred from the structure of the event. The chain-like structure of conjunctions leads to overestimation, and the funnel-like structure of disjunctions leads to underestimation. 

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