Causality description

Three major themes have been emphasized in this chapter. The first is that an effective data collection system is one of the most powerful tools available to minimize human error. Second, data collection systems must adequately address underlying causes. Merely tabulating accidents in terms of their surface similarities, or using inadequate causal descriptions such as "process worker failed to follow procedures" is not sufficient to develop effective remedial strategies. Finally, a successful data collection and incident investigation system requires an enlightened, systems oriented view of human error to be held by management, and participation and commitment from the workforce. 

Attempts to formulate a causal description of electron spin have not been completely successful. Two approaches were to model the motion on either a rigid sphere with the Pauli equation [102] as basis, or a point particle using Dirac s equation, which is pursued here no further. The methodology is nevertheless of interest and consistent with the spherical rotation model. The basic problem is to formulate a wave function in polar form E = RetS h as a spinor, by expressing each complex component in spinor form... 

Contrary to what appears at a first sight, the integral relations in Eqs. (9) and (10) are not based on causality. However, they can be related to another principle [39]. This approach of expressing a general principle by mathematical formulas can be traced to von Neumann [242] and leads in the present instance to an equation of restriction, to be derived below. According to von Neumann complete description of physical systems must contain ... 

Relationships Between Objects, Processes, and Events. Relationships can be causal, eg, if there is water in the reactor feed, then an explosion can take place. Relationships can also be stmctural, eg, a distiUation tower is a vessel containing trays that have sieves in them or relationships can be taxonomic, eg, a boiler is a type of heat exchanger. Knowledge in the form of relationships connects facts and descriptions that are already represented in some way in a system. Relational knowledge is also subject to uncertainty, especiaUy in the case of causal relationships. The representation scheme has to be able to express this uncertainty in some way. 

Sampling studies can be classified Into two types - enumeratlve, or descriptive, and analytic (j ). The classification Is Important because the applicable statistical methods and approaches are different for these two types. The objective of either type of study Is to provide a basis for action. In an enumeratlve study the action Is directed to the population from which the samples were taken. How or why the population was formed Is not of primary Interest. In an analytic study, the primary Interest Is the causal system or process which created the conditions observed In the study. Action taken Is directed toward this process rather than the population sampled. 

We realize that the information in the book is still largely descriptive and that the interdisciplinary view of the causal relationships in the rhizosphere is still in its infancy. Nevertheless, we do hope that our efforts and the high-quality scientific contributions will stimulate further interest in and work on this fascinating topic. 

Other, often made distinction in types of research, are between exploration, description, explanation, and testing, van der Zwaan (Zwaan van der, 1990). Exploration is conducted when theoretical knowledge in literature lacks information on which variables are important. Description types of research aim at the relevance of the variables. Explanation types of research aim at identifying the causal links between variables and phenomena. Finally, testing types of research aim at proving the hypotheses derived from the causal links. The research project discussed in this thesis is mainly explorative in nature. The emphasis is to design concepts and a protocol, which increases the understanding of the problem of how and why accidents continue to occur in companies in the chemical process industry. In this way a contribution to the solution of the problem will be made and consequently this research can be typified as applied positivistic exploratory research. 

Data sources contained incomplete and sometimes inaccurate incident information-for example, on numbers of injuries and community impacts. Descriptions of incidents and causal information were sometimes vague and incomplete. 

OSHA IMIS Records of workplace inspections, including those prompted by accidents where a worker is injured 1984-Present Information from OSHA field inspections, a third party More accurate description of impacts on employees and contractors Keyword indexing allows for easy search and retrieval Not comprehensive, limited to incidents selected by OSHA Inspections without abstracts cannot be keyword searched causal information unavailable Designed to assist compliance enforcement, not to report on incident causes Limited information from State-Plan states Not designed to be a lessons-leamed database... 

Whether the prediction scheme is a simple chart, a formula, or a complex numerical procedure, there are three basic elements that must be considered meteorology, source emissions, and atmospheric chemical interactions. Despite the diversity of methodologies available for relating emissions to ambient air quality, there are two basic types of models. Those based on a fundamental description of the physics and chemistry occurring in the atmosphere are classified as a priori approaches. Such methods normally incorporate a mathematical treatment of the meteorological and chemical processes and, in addition, utilize information about the distribution of source emissions. Another class of methods involves the use of a posteriori models in which empirical relationships are deduced from laboratory or atmospheric measurements. These models are usually quite simple and typically bear a close relationship to the actual data upon which they are based. The latter feature is a basic weakness. Because the models do not explicitly quantify the causal phenomena, they cannot be reliably extrapolated beyond the bounds of the data from which they were derived. As a result, a posteriori models are not ideally suited to the task of predicting the impacts of substantial changes in emissions. 

Boissieras, J. Causal Tree, Description of the Method. Princeton, NJ Rhone-Poulenc, 1983. 

The next phase of investigation involves developing a preliminary chronological description of the sequence of events that led to the failure. Timelines can be developed in various formats and levels of detail, from simple lists of events to complex sequence diagrams or causal factor charts, usually dependent upon the particular circumstances of the investigation being conducted. 

In the sort of self-deception that I shall discuss, a belief like that reported in (1) is a causal condition of a belief which contradicts it, such as (2). It is tempting, of course, to suppose that (2) entails (4), but if we allow this, we will contradict ourselves. In the attempt to give a consistent description of D inconsistent frame of mind, we might then say that since D both believes that he is not bald and believes that... 

Equation (1.3) represents a very simple model, and that simplicity derives, presumably, from the small volume of chemical space over which it appears to hold. As it is hard to imagine deriving Eq. (1.3) from the fundamental equations of quantum mechanics, it might be more descriptive to refer to it as a relationship rather than a model . That is, we make some attempt to distinguish between correlation and causality. For the moment, we will not parse the terms too closely. 

---