How to Assess a Model's Testability and Identifiability

Formal definitions are given of the following intuitive concepts: (a) A model is quantitatively testable if its predictions are highly precise and narrow. (b) A model is identifiable if the values of its parameters can be ascertained from empirical observations. (c) A model is redundant if the values of some parameters can be deduced from others or if the values of some observables can be deduced from others. Various rules of thumb for nonredundant models are examined. The Counting Rule states that a model is quantitatively testable if and only if it has fewer parameters than observables. This rule can be safely applied only to identifiable models. If a model is unidentifiable, one must apply a generalization of the Counting Rule known as the Jacobian Rule. This rule states that a model is quantitatively testable if and only if the maximum rank (i.e., the number of linearly independent columns) of its Jacobian matrix (i.e., the matrix of partial derivatives of the function that maps parameter values to the predicted values of observables) is smaller than the number of observables. The Identifiability Rule states that a model is identifiable if and only if the maximum rank of its Jacobian matrix equals the number of parameters. The conclusions provided by these rules are only presumptive. To reach definitive conclusions, additional analyses must be performed. To illustrate the foregoing, the quantitative testability and identifiability of linear models and of discrete-state models are analyzed. Copyright 2000 Academic Press.     

First-Order Frege Theory is Undecidable

The system whose only predicate is identity, whose only nonlogical vocabulary is the abstraction operator, and whose axioms are all first-order instances of Frege's Axiom V is shown to be undecidable.     

The well-being of only children

Being an only child is generally considered to be a disadvantage. Absence of siblings is thought to involve the deprivation of critical learning experiences, while the exclusive attention of parents is said to result in overindulgence and overprotection. According to such beliefs, only children develop into selfish, maladjusted and unhappy adults. Various empirical studies have contradicted these beliefs, at least where American adults are concerned. The present study considers adolescent singletons in the Netherlands. It examines the related claims that only children have a less happy youth because they are pressed into adult thinking and behavior too early and that they stand out as "little eggheads"--good at school, but not very sportsmanlike, and unpopular among their peers. Data were gathered by means of questionnaires administered to 2,511 secondary schoolchildren. The only children in this sample neither appeared to be less happy nor was their global self-esteem any lower. The "little egghead" hypothesis was only partly confirmed. Only children feel themselves to be less proficient in sports. However, they do not consider themselves better in school or less popular among peers.     

Psychophysiological assessment of change in erotic preferences

The difficulties involved in validating effectiveness of the various therapies of anomalous erotic preferences are often underestimated. Basically, methods of physiological assessment of erotic preferences would appear to be promising. However they still pose considerable problems. There are two kinds of such methods, those where measurement of general arousal is employed, and those which are based on assessment of sexual arousal proper. The former are only weak indicators of erotic preferences; the latter are to date represented only by assessment of penile volume changes to various kinds of potentially erotic stimuli (the phallometric test). The usefulness of the latter method in assessment of (therapeutic) changes in erotic preferences is basically limited to one particular situation only.Directions are pointed out in which this test is to be further developed to make it more generally useful as an indicator of (therapeutic) change in erotic preferences.     

Integrative thinking: The essence of good medical education and practice

Integrative medicine implies the ability to extract bits of information from seemingly disparate disciplines, and synthesize them into something that is meaningful. Contemporary medical research is more apt to be driven by purely commercial incentives that not only do not favor integrative efforts, but deliberately suppress them when vested interests are threatened. Good health depends entirely on good communication whenever homeostasis is threatened. This requires a continual and instantaneous exchange of information between the constituency of the internal environment that can only be comprehended by an integrative approach. Various examples are given to illustrate these and other relevant issues.     

Minimax d-optimal designs for item response theory models

Various different item response theory (IRT) models can be used in educational and psychological measurement to analyze test data. One of the major drawbacks of these models is that efficient parameter estimation can only be achieved with very large data sets. Therefore, it is often worthwhile to search for designs of the test data that in some way will optimize the parameter estimates. The results from the statistical theory on optimal design can be applied for efficient estimation of the parameters.A major problem in finding an optimal design for IRT models is that the designs are only optimal for a given set of parameters, that is, they are locally optimal. Locally optimal designs can be constructed with a sequential design procedure. In this paper minimax designs are proposed for IRT models to overcome the problem of local optimality. Minimax designs are compared to sequentially constructed designs for the two parameter logistic model and the results show that minimax design can be nearly as efficient as sequentially constructed designs.     

APTNESS OF EMOTIONS FOR FICTIONS AND IMAGININGS

Many philosophical accounts of the emotions conceive of them as susceptible to assessments of rationality, fittingness, or some other notion of aptness. Analogous assumptions apply in cases of emotions directed at what are taken to be only fictional or only imagined. My question is whether the criteria governing the aptness of emotions we have toward what we take to be real things apply invariantly to those emotions we have toward what we take to be only fictional or imagined. I argue that what counts as a reason justifying an emotion can differ across real, fictional, and imagined domains.     

Blameworthiness as Deserved Guilt

It is often assumed that we are only blameworthy for that over which we have control. In recent years, however, several philosophers have argued that we can be blameworthy for occurrences that appear to be outside our control, such as attitudes, beliefs and omissions. This has prompted the question of why control should be a condition on blameworthiness. This paper aims at defending the control condition by developing a new conception of blameworthiness: To be blameworthy, I argue, is most fundamentally to deserve to feel guilty. Being blamed by someone else is not necessarily harmful to the wrongdoer. The blame might not be expressed, or the wrongdoer might not care. But to blame oneself necessarily involves suffering. This conception of blameworthiness explains why the control condition should obtain: We are morally blameworthy for A only if A was (directly or indirectly) under our control because (a) to be blameworthy is to deserve to feel guilty, (b) to feel guilty is to suffer, and (c) one deserves to suffer for A only if A was under one’s control.     

Familiar Words in Unfamiliar Surroundings: Davidson’s Malapropisms,Cavell’s Projections

Abstract

In their discussions and criticisms of the idea that language use is essentially a matter of following rules, Davidson and Cavell both invoke as counterexamples instances of intelligible linguistic innovation. Davidson’s favorite examples are malapropisms. Cavell focuses instead on what he calls projections. This paper clarifies some important differences between malapropisms and projections, conceived as paradigmatic forms of linguistic innovation. If malapropisms are treated as exemplary it will be natural to conclude, with Davidson, that a shared practice, be it rule-governed or not, matters only instrumentally – as something that may enhance but is neither necessary nor sufficient for successful communication. By contrast, if Cavellian projections are seen as exemplary, a shared practice will be conceived not only as essential to the possibility of meaningful linguistic innovation, but as already permeated by the sort of creativity of which projections are only particularly striking examples. It is also argued that malapropisms are not particularly convincing as counterexamples to the sort of view Davidson wants to reject. Cavellian projections, on the other hand, are powerful as counterexamples, and reflecting on the nature of their inventiveness is crucial to understanding and seeing the plausibility of Cavell’s own conception of language.     

Kinematic form and scaling: further investigations on the visual perception of lifted weight

Observers are able to judge accurately the weight lifted by another person when only the motions of reflective patches attached to the lifter's major limb joints and head can be seen (Runeson & Frykholm, 1981). What properties of these complex kinematic patterns allow judgments of weight to be made? The pattern of variation in velocity of the lifted object over position is explored as a source of information for weight: It is found to provide limited information. How are variations in kinematic patterns scaled to allow judgments of weight, a kinetic quantity? The possibility of a source of information for scaling in the kinematics is investigated. Judgments based only on patch-light displays are accurate to a degree that is improved by an extrinsic scaling basis. Finally, the sensitivity to scaling of alternative metrics used in judging is explored. Intrinsic metrics are discovered to be less sensitive to the absence of an extrinsic basis for scaling.     

Material Objects,Constitution, and Mysterianism

It is sometimes claimed that ordinary objects, such as mountains and chairs, are not material in their own right, but only in virtue of the fact that they are constituted by matter. As Fine puts it, they are “only derivatively material” (2003, 211). In this paper I argue that invoking “constitution” to account for the materiality of things that are not material in their own right explains nothing and renders the admission that these objects are indeed material completely mysterious. Although there may be metaphysical contexts in which mysterianism can be accepted with equanimity, I further argue, the question of the materiality of quotidian objects is not one of them.     

Degrees and Dimensions of Rightness: Reflections on Martin Peterson’s Dimensions of Consequentialism

Martin Peterson argues for two interesting and appealing claims: multi-dimensionalism and degrees of rightness. Multi-dimensionalism is the view that more than one factor determines whether an act is right. According to Peterson’s multi-dimensionalism, these factors are not simply ways of achieving some greater aggregate good. Degrees of rightness is the view that some actions are more wrong or less right than others without being entirely wrong. It is of course, compatible with this, that some actions are right or wrong to a maximal degree, or entirely right or wrong. Multi-dimensionalism and degrees are taken to be intertwined. On Peterson’s view, if there were only one dimension, we wouldn’t need degrees; where only one dimension applies, an act is entirely right or entirely wrong. Peterson claims that degrees of rightness or wrongness arise only because there are multi-dimensions, and that an act cannot be entirely right if it is wrong on some dimension. I shall argue against both of these claims.     

Mechanisms for precuing superiority in visual recognition

Superior recognition, when similar alternatives are studied prior to brief target pictures of common objects, is usually attributed to selective feature analysis, which is beneficial only when the target is not readily discriminable in the alternatives. The present study found equal precuing superiority, however, for similar and dissimilar alternatives with abstract geometric stimuli, and with pictures of common objects, precuing superiority occurred only when each alternative represented the same semantic category. Precuing effects did not appear when different categories were represented in the alternatives, and performance was similar to other conditions in which only a categorical match between target and alternatives was possible. These results suggest that selective feature analysis and precuing superiority only occur when the target cannot be identified by its semantic category. With dissimilar alternatives activation of the target's category can be used to select a response, and there is no benefit from precuing.     

Responsibility for believing

Many assume that we can be responsible only what is voluntary. This leads to puzzlement about our responsibility for our beliefs, since beliefs seem not to be voluntary. I argue against the initial assumption, presenting an account of responsibility and of voluntariness according to which, not only is voluntariness not required for responsibility, but the feature which renders an attitude a fundamental object of responsibility (that the attitude embodies one’s take on the world and one’s place in it) also guarantees that it could not be voluntary. It turns out, then, that, for failing to be voluntary, beliefs are a central example of the sort of thing for which we are most fundamentally responsible.     

The Question of Internationalism in Philosophy and Aesthetics

In this article aesthetics is treated purely as a branch of philosophy, and the points made are intended to apply both to philosophy more generally and aesthetics more specifically. The manner in which internationalism obviously has to do with the organization of the disciplines is discussed. Does it have any bearing on their content or substance? The distinction between organization and content is probed and seen to be much less obvious than at first sight apparent and is doubtfully tenable. Nations are foreign to philosophy in two respects. First we would remain philosophically impoverished if we attended only to the philosophy produced in our own nation. Secondly, and more interestingly, nations cannot be the subject of philosophy since they are individuals. Individuals can only be of philosophical interest in so far as they can be identified under general categories; then what matters is the category, not the individual. Philosophy, including philosophy of art, can only be interested in individuals as first-order examples or illustrations of more general second-order claims or theses. So nations must be excluded from the domain of philosophy. It does not follow that such exclusion amounts to internationalism. Indeed though internationalism itself might be a philosophical idea the dismissal of nations as philosophically irrelevant more obviously represents a commitment to universalism than to internationalism. Internationalism and universalism should not be confused though they overlap. Universalism is the ideal of the so-called enlightenment project which is defended in this paper against post-modernist criticism and also against the charge that it constitutes a view from nowhere. The view from nowhere is in the strictest sense utopian and for that reason is to be championed as a means for criticising our current assumptions and beliefs and not dismissed. Overt bias including national bias is not a problem, though the writer of philosophy must strive against it on pain of failing to write philosophy. A writer, however, can only guard against overt prejudice and bias. But a text, whether or not philosophical, is also silently exclusionary, that is, there are groups it silently excludes. At a later date the reader can often detect examples of silent exclusion. Since these silences are indefinitely many, it is always possible for a group to feel excluded. The important philosophical point is to concede the possibility of linguistic and indeed conceptual exclusion, to study its mechanisms and to consider on what principles, if any, a moral charge of exclusion is justified and when not.     

Non-Consequentialism and Universalizability

If non-consequentialists are to embrace the requirement of universalizability, then they will have to adopt a surprisingly relativistic stance. Not only will they say, in familiar vein, that the premises adduced in moral argument may only be agent-relative in force, that is, may involve the use of an indexical - as in the consideration that this or that option would advance my commitments, discharge my duty, or benefit my children - and may provide reasons only for the indexically relevant agent: in this case, me. They will also have to construe the consideration adduced in typical moral conclusions, to the effect that this or that option is right or ought to be chosen or whatever, as itself only agent-relative in force.     

Gratitude and Good Government

I attempt to show that it is notphilosophically incompetent to ground politicalobligation in feelings of gratitude. But theargument needs to be stated carefully.Gratitude must be distinguished fromreciprocity. It applies only to good governmentwhich provides benefits to citizens for whichthey ought to feel grateful. It applies only tocitizens who accept that their feelings ofgratitude are properly demonstrated by anacceptance on their part of the duties ofcitizenship. It does not apply to citizenswhose benefits are purchased at the expense ofthe unjust treatment of fellow citizens.     

Establishing partial limits on children's behavior: Use of strategic,structural, and cognitive-behavioral approaches

Abstract

Playful wrestling, splashing, fidgeting, chair-tilting, and a number of other behaviors by children often result in injuries, tantrums, or conflicts in families. Unlike most behaviors of children which can be specified by parents as acceptable or unacceptable, each of these behaviors is only partially acceptable and the limits of acceptable behavior are impossible to specify in verbal terms; these limits can only be determined by the child after the limits have been exceeded. Exact limits can be established in these instances with an intervention which integrates strategic, structural, and cognitive-behavioral approaches. Two case examples are presented and the ingredients which appear essential to the intervention are discussed.     

Clarifying the task

Those who would enquire into therelationship between “health conceptions” and “health care consequences” are faced with a formidable task. In order to make this challenge manageable it is necessary to define the scope of the task as precisely as possible. Are we, for instance, faced with a purely theoretical challenge; a task for applied philosophy, or must we employ multi-disciplinary methods? This paper argues that while philosophy has a central clarifying role, inquiry into the relationship between “health conceptions” and “health care organisation” can be done properly only through the combined efforts of several disciplines. Unless we are to be concerned only with abstract models it is essential to take account of the reality of health care situations. Given this it is suggested that the study of “health conceptions” is only a part of a greater task (unless all conceptions are to count as “health conceptions”). What is needed is understanding of the possible and actual purposes of health care, and detailed study of their practical implications.