A Latent Variable Framework for Power Estimation Within Intervention Contexts

This paper presents a latent growth SEM approach for the estimation of treatment effects, and power to detect such effects, within a true experimental design setting in which subjects are randomly assigned to treatment and control conditions. Power estimation is a critical component of intervention experiment design and the testing of their results. Although researchers have become increasingly sophisticated in applying tests for statistical significance in intervention contexts, few are aware of the power of these tests. The issues raised in this paper are not new; however, reminding researchers to consider these points is important. Exactly how the researcher handles these issues will depend on the questions asked and the resources available, as well as other considerations. Discussion underscores the relationship between the reliability of a study's measures and concomitant increases in power obtained within the SEM framework.     

C-quence: A tool for analyzing qualitative sequential data

C-quence is a software application that matches sequential patterns of qualitative data specified by the user and calculates the rate of occurrence of these patterns in a data set. Although it was designed to facilitate analyses of face-to-face interaction, it is applicable to any data set involving categorical data and sequential information. C-quence queries are constructed using a graphical user interface. The program does not limit the complexity of the sequential patterns specified by the user.     

Virtue Epistemology and Epistemic Luck

The recent movement towards virtue–theoretic treatments of epistemological concepts can be understood in terms of the desire to eliminate epistemic luck. Significantly, however, it is argued that the two main varieties of virtue epistemology are responding to different types of epistemic luck. In particular, whilst proponents of reliabilism–based virtue theories have been focusing on the problem of what I call "veritic" epistemic luck, non–reliabilism–based virtue theories have instead been concerned with a very different type of epistemic luck, what I call "reflective" epistemic luck. It is argued that, prima facie at least, both forms of epistemic luck need to be responded to by any adequate epistemological theory. The problem, however, is that one can best eliminate veritic epistemic luck by adducing a so–called safety–based epistemological theory that need not be allied to a virtue–based account, and there is no fully adequate way of eliminating reflective epistemic luck. I thus conclude that this raises a fundamental difficulty for virtue–based epistemological theories, on either construal.     

Technical note on the joint receipt of quantities of a single good

The joint receipt of x and y is the fact of receiving them both. If x and y are objects that are valued, their joint receipt is valued as well. Assumming joint receipt is a binary operation that satisfies the conditions of extensive measurement, there is a numerical representation that is additive over joint receipt. We consider the case where x and y are quantities of the same infinitely divisible good. Different sets of assumptions are explored. Invariance with respect to multiplication proves to be interesting. Invariance with respect to addition yields a linear form. A relaxation of the latter yields an approximately linear form. Finally, we consider a non-commutative but bisymmetric joint-receipt operation with a representation arising from preferences over gambles.