Can Design Choices for Language-Based Editors be Analysed with Keystroke-Level Models?

We have been concerned for some time with the lack of rigorous experimental evaluation of design options chosen for tools used by software engineers. In a series of studies using various evaluation techniques we built Keystroke-Level Models and conducted an empirical usability study of a design issue (choice of editing paradigm for language-based editors) that has reached a `subjective stalemate' in the research community. The KLM analysis enabled us to predict usage differences and while this was useful we also noticed several problems, in particular we were concerned about the estimated value and placement of the memory operator. By utilising the same tasks in the usability study as in the KLM analysis, we were able to compare results from both evaluations and effectively validate the overall KLM estimates and the specific operator values involved. KEYWORDS: Keystroke-Level Model, model validation, language-based editors 1 Introduction Two basic paradigms for editing are commonly ..

Nuclear Spins and Magnetic Moments of Cu-71,Cu-73,Cu-75: Inversion of pi 2p(3/2) and pi 1f(5/2) Levels in Cu-75

We report the first confirmation of the predicted inversion between the pi 2p(3/2) and pi 1f(5/2) nuclear states in the nu g(9/2) midshell. This was achieved at the ISOLDE facility, by using a combination of in-source laser spectroscopy and collinear laser spectroscopy on the ground states of Cu-71,Cu-73,Cu-75, which measured the nuclear spin and magnetic moments. The obtained values are mu(Cu-71)=+2.2747(8)mu(N), mu(Cu-73)=+1.7426(8)mu(N), and mu(Cu-75)=+1.0062(13)mu(N) corresponding to spins I=3/2 for Cu-71,Cu-73 and I=5/2 for Cu-75. The results are in fair agreement with large-scale shell-model calculations.status: publishe