The functional method is a new test theory using a new scoring method that assumes complexity in test structure, and thus takes into account every correlation between factors and items. The main specificity of the functional method is to model test scores by multiple regression instead of estimating them by using simplistic sums of points. In order to proceed, the functional method requires the creation of hyperspherical measurement space, in which item responses are expressed by their correlation with orthogonal factors. This method has three main qualities. First, measures are expressed in the absolute metric of correlations; therefore, items, scales and persons are expressed in the same measurement space using the same single metric. Second, factors are systematically orthogonal and without errors, which is optimal in order to predict other outcomes. Such predictions can be performed to estimate how one would answer to other tests, or even to model one's response strategy if it was perfectly coherent. Third, the functional method provides measures of individuals' response validity (i.e., control indices). Herein, we propose a standard procedure in order to identify whether test results are interpretable and to exclude invalid results caused by various response biases based on control indices.Keywords: functional method, exploratory factor analysis, psychometrics, response reliability, response validity, self-rated questionnaires IntroductionFor about a century, psychological testing has become an important aspect of psychologists' activity with an ever-growing importance. Nonetheless, despite formidable developments in psychometrics during the last several decades, most clinical and scientific practices covering psychological assessment continue to refer to the nearly unchanged method inherited from classic test theory (CTT). Many critics have been raised against the classic method: In particular, it is too often assumed that items have no second loadings, and that each item has the same weight, which is optimal for confirmatory factor analysis, but it also leads to a loss in reliability. Furthermore, though CTT assumes requirements in test validity (e.g., satisfactory reliability, concurrent validity), few requirements have been formulated concerning individuals' ways of responding to self-administered questionnaires.The functional method is a new method that improves test reliability and provides indices of one's response validity to self-administered tests. First, three major issues of classic testing are Dupuis et al. Introduction to the functional method examined; then item response theory (IRT) is presented as the main alternative to CTT. Last, the functional method is presented with a focus on how it deals with these problems and compared with CTT and IRT. The Problem of Response Intrinsic QualityIt is well known that psychological tests can be biased both intentionally and unintentionally; this can invalidate one's test results, but can even invalidate an entire test validation (Caldwell-Andrews et...
Bio-opticaI measurements were carried out on eutrophic Lake Zug and oligotrophic Lake Lucerne, to provide data and models for the in situ calibration of multispectral imagery collected in 1991, during an AVIRIS flight over Central Switzerland.The results indicate that Secchi depth, chlorophyll and total suspended solid concentrations, vertical extinction coefficient, absorption coefficient and irradiance reflectance in the PAR region can be used to discriminate between the two lakes. Dissolved organics concentration, scattering and total attenuation coefficients estimates, as well as backscattering probability, are less acceptable, because of instrumental limitations.Relationships between optical and water quality parameters were investigated and found to behave according to accepted theoretical frameworks. Both lakes exhibited vertical and horizontal heterogeneities in chlorophyll and turbidity, and had contrasting mean bio-optical characteristics: although suspended solid concentrations were similar, transparency was lower in Lake Zug, but reflectance was substantially higher in Lake Lucerne. Water colour determined by chromaticity analysis was blue-green in Lake Lucerne and green in Lake Zug.Reflectance spectra simulated through a three-component optochemical model did not completely match those derived from in situ measurements, because of lack of site-specific optical cross-sections for suspended minerals and dissolved organics.The monitoring of water quality in subalpine lakes by remote sensing, both with present and future technology, is discussed and considered as possible, provided that their optical behaviour is known, and preferably expressed by a valid optochemical model.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.