Comparison of methods for estimating premorbid intelligence

To evaluate impact of neurological injury on cognitive performance it is typically necessary to derive a baseline (or ‘premorbid’) estimate of a patient’s general cognitive ability prior to the onset of impairment. In this paper, we consider a range of common methods for producing this estimate, including those based on current best performance, embedded ‘hold/no hold’ tests, demographic information, and word reading ability. Ninety-two neurologically healthy adult participants were assessed on the full Wechsler Adult Intelligence Scale – Fourth Edition (WAIS-IV; Wechsler, 2008) and on two widely used word reading tests: National Adult Reading Test (NART; Nelson, 1982; Nelson & Willison, 1991) and Wechsler Test of Adult Reading (WTAR; Wechsler, 2001). Our findings indicate that reading tests provide the most reliable and precise estimates of WAIS-IV full-scale IQ, although the addition of demographic data provides modest improvement. Nevertheless, we observed considerable variability in correlations between NART/WTAR scores and individual WAIS-IV indices, which indicated particular usefulness in estimating more crystallised premorbid abilities (as represented by the verbal comprehension and general ability indices) relative to fluid abilities (working memory and perceptual reasoning indices). We discuss and encourage the development of new methods for improving premorbid estimates of cognitive abilities in neurological patients

A genetic algorithm to find optimal reading test word subsets for estimating full-scale IQ

In clinical neuropsychology the cognitive abilities of neurological patients are commonly estimated using well-established paper-based tests. Typically, scores on some tests remain relatively well preserved, whilst others exhibit a significant and disproportionate decline. Scores on those tests that measure preserved cognitive functions (so-called ‘hold’ tests) may be used to estimate premorbid abilities, including scores in non-hold tests that would have been expected prior to the onset of cognitive impairment. Many hold tests entail word reading, with each word being graded as correctly or incorrectly pronounced. Inevitably, such tests are likely to contain words that provide little or no diagnostic power (i.e., can be eliminated without negatively affecting prediction accuracy). In this paper, a genetic algorithm is developed and demonstrated, using n=92 neurologically healthy participants, to identify optimal word subsets from the National Adult Reading Test that minimize the mean error in predicting the most widely used clinical measure of IQ and cognitive ability, the Wechsler Adult Intelligence Scale Fourth Edition IQ. In addition to requiring only 17-20 of the original 50 words (suggesting that this test could be revised to be up to 66% shorter) and minimizing mean prediction error, the algorithm increases the proportion of the variance in the predicted variable explained in comparison to using all words (from r^2 = 0.46 to r^2 = 0.61). In a clinical setting this would improve estimates of premorbid cognitive function and, if an abbreviated revision to this test were to be adopted, reduce the arduousness of the test for patients. The proposed method is evaluated with jackknifing and leave one out cross validation. The general approach may be used to optimize the relationship between any two psychological tests by finding the question subset in one test that minimizes the prediction error in a second test by training the genetic algorithm using data collected from participants upon whom both tests have been administered. This approach may also be used to develop new predictive tests, since it provides a method to identify an optimal subset of a set of candidate questions (for which empirical data have been collected) that maximizes prediction accuracy and the proportion of variance in the predicted variable that can be explained

The robustness of preferences during a crisis: The case of COVID-19

We investigate how preferences have been affected by exposure to the COVID-19 crisis. Our main contributions are: first, our participant pool consists of a large general population sample; second, we elicited a wide range of preferences (risk, time, ambiguity, and social preferences) using different incentivized experimental tasks; third, we elicited preferences before the onset of the crises and in three additional waves during the crises over a time period of more than a year, allowing us to investigate both short-term and medium-term preference responses; fourth, besides the measurement of causal effects of the crisis, we also analyze within each wave during the crisis, how differential exposure to the crisis in the health and financial domain affects preferences. We find that preferences remain remarkably stable during the crisis. Comparing them before the start and during the crisis, we do not observe robust differences in any of the elicited preferences. Moreover, individual differences in the exposure to the crisis at best show only weak effects in the financial domain

Підвищення ефективності теплопостачання при врахуванні температурно-погодних факторів

In this paper we will address the questions of what and where the value of open access to research data might be and how libraries and related stakeholders can contribute to achieve the benefits of freely sharing data. In particular, the emphasis is on how libraries need to acquire the competence for collaboration to train and encourage researchers and library staff to work with open data. The paper is based on the early results of the RECODE project, an EU FP7 project that addresses the drivers and barriers in developing open access to research data in Europe (http://www.recodeproject.eu)

The no-defect conjecture in cosmic crystallography

The topology of space is usually assumed simply connected, but could be multi-connected. We review in the latter case the possibility that topological defects arising at high energy phase transitions might still be present and find that either they are very unlikely to form at all, or space is effectively simply connected on scales up to the horizon size.Comment: LaTeX-REVTeX, 5 pages and 2 figures uuencoded, submitted to Phys. Rev. Let

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