An overview of applied robust methods

Data in social sciences are typically non-normally distributed and characterized by heavy tails. However, most widely used methods in social sciences are still based on the analyses of sample means and sample covariances. While these conventional methods continue to be used to address new substantive issues, conclusions reached can be inaccurate or misleading. Although there is no ‘best method’ in practice, robust methods that consider the distribution of the data can perform substantially better than the conventional methods. This article gives an overview of robust procedures, emphasizing a few that have been repeatedly shown to work well for models that are widely used in social and behavioural sciences. Real data examples show how to use the robust methods for latent variable models and for moderated mediation analysis when a regression model contains categorical covariates and product terms. Results and logical analyses indicate that robust methods yield more efficient parameter estimates, more reliable model evaluation, more reliable model/data diagnostics, and more trustworthy conclusions when conducting replication studies. R and SAS programs are provided for routine applications of the recommended robust method.     

Adult age differences in the ability to cope with situations of high arousal in a precision sport

Three field experiments are reported in which skilled miniature golf players varying in age were studied in three types of activities: training, minor competitions, and large competitions. Performance (i.e., number of shots) and arousal (heart rate and subjective ratings of anxiety) measures were registered in all types of activities. The major finding was that the level of performance of older adult players deteriorated in the large competitions, whereas groups of younger adult players, junior players, and youth players performed at the same level in all three events, although all of the groups exhibited a similar increase in arousal from training and minor competitions to large competitions. We suggest that older players may have a deficit in the ability to compensate for the negative effects of nonoptimal levels of arousal because of impairments in a variety of cognitive abilities critical to successful performance.     

Thermographic studies with fluid crystals in peripheral nerve damage

Common peripheral neurogenic lesion in various locations and of different origins were examined thermographically and the results were compared with those obtained by clinical and electromyographic methods. Lesions in the regions of the N. ulnaris and N. medianus can, except in the case of carpal tunnel syndrome, be identified without difficulty by thermography. The results obtained in the case of paresis of the radialis are non-specific, and thermographic examination of radicular lesions are also sometimes ambiguous. Damage in the plexus-brachialis and root region yield impressive results which, however, are not particularly useful.     

Readiness for professional psychotherapy

Statistics dealing with transfers to, and attendance at psychotherapy sessions and with patients' reasons for prematurely terminating such treatment are first analyzed. Causes of unwillingness to accept such treatment despite suffering are then presented. The author concludes that standards of everyday psychology require improvement, that psychotherapy should be accepted as an integral part of basic medical care, and that measures should be taken to make the symptoms indicating the need for such treatment more widely known and to give more realistic expectations of what it can achieve.     

Prostaglandins and endogenous psychoses

The authors refer to the biochemical investigation of the occurrence and metabolism of essential fatty acids in the CNS and to significant differences in results between those obtained in animal experiments and those involving human beings, taking into account hypotheses that have not yet met with general acceptance. Discussed is the possible connection between eicosanic acid and schizophrenia, notably Horrobin's hypothesis of PGE1 deficiency in schizophrenic patients. The probability of a pathogenetic connection between changes in the metabolism of fatty acids and the occurrence of endogenous psychoses is assumed.