The generalized matching law can be applied to a signal-detection matrix to give two equations. The first relates responding in the presence of the stimulus to the reinforcements for the responses, and the second relates responding in the absence of the stimulus to the reinforcements for the responses. Evidence for stimulus discrimination is given by biases that are opposite in sign in the two equations. As the logarithmic ratio and z proportion transformations are similar, the combination of the absolute values of the two logarithmic biases gives a measure equivalent to the signal-detection measures d' and eta. The two equations can also be combined to eliminate the biases caused by the signalling stimuli and to produce a generalized matching-law statement relating overall performance to the obtained reinforcements.

The field of behavioral economics combines concepts from economics and operant conditioning to examine the influence of schedules or price on preference for reinforcers. Three case studies are reported in which behavioral economic analyses were used to assess relative preference for reinforcers shown by people with intellectual disabilities when schedule requirements varied. The studies examined (a) preference for different reinforcers, (b) substitutability of reinforcers, and (c) changes in preference as a function of schedule requirements.

Using an A-B-A-B design, two procedures for requesting a change of activity were compared for their effect on the stereotypic behavior of a man with autism. One procedure requested immediate change of activities, whereas the second procedure gave advance notice of a change. Less stereotypy occurred when advance notice of change was given.

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The undecapeptide substance P (SP) is a member of the tachykinin family of neurotransmitters, which has a pivotal role in the regulation of inflammatory and immune responses. One of the major barriers to the study of the in vivo role of SP in a number of immune disorders is the accurate measurement of SP in fluids. This is reflected in the variability of reported SP levels in serum and plasma of humans in both healthy and diseased states. This study was initiated in order to identify sources of variability by the comparative evaluation of the influences of sample preparation and analytical detection methods on the measurement of SP in plasma. The results indicate that sample preparation (peptide extraction versus no extraction) and the choice of analytical method for SP quantitation may yield significantly different values and may contribute to the variability in SP values reported in the literature. These results further emphasize the need for careful consideration in the selection of methods for SP quantitation, as well as caution in the interpretation and comparison of data reported in the literature.