The simulations we presented above illustrate an interesting emergent prediction of SOCR (). When we compare the response strengths of the Acq groups which share the same ratio of the total CS duration between USs to the US-US interval, they are roughly the same. Specifically, the response strength of the Acq-Short group in the top panel and that in the Acq-Spaced group in the middle panel are roughly the same, about 0.8, despite the absolute duration of the CS and the US-US interval being ten times longer in the Acq-Spaced group than in the Acq-Short group. Similarly, the response strengths in the Acq-Long and Acq-Partial groups in the top panel and those in the Acq-Long and Acq-Partial groups are all similar, around 0.4, despite the fact that the distributions and absolute durations of the CS between USs and the US-US interval are different. Thus, at least with the current set of parameters, an effect like timescale invariance was simulated. This is superficially surprising in that the strength of Link 1 is different, especially between Long and Partial groups in the top and middle panels. The timescale invariance-like predictions arise because when the CS duration and the US-US interval are both expanded, the weakening of Link 1 is accompanied by a compensating weakening of comparator effect of the context. However, if we expand the absolute duration of the CS and the US-US interval to the extreme, the SOCR predicts that the effectiveness of Link 1 will decline and consequently the CS will finally lose its response potential, even though the ratio between the total CS duration between USs and the US-US interval was fixed. Thus, SOCR can explain and predict timescale invariance to some extent, but it clearly predicts that the effect will no longer be observed if the timescale is made extremely large.
The mechanism by which selenium protects against the toxicity of methylmercury is not known, but the fact that vitamin E and certain antioxidants also decrease methylmercury toxicity (Welsh & Soares, 1976; Welsh, 1979) has prompted the hypothesis that these compounds may diminish methylmercury toxicity by counteracting the damaging effects of the free radicals generated by its breakdown (Ganther, 1978).
Multiple comparisons problem - Wikipedia
From the comparative survey of available energy planning models, it was found that the environmental considerations are limited only to estimating the pollution load, thus sending false price signals to the technology market and leading to environmentally distorted policy decisions.
support the research or alternative hypothesis
In thepresent paper, we demonstrate that using the ML-SEM rather than the SL-SEM framework to estimate the parameters of thesemodels can be practical when the study involves (1) a large number of time points, (2) individually-varying times ofobservation, (3) unequally spaced time intervals, and/or (4) incomplete data.
The case for the comparator model as an explanation …
The model proposed by allows simulation of a series of phenomena on a trial-by-trial basis. On the one hand, this has the merit of simplicity. On the other hand, it is not ideal for situations in which the temporal durations of trials and ITIs differ across conditions. Thus, in order to simulate the present two experiments which include three different CS durations and two different US-US intervals, we modified their model slightly so that we could deal with multiple durations of CSs and ITIs in a consistent manner. In the simulation presented here, all conditioning treatments were divided into 2.5-sec long segments (the shortest CS duration in present experiments), and all increments and decrements of associative strength were calculated based on the presence and absence of each stimulus in that segment. In conjunction with this modification, changes in two parameters were necessary in order to obtain realistic values for each associations: The salience of context was set at 0.17 rather than the 0.35 assumed by Stout and Miller, and k1 (the extinction rate parameter) was set at 0.014 rather than 0.14. These changes were made because if we used the original parameters in the present real-time simulation, all stimuli, especially the context, lost associative strength too rapidly due to decrements in each successive 2.5-sec time bin. All other parameters were the same as those used in Stout and Miller: k2 (proportional impact of comparator process) was set at 0.9, salience of overshadowing cue at 0.71, and salience of target cue at 0.35.
CS-duration and partial-reinforcement effects …
Rating scales are often criticized for using relatively vague references to frequency of behavior, such as "sometimes," "often," or "very often." To some extent, such criticisms are quite justified if one is interested in very precise fine grain frequency counts of behavior as might be gleaned from direct behavioral observations or test responses, such as on a reaction time task. Such precise frequency counts may be necessary, in fact, to test certain psychological hypotheses. But at the level of clinical practice and judgment and for other research purposes where such precision is often unnecessary and unduly costly and cumbersome, the more general judgments of individuals based upon their own observations of themselves or others have proven to be sufficiently accurate, convenient, inexpensive, and most importantly, reliable, valid, and predictive to be of great utility. Indeed, research comparing the scores derived from clinical tests, such as continuous performance tests or even driving simulators, has often found the test scores to be less predictive of their respective constructs as assessed in natural settings (parent and teacher ratings or inhibition and attention or department of motor vehicle records or reports of others about one's driving, respectively) than are ratings of the individual's test-taking behavior in that same setting completed by the examiner (Barkley, 1991; Barkley, Murphy, DuPaul, & Bush, 2002; Shelton, Barkley, Crosswait, Moorehouse, Fletcher et al., 1998). To reiterate, each approach to measurement has its place depending on the purpose of the evaluation.