A portable solid-state stimulus programmer

This paper describes a miniature solid-state timing device particularly useful for presenting repetitive signal sequences in classical conditioning experiments. The device uses transistors, silicon-controlled rectifiers, and four-layer diodes, and is powered by 20-hour rechargeable nickel-cadmium batteries. Visual monitoring is provided for the unelapsed ITI and battery charge. Ranges are; ITI, 15 sec. to 5 min., ISI, 0–50 secs., CS duration, 0.5 to 30 sec., US duration, 0.5 to 30 sec. The CS and US durations are adjustable and the onset of the latter may be at any time after the CS onset. Cycling is continuous and automatic; the outputs are in the form of relay closures.     

Adaptation and repulsion in the figural after-effect

An experiment is reported which shows the effect of inspection of a curved line on the apparent curvature of a curved test line for a range of curvatures of both I and T lines. A second experiment extends the range of I curvatures, using only one T line, a straight line. The experiments showed both adaptation and repulsion components in the FAE.

An experiment by Kohler and Wallach which could not be reconciled with these results was repeated in the relevant part; the results were in agreement with the first experiment here and did not agree with those obtained by Kohler and Wallach.

An argument is presented that both adaptation and repulsion effects could be produced by a cell adaptation mechanism.     

A computer program to find the best-fitting orthogonal factors for a given hypothesis

A modification of the quartimax computation for factor rotation is described in which a hypothesized factor pattern is given to the machine along with the data. The machine uses the pattern to select the subset of variables to which it will attend when rotating in a given plane, in order to find an orthogonal solution which closely fits the hypothesis. The program also provides a measure of the goodness of this fit. The program can utilize pattern matrices that reflect only partial hypotheses as to the nature of the factors, as well as those that specify highly determined simple structure.     

Evidence

Conclusion We can now see, perhaps, what merits if any this definition has. It ties in the concept of evidence with that of law, and requires us to support our claim that some fact (or statement) is evidence for another by pointing out the science, and within it the law (or what meets the tests of being acceptable as such) whose existence alone justifies us in assuming that a certain conditional statement qualifies as acceptable as nomological. Whoever claims that a certain fact is evidence for another is required to justify his assumption that there exists a certain law. That in some sense there are such justifiable assumptions is clear from the existence of natural sciences and technologies based upon them. But it will turn out that in many cases it is impossible, as of a given moment, to make out a case for the claim that a certain conditional statement, required to support the view that a certain fact is evidence for another, is nomological. In such cases we are able to draw a clear line between what someone may think or claim is evidence, and what we have reasonable grounds for accepting as such. In short the concept offers us a principle of demarcation between justified and unjustified claims for the evidential nature of facts (or statements) offered as such. If this is not a very impressive achievement still it is not wholly contemptible, considering the confusion that prevails among many people concerning the question of evidence.