Effects Of Procedural Variables Research Articles

Some effects of procedural variables on operant choice behavior

Procedural variables are concerned with the way subjects contact stimulus, response, and reinforcer variables and relations in an experiment. Procedural variables may therefore be understood as tools that allow researchers and theorists to explore the generality of their conceptions of independent variables, behavioral processes, and quantitative laws of behavior. The present article reviews data from several studies showing how procedural variables can influence the outcome of operant choice experiments, even when nominal independent variables remain constant. An important theoretical issue raised by these data is whether researchers have most usefully identified the independent variables that they incorporate into their quantitative models. Particular attention is paid to how procedural variables can influence the measure of reinforcement frequency over time that best correlates with the distribution of choice responding over time.

Deciding mental retardation and mental illness in capital cases: The effects of procedure, evidence, and attitudes

When finding unconstitutional the execution of defendants who were mentally retarded at the time of their crime in Atkins v. Virginia (2002), the US Supreme Court left the States to decide on procedures for deciding a defendant's mental retardation. This has and will lead to substantial variation, and will include juries being responsible for these verdicts. Two studies are presented that test procedural, evidentiary, and attitudinal effects on mock juror verdicts as to a capital defendant's mental retardation. Both studies show significant effects of procedural variables. Making the retardation and death decision at the same trial phase changed jurors’ interpretation of evidence, including severity of mental problems. Jurors were insensitive to differences in the burden of proof on mental retardation verdicts, although demanding proof beyond a reasonable doubt may make jurors more sensitive to retardation evidence when deciding on a death sentence. Areas for future research are outlined.

Thermal Decomposition of Dolomite in an Atmosphere of Carbon Dioxide: The effect of procedural variables in thermal analysis

The effects of procedural variables on dolomite decomposition in carbon dioxide were investigated. The partial pressure of carbon dioxide causes dolomite decomposition to split into a two-stage process. It was observed that the first stage of dolomite decomposition is progressively displaced to higher temperatures with an increase in heating rate. However, the second stage is not affected significantly by changes in the heating rate. These studies also indicate that decrepitation analysis on dolomite in CO2 provides better information as compared to experiments in other atmospheres. The flow rate of the purge gas does not influence the thermal behavior of dolomite.

Effects of procedural variables on the deaquation—anation of aquapentaamminecobalt(III) salts

A kinetic investigation of the solid-phase deaquation—anation reactions of [Co(NH 3) 5H 2O]X 3, where X − = Cl −, Br − or NO − 3 is reported. Because of the poor agreement in activation parameters reported in the literature for this series of reactions, this investigation includes a study of the effects of several experimental factors on these parameters. The factors studied include particle size, sample size, atmosphere, heating rate and compaction of the sample. Both isothermal and non-isothermal experiments are utilized and an investigation of the isokinetic relationship for these reactions is included. There is a linear correlation of Δ H ≠ with Δ S ≠ in the isothermal studies giving an isokinetic temperature of 362 ± 7 K. The results of this study suggest that previous assignment of an S N2 type mechanism for this series based on variations in activation parameters is unwarranted.

Auditory filter characteristics inferred from simultaneous masking: effects of procedural variables

In a previous experiment [R. H. Margolis and A. M. Small, J. Speech Hearing Res. 18, 571–587 (1975)] the characteristics of the auditory filter were investigated by measuring the detectability (d′) of a long duration (250 msec) tonal signal as a function of the cutoff frequency of a continuous, low-pass, computer-synthesized, noise masker. In the present research, two experiments were conducted to explore the effects of certain procedural variables on the characteristics of the auditory filter inferred from low-pass masking data. In experiment I auditory filter characteristics were found to be critically dependent upon the range over which d′ is allowed to vary. Baseline detectability and the procedure for computing d′ from P(C) were found to be critical variables. In experiment II the effect of a pulsed versus continuous masker was explored. The signal was a 500-msec tone with a rise-fall time of 25 msec. The masker was gated identically to the tone or left on continuously. Tonal signals were slightly more detectable in the pulsed masker condition. The results of these experiments have led to the design of a notch-noise, pulsed-masking experiment for the investigation of auditory filter characteristics in normal and pathological ears. [Work supported by NIH and the Deafness Research Foundation.]

The effect of scopolamine on the stimulus change phenomenon

Saline treated rats chose a novel stimulus, whereas rats injected with scopolamine showed no preference for a novel or familiar stimulus. Scopolamine decreased the latency to approach the stimulus. The effects of procedural variables on drug-induced changes is stressed.

Effects of procedural variables upon reversal and interdimensional shift performance: I

College Ss accomplished a reversal (R) shift faster than an interdimensional (IRD) shift over three different methods of problem presentation, when no cue cards were present. With cue cards present there was no difference between Rand IRD shifts. The latter finding reflects an increase in the difficulty of the R shift resulting from the necessity for S to sort contrary to cue cards whenever a R shift is made.

Effects of procedural variables upon reversal and interdimensional shift performance: II

College Ss were found to accomplish a reversal (R) shift faster than an interdimensional (IRD) only when simple preliminary instructions were used. The results suggest that with sufficient information Ss adopt a hypothesis-testing strategy, (in concept identification problem) similar to that described by Restle’s model (1962).