SKED-controlled experimentation in an undergraduate instructional laboratory

A SKED-based facility for undergraduate instructional research has been operating for over a year. The two-computer approach, with one machine for programming and the other for running experiments, is used. Criteria for computerized undergraduate research laboratories, benefits of SKED, and the two-computer approach are discussed.     

The Cost-Reward Model of Helping Behavior: A Nonconfirmation1

A field experiment was designed to test several predictions derived from the Piliavin and Piliavin cost-reward model of helping behavior. Female and male subjects' reported intent to help a hemophiliac in a nearby hospital was unrelated to the costs for helping, the costs for not helping, and the order in which the subjects received the costs' manipulations. The obtained rates of helping were also unrelated to whether or not subjects reported having donated previously. Failure to obtain the predicted results is discussed.     

A comparison of the key-peck and treadle-press operants in the pigeon: differential-reinforcement-of-low-rate schedule of reinforcement

Key pecking and treadle pressing in pigeons were compared under concurrent (key-treadle) and single-operant differential-reinforcement-of-low-rate schedules of food reinforcement ranging from 5 to 60 sec (concurrent procedure) or 5 to 120 sec (single-operant procedure). Under both procedures, the two operants followed the same general law: decreasing response rate and reinforcement rate and increasing number of responses per reinforcement as a function of increasing schedule interval. High correlations were found between key pecking and treadle pressing for the measures of response rate, reinforcement rate, and responses per reinforcement. Regression equations allowed the prediction of treadle pressing from key pecking. More bursting occurred in responding to the key, and key pecking showed a more precise temporal discrimination than treadle pressing. A test for sequential dependencies between key and treadle responses showed significant dependencies not only under the concurrent procedure but also in data created artificially by merging key and treadle sequences from different pigeons under the concurrent procedure and from the same pigeon under the single-operant procedure. It seems likely that the sequential dependencies found were due to the independent action of the schedule on each operant and that behavioral dependencies did not occur with the concurrent training procedure. The key-peck operant does not appear to have any special qualities that preclude its use in discovering general laws of behavior, at least under the differential-reinforcement-of-low-rate schedule. The usefulness of the key peck in other situations requires direct experimental study.     

Manipulation of response-contingent unconditioned-stimulus intensity in human eyelid conditioning: A two-phase model analysis

Four groups of human subjects were given 360 classical eyeblink conditioning trials. All groups received the same UCS (unconditioned stimulus) intensity on[Formula: see text] (nonconditioned response) trials but differed in the intensity presented on CR trials. Response probability increased as a positive function of UCS intensity on CR trials. Phase 1 of the two-phase model was longer when no UCS was presented on CR trials, but did not differ in duration among the remaining three groups. Most subjects could be described with a single operator in Phase 2, the operator limit increasing as a positive function of CR-contingent UCS intensity. For subjects requiring different operator limits on CR and[Formula: see text] trials, the latter was lower with high CR-trial intensities but higher with low CR-trialintensities. The results were interpreted to be more consistent with drive theory than with "law-of-effect" or two-factor theories.     

How to keep romance in your marriage

Pastoral Psychology -     

Adults' difficulties in identifying concealment among children interviewed with the putative confession instructions

The putative confession (PC) instructions (“[suspect] told me everything that happened and wants you to tell the truth”) increases children's honesty. However, research has shown that children who maintain secrecy despite the PC are more convincing. We examined whether (a) the PC undermines adults' deception detection abilities or (b) children who conceal despite the PC are better deceivers. Adults evaluated truthful and deceptive children interviewed with the PC where the PC portion of the interview was either present or absent. Adults' deception detection was no worse when the PC was present; in fact, it was slightly better. Rather than negatively affecting adults' ability to detect deception, the PC selects an unusually convincing group of concealers.