Timeout from concurrent schedules.

Assessing Animals’ Preferences: Concurrent Schedules of Reinforcement

Matching and Maximizing in Concurrent Schedules

In a recent article, Staddon and Motheral derived a mathematical model of responding in concurrent variable-interval-variable-interval schedules. According to this model, maximization of overall reinforcement rate predicts the operant matching law. However, Staddon and Motheral's derivation ignores a fundamental aspect of the concurrent schedule contingency. There are two simultaneously availab...

Timeout!

We were working through our usual busy agenda during our P&T committee meeting at Thomas Jefferson University when an item caught me by surprise. A member of our urology department was attempting to explain why we ought to approve a new prostate cancer drug that costs a jaw-dropping $93,000 per course of therapy. His words caused me to straighten up in my chair and to lean in closely so that I ...

Time Loss Loss Threshold Threshold Timeout Timeout

In this paper we analyse congestion in TCP over ATM-UBR, in particular the association between the congestion measures at the ATM physical and TCP transport layers. In addition to the commonly used metrics, cell loss ratio (CLR) and packet retransmission ratio (PRR) two new indicators, protocol level congestion association factor (PLCAF) and CLR-PRR correlation coe cient are used. CLR and PRR a...

Concurrent drinking by pigeons on fixed-interval reinforcement schedules.

Three experienced pigeons were exposed to at least ten consecutive 100-min sessions on each of three food-reinforced fixed-interval (FI) schedules: FI 50-sec, FI 100-sec and FI 200-sec. Water was freely available. Drinking was largely confined to the first third of each fixed interval, and the mean sessional water intake was directly related to the food-reinforcement rate for each animal. The a...