Foltin R W
New York State Psychiatric Institute, New York 10032.
J Exp Anal Behav. 1994 Sep;62(2):293-306. doi: 10.1901/jeab.1994.62-293.
In a study examining "demand" for food, responding of 8 adult male baboons (Papio c. anubis) was maintained under a fixed-ratio schedule of food reinforcement during daily 23-hr experimental sessions. Completion of the ratio requirement resulted in the delivery of one, five, or 10 1-g food pellets. Supplemental feeding was limited to fruit and a dog biscuit daily. Responding increased as "cost" was increased across a wide range of fixed-ratio values before reaching a maximum and then decreasing. Increasing the number of food pellets per delivery decreased total responding and the number of reinforcements per day. A unit-price analysis, in which intake was converted to grams per day and fixed-ratio values were converted to responses per gram, yielded demand functions that overlapped at lower unit prices. Under one or more multiple-pellet conditions, however, intake decreased more quickly than under the one-pellet condition as the fixed-ratio value was increased in all but 1 baboon. This indicates that even when using unit-price conversions, there was variability in total intake. Although unit-price conversions yielded intake data that were more consistent across conditions, conditions differed in response topography even at the same unit prices: Under the multiple-pellet conditions there were longer pauses in responding, running response rate was slower, and the first eating bout (i.e., "meal") of the session was smaller than under the one-pellet condition. These findings (a) support the heuristic value of a unit-price analysis for studying responding for and consumption of commodities that have similar attributes, and (b) indicate that different response topographies may result in similar intakes of a commodity.
在一项研究食物“需求”的实验中，8只成年雄性东非狒狒（埃及狒狒指名亚种）的反应在每天23小时的实验时段内通过食物强化的固定比率程序来维持。完成比率要求会得到1颗、5颗或10颗1克重的食物颗粒。补充喂养仅限于每天的水果和一块狗饼干。在达到最大值然后下降之前，随着“成本”在广泛的固定比率值范围内增加，反应也会增加。每次投放增加食物颗粒的数量会减少总反应量和每天的强化次数。通过单价分析，将摄入量转换为每天的克数，将固定比率值转换为每克的反应次数，得到了在较低单价下重叠的需求函数。然而，在一种或多种多颗粒条件下，除了1只狒狒外，随着固定比率值的增加，摄入量比单颗粒条件下下降得更快。这表明即使使用单价转换，总摄入量也存在变异性。尽管单价转换产生的摄入量数据在不同条件下更一致，但即使在相同单价下，条件在反应形式上也有所不同：在多颗粒条件下，反应中的停顿时间更长，奔跑反应速率更慢，并且实验时段中的第一次进食回合（即“餐”）比单颗粒条件下更小。这些发现（a）支持了单价分析对于研究具有相似属性的商品的反应和消费的启发价值，并且（b）表明不同的反应形式可能导致对一种商品的相似摄入量。
