Optimization models have often been useful in attempting to understand the adaptive significance of behavioral traits. Originally such models were applied to isolated aspects of behavior, such as foraging, mating, or parental behavior. In reality, organisms live in complex, ever-changing environments, and are simultaneously concerned with many behavioral choices and their consequences. This target article describes a dynamic modeling technique that can be used to analyze behavior in a unified way. The technique has been widely used in behavioral studies of (...) insects, fish, birds, mammals, and other organisms. The models use biologically meaningful parameters and variables, and lead to testable predictions. Limitations arise because nature's complexity always exceeds our modeling capacity. (shrink)

A B S T R A C T Detailed examination of audio recordings of business-to-business `field-sales' encounters are used to report one way in which salespeople elicit verbal expressions of affiliation from their prospective customers — by reciprocating second assessments which affiliate with, trade off and build on prospects' own assessments. This article outlines the prototypical features of these junctures of assessment-affiliation and describes how salespeople can mobilize such assessments to build extended sequences of `rapport' that take the form of (...) adjacent and mutual expressions of substantive verbal affiliation. Consideration is also given to explicating both the interactional basis of these sequences as well as the socially obligating influence such affiliation and rapport can have on sales outcomes. (shrink)

Professor Toynbee's definition of the proletariat is an unusual one. To him, ‘proletarianism is a state of feeling rather than a matter of outward circumstance.’ Still more allusively, a proletariat is ‘any social clement or group which in some way is “in” but not “of” any given society at any given stage of such society's history’. Marx defined the word to mean the urban wage workers in modern society. To Professor Toynbee, Marx's definition is what a mathematician would call ‘a (...) special case’; and although it is perhaps the largest, it is by no means the sole constituent of the proletariat by Professor Toynbee's definition. It is also possible on Professor Toynbee's definition—this is an essential aspect of the matter which he has not followed up and which is one of the principal subjects of the following article—that a man may be an urban wage worker without being a proletarian. (shrink)