Developmental trajectories provide the empirical foundation for theories about change processes during development. However, the ability to distinguish among alternative trajectories depends on how frequently observations are sampled. This study used real behavioral data, with real patterns of variability, to examine the effects of sampling at…

In response to criticisms of a study conducted by Shaffran and Decarie, the author underscores the need for objective, accurate peer evaluation. Errors and misinterpretations in the critical article are reported and corrected. (Author/RH)

Replies to Solomon's paper that basic criticisms made earlier of Shaffran and Decaries' study still apply. Views the study as essentially a confirmation of the null hypothesis based on weak measures. (Author/RH)

Maintains author's interpretation of 6-month-olds' behavior is consistent with task requirements in the 2000 study and previous work showing that infants use explanatory inferences to make sense of their world. Asserts that ability to understand that people communicate with persons but act on objects is precursor to infants' understanding at 9 to…

This paper is a discussion of the different contexts in which the concept of the infant's state is used in infant research. The infant states discussed are: regular sleep, irregular sleep, drowsiness, alert inactivity, waking activity, and crying. Also included are hunger periods and indeterminate states, those instances in which an infant's state…

Analyzes methods used to record infant head position and the limits of these methods. An experimental device is proposed which records infant head turning and head righting when the vestibular system is stimulated. (Author/DB)

Examines nine studies claiming to have demonstrated facial imitation in the neonatal period. Finds that the claims of early imitative abilities are not well founded: because the matching behavior found is restricted to a single gesture--tongue protrusion--it is best explained as a specific, directly elicited response, rather than imitation. (HTH)

Focuses on the experimental designs and methodology of 15 studies, most of which used only part of the methodology for the experimental analysis of behavior. Argues that the failure to fully use available research technology may have contributed to researchers' failure to make experimental contact with the definition of reinforcement. (RH)

Maintains that findings showing numerical computation abilities in infants are considerably more robust and consistent than Wakeley, Rivera, and Langer suggest. Asserts that all the interim replication attempts have successfully replicated Wynn's original findings. Discusses possible reasons for failure to replicate in Wakeley et al. experiments.…

This study investigated the common practice in infant research of eliminating from reported data large numbers of subjects who prove uncooperative (sleepy, fatigued, fussy) during the experiment. It was suggested that these excluded infants constitute a special class of subjects and that the inclusion of their data would greatly alter the research…

Aims to clarify the distinction between elicitation and reinforcement discussed in Bloom (1984); to make explicit theoretical and methodological assumptions about the experimental analysis of infant behavior as shown in components of Poulson (1983); and to clarify differences in interpretation of other infant vocal conditioning research.…

Multiple discriminant function analysis was conducted with data from Strange Situations. Results enable researchers to obtain attachment classifications directly from scores on interactive behavior and crying during reunion episodes. (PCB)

Discusses two problems in the study by Blass and Ciaramitaro reported in this monograph: (1) whether the measurement of behavior states as "on-off" or "graded" captures a behavioral process or reflects the measurement itself; (2) whether the term "state" explains findings as a single function that may be better…

Asserts that findings on whether young infants look longer at incorrect addition and subtraction have been inconsistent or negative. Hypothesizes that imprecise ordinal calculating with very small numbers of objects develops in late infancy and that precise calculating develops in early childhood. (Author/KB)