Children's expression of jealousy was studied in a cross-sectional sample of children. In the first study, 56 females and 56 males, ages 4.5 months to 4.5 years, were videotaped while their mother paid exclusive attention to another child in a social situation thought to evoke jealousy. In the second study, 10 girls and 10 boys, ages 4.9-7.3 years, were videotaped while their mother praised another child's drawing. We present indications that the emotional state of jealousy can be reliably and validly inferred from the children's behavior in these social settings. Jealousy emerged most intensely in the majority of children between approximately 1.1 and 2.3 years and at 3.5 years children distinguished between social situations which elicit jealousy. These findings are related to the cognitive developmental theories of Case et al. (1988) and Fischer et al. (1989).

The results will be relevant to nutritionists in the development of effective resources and training for childcare centre menu planners.

Do 9-15-week-old infants produce differentially organized hand and arm actions in relation to affective states when presented with social and nonsocial stimuli? This question was examined by observing 8 infants longitudinally. They were observed when facing their active and passive mother and an active and passive doll during 4 visits at biweekly intervals. Videotapes were coded in real time using the following measures: Vocalization, Gaze, and Gaze Avert; for face, Smiling, Distressed, and Neutral; for hands, Pointing, Open, Curled, and Closed; and for arms, Extended and At Side. Co-occurrence and lag sequential analyses showed that hand actions were organized with other infant actions to form unique behavioral linkages in each of the 4 conditions. The implications of these findings for the development of nonverbal communication are discussed.

In Empirical results are presented that point toward consistent violations of intradimensional ("segmental") additivity in dissimilarity judgments about rectangles. These results contradict all Minkowski power metrics, and support a recently introduced "metric for bounded response scales" (MBR) that predicts intra-and interdimensional subadditivity. We found strong indications of systematic individual differences. We therefore analyzed the individual dissimilarity judgments for four groups separately, first at the within-subjects level and later at the group-average level. The stability with which our results replicated across the independent groups served as a consistency and robustness check. Since numerous metrics other than the MBR might account for segmental subadditivity, we compared the fit of four versions of the MBR, the three major Minkowski metrics, and two alternative segmentally subadditive metrics. The city-block metric uniformly gave the worst fit. We obtained the best fit for an MBR that reduces the upper bound by about one-fifth of the response scale range. No significant improvement was obtained by permitting the upper bound to vary from subject to subject. Although the orientation question (whether subjects employed a height/width or an area/shape system) could not be resolved conclusively, it appeared that the largest group used height and width, whereas the second-largest group used shape predominantly.

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