Ricerc@Sapienza

When one interprets Candecomp/Parafac (CP) solutions for analyzing three-way data, small loadings are often ignored, that is, considered to be zero. Rather than just considering them zero, it seems better to actually model such values as zero. This can be done by successive modeling approaches as well as by a simultaneous modeling approach. This paper offers algorithms for three such approaches, and compares them on the basis of empirical data and a simulation study.

We present a psychological model of extremism based on the concept of motivational imbalance whereby a given need gains dominance and overrides other basic concerns. In contrast, moderation results from a motivational balance wherein individuals' different needs are equitably attended to. Importantly, under moderation the different needs constrain individuals' behaviors in prohibiting actions that serve some needs yet undermine others. Those constraints are relaxed under motivational imbalance where the dominant need crowds out alternative needs.

Data obtained by studying mammalian cells in absence of gravity strongly support the notion that cell
fate specification cannot be understood according to the current molecular model. A paradigmatic case in
point is provided by studying cell populations growing in absence of gravity. When the physical
constraint (gravity) is ‘experimentally removed’, cells spontaneously allocate into two morphologically
different phenotypes. Such phenomenon is likely enacted by the intrinsic stochasticity, which, in turn, is