By solving a model photodetachment problem, we show how the standard Floquet wave function for a system driven by a harmonic potential is modified by the presence of coupling to the continum.

(1982). CHILDREN'S UNDERSTAHDING ABOUT VERBAL COMMUNICATION. Early Years: Vol. 2, No. 2, pp. 48-53.

36 children aged between 4-4 and 5-4 were assessed for both their understanding about the role of message ambiguity as a cause of communication failure, and their level of performance in verbal referential communication tasks. All children then took part in six half-hour sessions during which they practised listening and speaking in small groups, with the experimenter modelling appropriate behaviour on her turns. In addition, half the children received information about when and why listeners understood or failed to understand (metacognitive guidance) during the course of the sessions. Both groups improved in both performance and understanding in the immediate post-test and in a delayed post-test seven weeks later there was no sign of regression in understanding. The guidance group advanced more than the practice group in both performance and understanding (with the exception of those at the highest levels of understanding originally). Performance and understanding measures were significantly related to each other in the pre-test, and the relationship remained unchanged following intervention, with the exception of question-asking, which increased even among children who made no advances in understanding. The results were interpreted as suggesting that we can advance children's verbal communication skills not only by giving them information about communication, but also by treating them as though they understand that messages can be ambiguous and can cause communication failure.

AbstractTested the hypothesis that explicit identification of message ambiguity as a reason for failure in referential communication could help young children to gain understanding about the need for unique reference in communicative acts, in both experimental and natural settings. In the experiment each of 47 children aged 5‐2 to 6‐5 selected and then described clothes for a doll so that the experimenter could choose matching items. Ambiguous instructions from the children were consistently responded to with one of three reactions by the experimenter: (1) she guessed an item, (2) she asked ‘Which one?’ waited and chose or (3) she made explicit why she could not make a unique choice on the basis of the child's message. Both before and after this manipulation children were assessed for their understanding that messages can be ambiguous and can cause communication failure. Children accorded the third treatment improved most both in understanding and in reducing the ambiguity of their messages.A similar assessment of understanding was made of 36 6‐year‐old children of whom recordings of interaction in the home had been made over several previous years. Children whose mothers had made explicit their lack of understanding of their child's utterances were more advanced than those whose mothers had not.