Plant breeding in vitro

Over the centuries a variety of techniques have been developed to propagate plants vegetatively — dividing, layering, and grafting. These traditional methods are all slow, however, and in recent years there has been much interest in ‘test-tube’ breeding of plants. This is not only very fast — a single rose can produce up to 400 000 descendants in a single year — but is also a very valuable means of eradicating plant diseases.     

Use of situations in mathematics education

Situations are often regarded as the panacea which guarantees concretisation of abstract notions. Recent research results have led us to qualify this opinion. After analysing briefly the notion of situation, we raise various issues on the basis of the responses of children aged 11–15 to the racing car problem. We observed various limits brought about by the situation in the abstraction prócess, and also that the task involved more abstract notions (even pictorial) than expected. The conclusion singles out some principles ensuring a better use of situations and points out key problems such as the role of mental images and the importance of the spoken language.     

A microeconometric study of theatre demand

We develop a model of theatre demand with learning by consuming, and test some of its implications on a large random sample of theatregoers and non-theatregoers. This seems to be the most comprehensive econometric study of demand for the theatre from individual data. We hypothesize that each time the consumer watches a play, he experiences a degree of pleasant or unpleasant surprise on the basis of which he will revise his future expectations of his own taste. The learning phase is likely to be unusually long for highly differentiated cultural goods. Our set of data contains unique information about the full price and the fixed cost of theatre, the objective quality of the outing, past experience of and taste for the theatre, and consumption of substitute leisure activities such as reading, television and cinema. Our methodology and data enable us to infer price elasticity on survey data from knowledge of theatregoing experience and taste. After controlling for many variables, we conclude that demand for the theatre is price-elastic, which contradicts previous estimates on aggregate time-series data. Moreover, we estimate demand conditional on past attendance after controlling for selectivity bias. Satisfaction reported by consumers after the last play is also estimated and interpreted as an ordinal conditional choice.     

Macroappraisal, the Next Frontier: An Approach for Appraising Large and Complex Government Institutions

“Macroappraisal, the next frontier” describes a records disposition pilot project which was based on a refinement of the current macroappraisal methodology in use at Library and Archives Canada. Still very much a work in progress, the refined approach builds upon macroappraisal theory and methodology, and this paper presents its application to Fisheries and Oceans Canada, a major federal government department in the Government of Canada. The project focused on providing the institution with total records disposition coverage based on a single archival appraisal and two Records Disposition Authorities. This paper demonstrates the feasibility of appraising records at the mandate level instead of at the function or program level. It also outlines and points to the benefits and advantages of appraising large government institutions intheir totality rather than in smaller, discrete sectors, branches, or divisions. We wish to thank the journal’s readers for their comments on an earlier draft of this article. We also wish to thank Candace Loewen for her insights, comments, and encouragement. Thanks are also extended to our colleagues who commented on various aspects of the project during Library and Archives Canada (LAC) appraisal seminars. Kerry Badgley also wishes to thank Sarah, Paul, and Shannon Badgley for providing a daily reminder of why it is important to document the past.