Plans do not serve the particular circumstances of a given situation, but rather serve as abstract descriptions of some future activities. The relationship between plans, which are abstract, and actions, which are concrete, is referred to as the relationship between plans and situated actions. This relationship can be formulated in the following questions: 1) How do individuals conceive of future activities? 2) How does an individual who is acting upon a plan adjust when facing contingencies? The relationship between plans and situated actions has remained a source of intense academic discussions (e.g., Bardram, 1997; Bardram & Hensen, 2010; Leudar & Costall, 1996; Ng, 2002; Schmidt, 1997; Suchman, 1987). Despite the ample research on the relationship between plans and situated actions, a review of the literature indicates that the problem has not been adequately addressed (Randall et al., 2007; Suchman 2003), which has compelled this researcher to create a theoretical model that integrates the disparate nature of plans and line of actions. Drawing on research on cognition and categorization theory, this thesis proposes a theoretical framework that conceptualizes the relationship between plans and situated actions in terms of activity categories. Specifically, the theoretical framework draws on the prototype and basic-level category theories of categorization, both of which were developed primarily by Rosch (1978), as well as the field theory developed by Lewin (1936). Categorization theories are used to address plans’ abstractness as they capture typifications of human experience. Field theory is used to address the concreteness of action as it captures dynamic properties of the situation in the here and now. The basic premise of the theoretical framework is that individuals conceive (have a knowledge) of plans and their attributes as future activity categories with a range of possibilities. These possibilities are structurally graded, ranging from highly typical to atypical. Plans are believed to be formed based on what is typical for the activity. The theoretical framework argues that an association exists between an individual’s knowledge of typical adjustment relevant to the activity and actual adjustment the individual makes while performing the activity. With this in mind, the theoretical framework considers the actor’s perspective to be central to the investigation. Based on the theoretical framework, several hypotheses are formularized and tested. An in-depth case study conducted in a ready-mix concrete company was used to examine aspects of the theoretical framework empirically. The results of the case study provide a wide range of independent evidence supporting the framework. In addition, an experimental methodology was developed for quantitative testing in the laboratory aspects of the theoretical framework not attainable in the case study. Theoretical and practical implications of the proposed framework and empirical findings are examined. Future research directions are discussed.

Plans do not serve the particular circumstances of a given situation, but rather serve as abstract descriptions of some future activities. The relationship between plans, which are abstract, and actions, which are concrete, is referred to as the relationship between plans and situated actions. This relationship can be formulated in the following questions: 1) How do individuals conceive of future activities? 2) How does an individual who is acting upon a plan adjust when facing contingencies? The relationship between plans and situated actions has remained a source of intense academic discussions (e.g., Bardram, 1997; Bardram & Hensen, 2010; Leudar & Costall, 1996; Ng, 2002; Schmidt, 1997; Suchman, 1987). Despite the ample research on the relationship between plans and situated actions, a review of the literature indicates that the problem has not been adequately addressed (Randall et al., 2007; Suchman 2003), which has compelled this researcher to create a theoretical model that integrates the disparate nature of plans and line of actions. Drawing on research on cognition and categorization theory, this thesis proposes a theoretical framework that conceptualizes the relationship between plans and situated actions in terms of activity categories. Specifically, the theoretical framework draws on the prototype and basic-level category theories of categorization, both of which were developed primarily by Rosch (1978), as well as the field theory developed by Lewin (1936). Categorization theories are used to address plans’ abstractness as they capture typifications of human experience. Field theory is used to address the concreteness of action as it captures dynamic properties of the situation in the here and now. The basic premise of the theoretical framework is that individuals conceive (have a knowledge) of plans and their attributes as future activity categories with a range of possibilities. These possibilities are structurally graded, ranging from highly typical to atypical. Plans are believed to be formed based on what is typical for the activity. The theoretical framework argues that an association exists between an individual’s knowledge of typical adjustment relevant to the activity and actual adjustment the individual makes while performing the activity. With this in mind, the theoretical framework considers the actor’s perspective to be central to the investigation. Based on the theoretical framework, several hypotheses are formularized and tested. An in-depth case study conducted in a ready-mix concrete company was used to examine aspects of the theoretical framework empirically. The results of the case study provide a wide range of independent evidence supporting the framework. In addition, an experimental methodology was developed for quantitative testing in the laboratory aspects of the theoretical framework not attainable in the case study. Theoretical and practical implications of the proposed framework and empirical findings are examined. Future research directions are discussed.

Ce travail porte sur la catégorie d’action publique « jeunes en errance ». Il vise à comprendre son impact sur la mise en œuvre de l’action publique sur le terrain au travers de l’analyse des usages qu’en font les acteurs professionnels et les jeunes eux-mêmes. Après avoir retracé les étapes de la constitution du phénomène de l’errance des jeunes en problème public, nous avons analysé le rôle de l’Etat social dans la prise en charge de ce problème, au prisme de la norme instituée de l’insertion pour les jeunes. Ceci nous a permis d’en pointer les apories et notamment la bascule rapide des jeunes cumulant des difficultés depuis l’enfance vers le circuit de l’infra-assistance. A l’aune de ces constats, nous montrons en quoi la relation d’aide devient un lieu de renégociation des objectifs de l’action publique, les artisans de la relation d’aide considérés étant les professionnels de terrain et les jeunes usagers des services d’aide. L’analyse des pratiques professionnelles nous a révélé leur caractère « bricolé ». Nous avons ici pu démontrer qu’elles permettaient de redéfinir les cadres de l’action publique en direction des « jeunes en errance ». Grâce à la mise en place d’une éthique de l’intervention centrée sur la prise en compte des spécificités des jeunes accueillis, les professionnels fabriquent des ponts leur permettant d’aller au-delà des manques de l’aide publique. Nous avons également analysé les comportements des jeunes fréquentant régulièrement les structures de l’urgence sociale. Leur mode de recours à l’aide leur permet d’asseoir une identité légitime de « jeunes en errance », qu’ils valorisent au sein de la relation d’aide. Ils mettent en place des stratégies identitaires les autorisant à renégocier les cadres de l’attribution de l’aide, en y ayant recours de manière détournée ou partielle. Ils ignorent ainsi les objectifs d’insertion qui lui sont attachés, en en faisant un usage routinier, les entretenant alors dans une carrière de « jeunes en errance ». / This research investigates the French public action category “jeunes en errance” (which will be translated by “homeless youth”). It aims at understanding the impact of this category on the implementation of the public action, through the analysis of the usage that both the professional actors and the youth make of it. After having redrawn the stages of the construction of the homeless youth phenomenon as a public problem, the analysis focused on the role of the Welfare state based on the instituted norm of the youth’s integration. Paradoxes of public action have thus been identified, such as the quick turnaround towards the infra-assistance system of young people who have accumulated difficulties since their childhood. In the light of these findings, the research then shows how this “support relationship” transforms itself in an arena for the renegotiation of the public action's objectives between the professionals on the one hand, and the youth recipients of the services on the other hand. The analysis of the professional's practices puts the light on their unstable dimension. The research has shown that these practices facilitated the redefinition of the frameworks of the public action toward “homeless youth”. Through the setting of an intervention’s ethics based on the specificities of each young person, the professionals manage to compensate the shortages of public assistance. The behavior of young people who frequently resort to the structures of social emergency have also been investigated. The analysis has identified the process of construction of a legitimate identity of “homeless youth”, which young people put forward within the assistance relationship. They set up identity strategies which enable them to renegotiate the conditions of the allocation of support, by resorting to it but only in a partial or in an indirect way. Thus, they ignore the insertion objectives which are attached to these public measures and make a routinized usage of them, which contributes to maintain them in a “homeless youth” career.