Variations on the Theme of Remembering: A National Survey of How Canadians Use the Past

This paper in collective remembering is based on a telephone survey of 3,419 adult residents of Canada. The questionnaire contains over 70 questions. The interviews average over 20 minutes in length. Part of the Canadians and Their Pasts project, the survey seeks to assess how Canadians use the past in daily life. How many engage in activities related to the past, such as reading books, viewing photos, or visiting museums and historic sites? How do they evaluate different sources of information about the past? What types of past — family, province, nation, ethnic group — are most important to them? The paper suggests that the construction and reconstruction of autobiographical memory is a fundamental aspect of one’s uses of the past. It also proposes that wider collective pasts are particularly important among members of minority and alternative groups. And that the past of the nation-state figures more prominently in these citizens’ reflections than Roy Rosenzweig and David Thelen observed in their similar study, The Presence of the Past: Popular Uses of History in American Life (1998).Cette étude de remémoration collective s’appuie sur une enquête téléphonique menée auprès de 3,419 adultes résidant au Canada. Comportant plus de 70 questions et nécessitant des entretiens de plus de 20 minutes, l’enquête, effectuée dans le cadre du projet Les Canadiens et leurs passés, vise à évaluer l’utilisation du passé dans la vie de tous les jours. Combien de Canadiens et de Canadiennes se livrent à des activités liées au passé, telles que lire un livre, regarder des photos ou visiter un musée ou un lieu historique? Comment évaluent-ils les différentes sources d’information sur le passé? Quels types de passé priment pour eux : celui de leur famille, de leur province, de leur pays, de leur groupe ethnique? Le présent article avance l’idée que la construction et la reconstruction du souvenir autobiographique sont des aspects fondamentaux de l’utilisation du passé. Il affirme que les passés collectifs sont tout particulièrement importants chez les membres des minorités et des groupes divergents. Et il laisse entendre que le passé de l’État-nation est beaucoup plus présent dans les réflexions de ces citoyens que ne l’ont constaté Roy Rosenzweig et David Thelen dans leur étude semblable, The Presence of the Past: Popular Uses of History in American Life (1998)

Bit-Vector Model Counting using Statistical Estimation

Approximate model counting for bit-vector SMT formulas (generalizing \#SAT) has many applications such as probabilistic inference and quantitative information-flow security, but it is computationally difficult. Adding random parity constraints (XOR streamlining) and then checking satisfiability is an effective approximation technique, but it requires a prior hypothesis about the model count to produce useful results. We propose an approach inspired by statistical estimation to continually refine a probabilistic estimate of the model count for a formula, so that each XOR-streamlined query yields as much information as possible. We implement this approach, with an approximate probability model, as a wrapper around an off-the-shelf SMT solver or SAT solver. Experimental results show that the implementation is faster than the most similar previous approaches which used simpler refinement strategies. The technique also lets us model count formulas over floating-point constraints, which we demonstrate with an application to a vulnerability in differential privacy mechanisms