Interrupted time-series graphs are often judged by eye. Such a graph might show, for example, patient symptom severity (y) on each of several days (x) before and after a treatment was implemented (interruption). Such graphs might be prone to systematic misjudgment because of serial dependence, where random error at each timepoint persists into later timepoints. An earlier study (Matyas & Greenwood, 1990) showed evidence of systematic misjudgment, but that study has often been discounted due to methodological concerns. We address these concerns and others in two experiments. In both experiments, serial dependence increased mistaken judgments that the interrupting event led to a change in the outcome, though the pattern of results was less extreme than in previous work. Receiver operating characteristics suggested that serial dependence both decreased discriminability and increased the bias to decide that the interrupting event led to a change. This serial dependence effect appeared despite financial incentives for accuracy, despite feedback training, and even in participants who had graduate training relevant to the task. Serial dependence could cause random error to be misattributed to real change, thereby leading to judgments that interventions are effective even when they are not.

Many older women experience the loss of a spouse or partner in later life. This paper explores older women's experiences of Christmas in order to locate process and meaning in relation to the transition of later life widowhood. Drawing on longitudinal data, derived from three in-depth interviews conducted over 18 months with 26 older widows, this paper presents a number of themes from the women's accounts of their Christmas celebrations and their Christmas cards. The importance of continuity, social relations and autonomy is situated in three emergent themes: ‘Family, intergenerational ties and tradition’, ‘Friendships, organisational ties and reciprocity’ and ‘Personal continuity and activation’. The significance of discontinuity, change and mediation is illustrated through three emergent themes: ‘Christmas as a catalyst for change’, ‘We are all widows’ and ‘Negotiating change with others’. The findings, including the positive aspects of continuity and discontinuity, demonstrate that Christmas is a potent symbol of both personal and social transformation during later life widowhood, and that the management of transition incorporates not only social relations, but also personal agency and flexibility. This paper further challenges the predominantly negative stereotype of older widows and illustrates their resilience and growth in the later stages of life.

This paper presents a physical investigation and mathematical analysis on mechanical behavior of the regular jugged discontinuity. In particular, we focus on the creep property of structural plane with various slope angles under different normal stress through shear creep tests of structural plane under shear stresses. According to the test results, the shear creep property of structural plane was described and the creep velocity and long-term strength of the structural plane during shear creep were also investigated. An empirical formula is finally established to evaluate shear strength of discontinuity and a modified Burger model was proposed to represent the shear deformation property during creep.

A semi-numerical method is derived to compute the Laplace transform of the equilibrium busy period probability density function in a fluid queue with constant output rate when the buffer is nonempty. The input process is controlled by a continuous-time semi-Markov chain (CTSMC) with n states such that in each state the input rate is constant. The holding time in states with net positive output rate - so-called emptying states - is assumed to be an exponentially distributed random variable, whereas in states with net positive input rate - so-called filling states - it may have an arbitrary probability distribution. The result is demonstrated by applying it to various systems, including fluid queues with two on-off input sources. The latter exercise in part shows consistency with prior results but also solves the problem in the case where there are two emptying states. Numerical results are presented for selected examples which expose discontinuities in the busy period distribution when the number of emptying states changes, e.g. as a result of increasing the fluid arrival rate in one or more states of the controlling CTSMC.

The simulation of simultaneous diffusion and precipitation of a chemical element during internal oxidation phenomena is presented here, from X-FEM method. This technique seems to be really appropriate when solubility products are very low, or even almost null. In this case, a precipitation front appears and should be properly represented by the numerical simulation. The X-FEM method is then of strong interest, since it allows to know precisely the position of the front all the time of simulation, without remeshing.

What happened at Vatican II and the significance of its decisions is strongly contested in the Church today. There is a struggle over the memory of the Council. It is suggested that two hermeneutics are in use, continuity versus discontinuity. On the one hand, it is said that privileging the ‘event’ of the Council as the interpretative key for reading its documents leads to an ideological distortion and introduces discontinuity with tradition. On the other hand, it is held that the continuity thesis plays down the real changes the Council introduced and, while unexceptional as a theological principle, it is being deployed as a polemical ideology, restricting necessary change. This article distinguishes between theological principle and experience in relation to continuity/discontinuity. It argues that the event of the Council is to be found as much in its effects in the Church at large as what took place in Rome. It analyses the phenomenology of change at both levels and concludes that the tensions between the need for continuity and the impulses of discontinuity need to be recognised and worked with rather than repressed.

Over the last quarter century, the dominant tendency in comparative cognitive psychology has been to emphasize the similarities between human and nonhuman minds and to downplay the differences as “one of degree and not of kind” (Darwin 1871). In the present target article, we argue that Darwin was mistaken: the profound biological continuity between human and nonhuman animals masks an equally profound discontinuity between human and nonhuman minds. To wit, there is a significant discontinuity in the degree to which human and nonhuman animals are able to approximate the higher-order, systematic, relational capabilities of a physical symbol system (PSS) (Newell 1980). We show that this symbolic-relational discontinuity pervades nearly every domain of cognition and runs much deeper than even the spectacular scaffolding provided by language or culture alone can explain. We propose a representational-level specification as to where human and nonhuman animals' abilities to approximate a PSS are similar and where they differ. We conclude by suggesting that recent symbolic-connectionist models of cognition shed new light on the mechanisms that underlie the gap between human and nonhuman minds.

Jump points in curves arise when the conditions under which data are generated change suddenly, for example because of an unplanned change in a treatment. This paper suggests bootstrap methods for quantifying the error in estimates of jump points, and for constructing confidence intervals for jump points and confidence bands for the curve. These problems have the unusual feature that the sampling error of the jump-point estimator often has a highly non-normal distribution, which depends intimately on the distribution of regression errors. The methods are illustrated by a simulation study as well as by an application to data on the annual flow volume of the Nile river.

This paper looks at the experience of bereavement in old age in a South Wales locality and traces the immediate and long-term effects it has on the bereaved. It examines various categories of bereavement – death of spouse, death of the mother, death of a child, siblings and friends, with death of spouse as specially significant. In each category it closely relates the experience of bereavement to the nature of the relationship formerly maintained, arguing that the significance of bereavement can only be appreciated within the context of social structure which defines the meaning of these relationships. It suggests that the special position occupied by female networks in the social structure enables old women to cope with the effects of bereavement more successfully than old men. For both old men and old women however, the special position they occupy with respect to contemporary society gives death a particular and unique resonance.