Type I error rates from likelihood‐based repeated measures analyses of incomplete longitudinal data

The last observation carried forward (LOCF) approach is commonly utilized to handle missing values in the primary analysis of clinical trials. However, recent evidence suggests that likelihood‐based analyses developed under the missing at random (MAR) framework are sensible alternatives. The objective of this study was to assess the Type I error rates from a likelihood‐based MAR approach – mixed‐model repeated measures (MMRM) – compared with LOCF when estimating treatment contrasts for mean change from baseline to endpoint (Δ). Data emulating neuropsychiatric clinical trials were simulated in a 4 × 4 factorial arrangement of scenarios, using four patterns of mean changes over time and four strategies for deleting data to generate subject dropout via an MAR mechanism. In data with no dropout, estimates of Δ and SE_Δ from MMRM and LOCF were identical. In data with dropout, the Type I error rates (averaged across all scenarios) for MMRM and LOCF were 5.49% and 16.76%, respectively. In 11 of the 16 scenarios, the Type I error rate from MMRM was at least 1.00% closer to the expected rate of 5.00% than the corresponding rate from LOCF. In no scenario did LOCF yield a Type I error rate that was at least 1.00% closer to the expected rate than the corresponding rate from MMRM. The average estimate of SE_Δ from MMRM was greater in data with dropout than in complete data, whereas the average estimate of SE_Δ from LOCF was smaller in data with dropout than in complete data, suggesting that standard errors from MMRM better reflected the uncertainty in the data. The results from this investigation support those from previous studies, which found that MMRM provided reasonable control of Type I error even in the presence of MNAR missingness. No universally best approach to analysis of longitudinal data exists. However, likelihood‐based MAR approaches have been shown to perform well in a variety of situations and are a sensible alternative to the LOCF approach. MNAR methods can be used within a sensitivity analysis framework to test the potential presence and impact of MNAR data, thereby assessing robustness of results from an MAR method. Copyright © 2004 John Wiley & Sons, Ltd.     

Asset Decommissioning Risk Metrics for Floating Structures in the Gulf of Mexico

Public companies in the United States are required to report standardized values of their proved reserves and asset retirement obligations on an annual basis. When compared, these two measures provide an aggregate indicator of corporate decommissioning risk but, because of their consolidated nature, cannot readily be decomposed at a more granular level. The purpose of this article is to introduce a decommissioning risk metric defined in terms of the ratio of the expected value of an asset's reserves to its expected cost of decommissioning. Asset decommissioning risk (ADR) is more difficult to compute than a consolidated corporate risk measure, but can be used to quantify the decommissioning risk of structures and to perform regional comparisons, and also provides market signals of future decommissioning activity. We formalize two risk metrics for decommissioning and apply the ADR metric to the deepwater Gulf of Mexico (GOM) floater inventory. Deepwater oil and gas structures are expensive to construct, and at the end of their useful life, will be expensive to decommission. The value of proved reserves for the 42 floating structures in the GOM circa January 2013 is estimated to range between $37 and $80 billion for future oil prices between 60 and 120 $/bbl, which is about 10 to 20 times greater than the estimated $4.3 billion to decommission the inventory. Eni's Allegheny and MC Offshore's Jolliet tension leg platforms have ADR metrics less than one and are approaching the end of their useful life. Application of the proposed metrics in the regulatory review of supplemental bonding requirements in the U.S. Outer Continental Shelf is suggested to complement the current suite of financial metrics employed.     

Youth Style: Articulating cultural anxiety

In their everyday efforts to put together how they “look,” adolescents visually capture and articulate complex issues that society finds difficult to express verbally. In this paper we explore these “looks” as one example of youth appearance style and as a reflection of, and an impetus for, cultural anxieties. In doing so we draw on a series of multi‐method field studies conducted over the last ten years. A key feature of these studies has been the involvement of young people themselves as key informants and co‐investigators. Data from these studies can help clarify relationships between youth appearance style and cultural themes of sexuality and violence.     

Der Ebenenwechsel und seine Folgen Eine Gruppe experimentiert

Today, professionality is no longer safeguarded only by a specific professional membership. Particularly in the field of supervision, even organized supervisors have problems with quality safeguarding. For this reason the authors insist on a continuous reflection and development of concepts, and they report on their activities relating to this demand. The shift of level is a method of group dynamics based on the concept ”shift of perspectives“ in phenomenology.     

Vive la France! Vive la République? The Cultural Construction of French Identity at the World Exhibitions in Paris 1855–1900

Abstract

This article analyses how the world exhibitions were instrumentalised for national identity-building in 19th-century France. It argues that they probably strengthened a broadly consensual conception of a superior French culture and civilising mission. In contrast, it is doubtful whether the Second Empire and the Third Republic succeeded in hijacking them to sustain their political visions of the French nation. The exhibitions crystallised criticism of the two political systems, and vociferous debates about their nature and ideological content took place in the Republic. They also helped to strengthen other, sometimes conflicting identities, such as region and class, emphasising the cultural and political diversity of France.     

Unemployment Protection and Family Policy at the Turn of the 21st Century: A Dynamic Approach to Welfare Regime Theory

This article contributes to the welfare state regime literature from a substantive and methodological perspective. At a very abstract level we confirm the relevance of the welfare state regime theory and stability for the period from 1971 to the end of the 1990s. However, by analyzing family policy and unemployment protection, we observe a dual transformation of the welfare state, consisting of a trend towards a ‘socialization’ of family policies and a retrenchment in unemployment insurance benefits. Our Multiple Correspondence Analysis (MCA) of the two policy domains captures the multi‐dimensionality of the decommodification and defamilialization concepts and visualizes welfare state developments over time in a Cartesian space. This dynamic analysis provides us with a nuanced understanding of welfare state regime stability and change.     

One narrative or several? Politics,cultural elites,and citizens in constructing a ‘New Narrative for Europe’

ABSTRACT

European Union (EU) institutions have cultivated narratives of European integration for a long time. For its 2013–2014 ‘A New Narrative for Europe’ project, however, the European Commission for the first time explicitly used the ‘narrative’ label. Drawing on non-participant observation, semi-structured interviews and qualitative discourse analysis, this article contrasts the drafting process and the resulting declaration’s narrative structure and content with its discussion by citizens in a web-based consultation. The analysis shows that participating citizens forcefully demanded a bottom-up debate and advocated pluralistic perspectives. In these circumstances, elite-driven attempts at strengthening European identity and EU legitimacy are likely to be ineffective.