A common misapplication of statistical inference: nuisance control with null-hypothesis significance tests

Experimental research on behavior and cognition frequently rests on stimulus or subject selection where not all characteristics can be fully controlled, even when attempting strict matching. For example, when contrasting patients to controls, variables such as intelligence or socioeconomic status are often correlated with patient status. Similarly, when presenting word stimuli, variables such as word frequency are often correlated with primary variables of interest. One procedure very commonly employed to control for such nuisance effects is conducting inferential tests on confounding stimulus or subject characteristics. For example, if word length is not significantly different for two stimulus sets, they are considered as matched for word length. Such a test has high error rates and is conceptually misguided. It reflects a common misunderstanding of statistical tests: interpreting significance not to refer to inference about a particular population parameter, but about 1. the sample in question, 2. the practical relevance of a sample difference (so that a nonsignificant test is taken to indicate evidence for the absence of relevant differences). We show inferential testing for assessing nuisance effects to be inappropriate both pragmatically and philosophically, present a survey showing its high prevalence, and briefly discuss an alternative in the form of regression including nuisance variables

Evoked Potentials during Language Processing as Neurophysiological Phenomena

The evoked, event-related potential of the EEG has been extensively employed to study language processing. But what is the ERP? An extensive discussion of contemporary theories about the neurophysiology underlying late ERPs is given. Then, in a series of experiments, domain-general perspectives on ERP components are tested regarding their applicability for language-related brain activity. A range of analysis methods (some of which have not been previously applied to the study of auditory sentence processing) such as single-trial analyses and independent component decomposition, demonstrate the degree to which domain general mechanisms explain the language-related EEG

Feminist Development Policy: What does the Population think?

The continued lack of gender equality is an urgent global challenge. Against this backdrop, the German Federal Government announced in 2021 that it would include a feminist foreign policy in its coalition agreement. The aim of this policy is to strengthen the rights, representation and resources of women and marginalised groups and to promote the recognition of diversity. However, a feminist orientation in foreign and development policy meets with diverging views in political debate and provides cause for discussion in the (social) media. But what is the attitude of the general public? Aiming to answer this question, DEval examined public opinion on feminist development policy as part of its Opinion Monitor for Development Policy 2022. This Policy Brief summarises the results of the representative survey

Opinion Monitor for Development Policy 2021: Media content, information, appeals and their impact on public opinion

The DEval Opinion Monitor 2021 examines five key questions: (1) How often and in what way does the media report on the topic of development policy? (2) What impact do arguments for and against development cooperation used in the media have on the general public’s attitude towards the topic? (3) What impact does information on the effectiveness of development cooperation projects have on attitudes towards the topic? (4) What role do moral arguments and various foundations of morality play in attitudes towards the topic? (5) What expectations do citizens have of development cooperation? The report also explores how public opinion on development policy and on specific development policy measures has developed during the coronavirus pandemic. Therefor, the DEval Opinion Monitor 2021 gives development policy decision-makers feedback on the general public’s attitudes to development policy. The publication follows the Opinion Monitor for Development Policy 2018 and the Opinion Monitor for Development Policy 2019, which examined attitudes towards development cooperation and sustainable development in Germany (2018) and media use with a focus on international reporting and global poverty (2019)

Sustainable Consumption in the face of Global Challenges: Opportunities and Obstacles; Findings of the DEval Opinion Monitor for Development Policy 2022

Sustainable consumption contributes to sustainable global development. Due to the interdependencies between consumption behaviour in industrialised countries and people's living conditions in countries of the Global South, the issue is also highly relevant to development policy. Up to now, however, there is hardly any evidence with regard to the extent that citizens perceive their own consumption as having a global impact. The DEval Opinion Monitor for Development Policy 2022 looked into this question. This Policy Brief summarises the findings of the study

Priority effects in a planktonic bloom-forming marine diatom

Priority effects occur when a species or genotype with earlier arrival has an advantage such that its relative abundance in the community or population is increased compared with later-arriving species. Few studies have dealt with this concept in the context of within-species competition. Skeletonema marinoi is a marine diatom that shows a high degree of genetic differentiation between populations over small geographical distances. To test whether historical events such as priority effects may have been important in inducing these patterns of population differentiation, we performed microcosm experiments with successive inoculation of different S. marinoi strains. Our results show that even in the absence of a numerical advantage, significant priority effects were evident. We propose that priority effects may be an important mechanism in initiating population genetic differentiation

The Public's Expectations of Development Policy: Findings of the DEval Opinion Monitor for Development Policy 2021

This policy brief summarises the findings of the DEval Opinion Monitor for Development Policy 2021. It investigated which partner countries the general public perceives as particularly worthy of support and what socioeconomic and political characteristics of the countries are associated with this perception

Comparison of Spatial and Temporal Genetic Differentiation in a Harmful Dinoflagellate Species Emphasizes Impact of Local Processes

Population genetic studies provide insights into intraspecific diversity and dispersal patterns of microorganisms such as protists, which help understanding invasions, harmful algal bloom development and occurrence of seafood poisoning. Spatial genetic differentiation has been reported in many microbial species indicating significant dispersal barriers among different habitats. Temporal differentiation has been less studied and its frequency, drivers, and magnitude are thus relatively poorly understood. The toxic dinoflagellate species Gambierdiscus caribaeus was sampled during 2 years in the Florida Keys, and repeatedly from 2006 to 2016 at St. Thomas, US Virgin Islands (USVI), including a 3-year period with monthly sampling, enabling a comparison of spatial and temporal genetic differentiation. Samples from the USVI site showed high temporal variability in local population structure, which correlated with changes in salinity and benthic habitat cover. In some cases, temporal variability exceeded spatial differentiation, despite apparent lack of connectivity and dispersal across the Greater Caribbean Region based on the spatial genetic data. Thus, local processes such as selection might have a stronger influence on population structure in microorganisms than geographic distance. The observed high temporal genetic diversity challenges the prediction of harmful algal blooms and toxin concentrations, but illustrates also the evolutionary potential of microalgae to respond to environmental change

Meinungsmonitor Entwicklungspolitik 2021: Medieninhalte, Informationen, Appelle und ihre Wirkung auf die öffentliche Meinung

Der DEval-Meinungsmonitor 2021 befasst sich mit fünf zentralen Fragestellungen: (1) Wie häufig und wie wird über das Themenfeld Entwicklungspolitik in den Medien berichtet? (2) Welche Wirkung haben in den Medien genutzte Argumente für und gegen EZ auf die Einstellung der Bevölkerung zum Themenfeld? (3) Welche Wirkung haben Informationen zur Wirksamkeit von EZ-Projekten auf die Einstellung zum Themenfeld? (4) Welche Rolle spielen moralische Argumente und verschiedene Dimensionen von Moral für die Einstellung zum Themenfeld? (5) Welche Erwartungen haben die Bürger*innen an die EZ? Darüber hinaus wird beleuchtet, wie sich die öffentliche Meinung zu Entwicklungspolitik und zu konkreten entwicklungspolitischen Maßnahmen während der Corona-Pandemie entwickelt hat. Damit liefert dieser Bericht entwicklungspolitischen Entscheidungsträger*innen Orientierungswissen, um das Politikfeld und die Kommunikation mit der Bevölkerung auf Basis solider Informationen zu gestalten. Die Publikation schließt an den Meinungsmonitor Entwicklungspolitik 2018 und den Meinungsmonitor Entwicklungspolitik 2019 an, in denen die Einstellung der Bevölkerung zu EZ und nachhaltiger Entwicklung (2018) beziehungsweise die Mediennutzung mit Blick auf internationale Nachrichten und weltweite Armut (2019) untersucht wurden