Rolf Ulrich - Academia.edu (original) (raw)

Papers by Rolf Ulrich

Perspectives on psychological science : a journal of the Association for Psychological Science, 2016

In this article, we present a model for determining how total research payoff depends on research... more In this article, we present a model for determining how total research payoff depends on researchers' choices of sample sizes, α levels, and other parameters of the research process. The model can be used to quantify various trade-offs inherent in the research process and thus to balance competing goals, such as (a) maximizing both the number of studies carried out and also the statistical power of each study, (b) minimizing the rates of both false positive and false negative findings, and (c) maximizing both replicability and research efficiency. Given certain necessary information about a research area, the model can be used to determine the optimal values of sample size, statistical power, rate of false positives, rate of false negatives, and replicability, such that overall research payoff is maximized. More specifically, the model shows how the optimal values of these quantities depend upon the size and frequency of true effects within the area, as well as the individual pa...

Journal of sports sciences, 2016

The two major objectives of this study were (i) to assess variables that predict the use of analg... more The two major objectives of this study were (i) to assess variables that predict the use of analgesics in competitive athletes and (ii) to test whether the use of analgesics is associated with the use of doping. A questionnaire primarily addressing the use of analgesics and doping was distributed among 2,997 triathletes. Binary logistic regression analysis was performed to predict the use of analgesics. Moreover, the randomised response technique (RRT) was used to estimate the prevalence of doping in order to assess whether users of analgesics have a higher potential risk for doping than non-users. Statistical power analyses were performed to determine sample size. The bootstrap method was used to assess the statistical significance of the prevalence difference for doping between users and non-users of analgesics. Four variables from a pool of 16 variables were identified that predict the use of analgesics. These were: "version of questionnaire (English)", "gender (fe...

PLOS ONE, 2016

This study assessed the prevalence of physical and cognitive doping in recreational triathletes w... more This study assessed the prevalence of physical and cognitive doping in recreational triathletes with two different randomized response models, that is, the Cheater Detection Model (CDM) and the Unrelated Question Model (UQM). Since both models have been employed in assessing doping, the major objective of this study was to investigate whether the estimates of these two models converge. An anonymous questionnaire was distributed to 2,967 athletes at two triathlon events (Frankfurt and Wiesbaden, Germany). Doping behavior was assessed either with the CDM (Frankfurt sample, one Wiesbaden subsample) or the UQM (one Wiesbaden subsample). A generalized likelihood-ratio test was employed to check whether the prevalence estimates differed significantly between models. In addition, we compared the prevalence rates of the present survey with those of a previous study on a comparable sample. After exclusion of incomplete questionnaires and outliers, the data of 2,017 athletes entered the final data analysis. Twelve-month prevalence for physical doping ranged from 4% (Wiesbaden, CDM and UQM) to 12% (Frankfurt CDM), and for cognitive doping from 1% (Wiesbaden, CDM) to 9% (Frankfurt CDM). The generalized likelihood-ratio test indicated no differences in prevalence rates between the two methods. Furthermore, there were no significant differences in prevalences between the present (undertaken in 2014) and the previous survey (undertaken in 2011), although the estimates tended to be smaller in the present survey. The results suggest that the two models can provide converging prevalence estimates. The high rate of cheaters estimated by the CDM, however, suggests that the present results must be seen as a lower bound and that the true prevalence of doping might be considerably higher.

Journal of experimental psychology. General, 2015

Simonsohn, Nelson, and Simmons (2014) have suggested a novel test to detect p-hacking in research... more Simonsohn, Nelson, and Simmons (2014) have suggested a novel test to detect p-hacking in research, that is, when researchers report excessive rates of "significant effects" that are truly false positives. Although this test is very useful for identifying true effects in some cases, it fails to identify false positives in several situations when researchers conduct multiple statistical tests (e.g., reporting the most significant result). In these cases, p-curves are right-skewed, thereby mimicking the existence of real effects even if no effect is actually present. (PsycINFO Database Record

Experimental Psychology, 2016

The existence of a lateral mental timeline is well established; in left-to-right writing cultures... more The existence of a lateral mental timeline is well established; in left-to-right writing cultures, past is associated with the left, future with the right. Accordingly, participants respond faster with the left to past, and with the right to future. Recent studies indicate that this association does not reverse when participants respond with their hands crossed. We investigated the role of instruction for this association in a crossed-hands paradigm. Participants classified the temporal reference of words by pressing a key on the left with their right hand, or a key on the right with their left. Half of the participants were instructed to respond with their right or left hand; the other half were instructed to respond with the left or right key. An interaction between time and key showed only for participants instructed to respond with the key, providing support for the role of extracorporal space for the mental timeline.

Psychonomic Bulletin & Review, 2016

In line with ideomotor theory, numerous response-effect compatibility (REC) studies have revealed... more In line with ideomotor theory, numerous response-effect compatibility (REC) studies have revealed evidence that action effects are anticipated prior to action initiation, as indicated by an REC effect: For example, a response is given faster when its effect occurs on the same rather than on the opposite side. So far, REC studies have only investigated immediate effects-that is, effects occurring immediately after the response is given. However, it may be argued that in everyday life many actions cause effects that do not occur immediately. Additionally, because actions can have more than one effect, desired effects occurring in the future may only be arrived at if fundamental effects are achieved first. In the present study, we investigated whether temporally more distal effects are anticipated in order to initiate actions, and how multiple, serially occurring effects are represented. To this end, a spatial REC paradigm was extended in such a way that a first, immediate effect (i.e., immediately following the response; E1) was followed 500 ms later by another visual effect (E2). An REC effect was only observed for the temporally more distal E2, and this result suggests that temporally more distal effects can also be anticipated during action selection.

Acta psychologica, Jan 9, 2016

Rattat and Picard (2012) reported that the coding of temporal information in short-term memory is... more Rattat and Picard (2012) reported that the coding of temporal information in short-term memory is modality-specific, that is, temporal information received via the visual (auditory) modality is stored as a visual (auditory) code. This conclusion was supported by modality-specific interference effects on visual and auditory duration discrimination, which were induced by secondary tasks (visual tracking or articulatory suppression), presented during a retention interval. The present study assessed the stability of these modality-specific interference effects. Our study did not replicate the selective interference pattern but rather indicated that articulatory suppression not only impairs short-term memory for auditory but also for visual durations. This result pattern supports a crossmodal or an abstract view of temporal encoding.

ABSTRACT Einleitung: Mittels der Randomized Response Technique (RRT) konnten im Fitness- und Amat... more ABSTRACT Einleitung: Mittels der Randomized Response Technique (RRT) konnten im Fitness- und Amateursport hohe Prävalenzen für Arzneimittelmissbrauch und Illegalen Drogenkonsum zum expliziten Zweck der Leistungssteigerung (Doping) ermittelt werden. Die RRT ist eine Befragungsmethode, die den Befragten sowohl objektiv als auch subjektiv höchste Anonymität gewährleistet. Hierdurch wird die Bereitschaft, auf sensitive Fragen wahrheitsgemäß zu antworten, im Vergleich zu direkter Befragung erhöht. Die hier verwendete RRT-Variante des Cheater Detection Model (CDM) ermöglicht neben der Schätzung der Prävalenzrate des kritischen Verhaltens auch die Schätzung des Anteils instruktionswidrig Antwortender („Cheater“). Methoden: Mittels „paper-and-pencil“ Fragebogen wurden 2272 Amateurtriathleten bei 2 Wettkampfveranstaltungen (Frankfurt, Wiesbaden) befragt. Unter Anwendung des CDM wurde die 12-Monats-Prävalenz für geistiges und körperliches Doping geschätzt. Um motivationspsychologische Aspekte zu erfassen, ergänzten wir den Fragebogen mit der Wettbewerbsorientierungsskala des Leistungsmotivationsinventars. Zusätzlich wurden deskriptive Daten sowie trainingsmethodische Variablen erfasst. Ergebnisse: Die Datenerhebung ergab, nach Ausschluss unvollständig ausgefüllter Fragebögen und Ausreißern, einen Rücklauf von 1449 (63,8%) Fragebögen. Die geschätzte 12-Monats-Prävalenz für die Einnahme von Substanzen zur geistigen Leistungssteigerung lag bei 9,4% (Frankfurt) und 1,6% (Wiesbaden), die der körperlichen Leistungssteigerung lag bei 11,9% (Frankfurt) und 3,5% (Wiesbaden). Der geschätzte Anteil von „Cheatern“ lag in Frankfurt bei 59,1% (geistige Leistungssteigerung) und 64,9% (körperliche Leistungssteigerung). In Wiesbaden ergaben sich hierfür 45,8% und 53,3%. Es zeigte sich kein Zusammenhang zwischen Doping und Wettbewerbsorientierung. Diskussion: Die Ergebnisse dieser Studie zeigen, dass auch der Amateursport nicht frei von Doping ist. Der geschätzte Anteil von „Cheatern“ spricht darüber hinaus dafür, dass auch mittels RRT ermittelte Prävalenzen dieses Phänomen unterschätzen. Um Präventionsmaßnahmen effektiver zu gestalten und weiterzuentwickeln, müssen die Beweggründe für Doping im Amateursport weiter erforscht werden.

Atten Percept Psychophys, 2004

Http Dx Doi Org 10 1080 17470210701536419, Nov 6, 2007

Temporal preparation often has been assumed to influence motor stages of information processing. ... more Temporal preparation often has been assumed to influence motor stages of information processing. Recent studies, however, challenge this notion and provide evidence for a facilitation of visual processing. The present study was designed to investigate whether perceptual processing in the auditory domain also benefits from temporal preparation. To this end, we employed a pitch discrimination task. In Experiment 1, discrimination performance was clearly improved when participants were temporally prepared. This finding was confirmed in Experiment 2, which ruled out possible influences of short-term memory. The results support the notion that temporal preparation enhances perceptual processing not only in the visual, but also in the auditory, modality.

Perception and Psychophysics, Nov 1, 2008

Folia Microbiol Prague, 1998

Atten Percept Psychophys, Jun 1, 2004

Four experiments were conducted in order to compare the effects of stimulus redundancy on tempora... more Four experiments were conducted in order to compare the effects of stimulus redundancy on temporal order judgments (TOJs) and reaction times (RTs). In Experiments 1 and 2, participants were presented in each trial with a tone and either a single visual stimulus or two redundant visual stimuli. They were asked to judge whether the tone or the visual display was presented first. Judgments of the relative onset times of the visual and the auditory stimuli were virtually unaffected by the presentation of redundant, rather than single, visual stimuli. Experiments 3 and 4 used simple RT tasks with the same stimuli, and responses were much faster to redundant than to single visual stimuli. It appears that the traditional speedup of RT associated with redundant visual stimuli arises after the stimulus detection processes to which TOJs are sensitive.

$Research paper thumbnail of The locus of temporal preparation effects: Evidence from the psychological refractory period paradigm$

Psychonomic Bulletin Review, Jun 1, 2006

Experimental Psychology, Feb 27, 2015

Previous reaction time studies have demonstrated coactivation processes within the visual modalit... more Previous reaction time studies have demonstrated coactivation processes within the visual modality for redundant stimuli that differ in two dimensions (e.g., shape and color). The present study provides novel results of analogous processes within the auditory modality. A redundant-target effect (RTE) was obtained in a Go/NoGo experiment using tones that differed in location and/or frequency. Participants were asked to respond to a specific tone location (e.g., left) and/or tone frequency (e.g., 200 Hz) of auditory stimuli. For redundant targets (e.g., a 200 Hz tone presented to the left), an RTE was observed which was too large to be explained by mere statistical facilitation. Therefore, responses to redundant targets were triggered by a combined activation of the target dimensions. The results are consistent with the modular hybrid account of Mordkoff and Yantis (1993).

Http Dx Doi Org 10 1080 13506280143000548, Oct 1, 2010

ABSTRACT

Acta Psychologica, May 1, 2011

The distinct timing hypothesis suggests a sensory mechanism for processing of durations in the ra... more The distinct timing hypothesis suggests a sensory mechanism for processing of durations in the range of milliseconds and a cognitively controlled mechanism for processing of longer durations. To test this hypothesis, we employed a dual-task approach to investigate the effects of maintenance and elaborative rehearsal on temporal processing of brief and long durations. Unlike mere maintenance rehearsal, elaborative rehearsal as a secondary task involved transfer of information from working to long-term memory and elaboration of information to enhance storage in long-term memory. Duration discrimination of brief intervals was not affected by a secondary cognitive task that required either maintenance or elaborative rehearsal. Concurrent elaborative rehearsal, however, impaired discrimination of longer durations as compared to maintenance rehearsal and a control condition with no secondary task. These findings endorse the distinct timing hypothesis and are in line with the notion that executive functions, such as continuous memory updating and active transfer of information into long-term memory interfere with temporal processing of durations in the second, but not in the millisecond range.