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Marlies Stockmann - One of the best experts on this subject based on the ideXlab platform.
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das kolonisationsgeschehen auf den jungen nordseeinseln Memmert und mellum am beispiel der zikaden hemiptera fulgoromorpha et cicadomorpha
Cicadina, 2014Co-Authors: Marlies Stockmann, Rolf NiedringhausAbstract:Abstract: The colonisation process of Auchenorrhyncha on the North Sea dune islands of Memmert and Mellum. – A decade after our first study an inventory control of the Auchenorrhyncha fauna on the North Sea dune islands of Memmert and Mellum was made in 1994 and 1995. On both islands the assessed species number has remained nearly constant. On Memmert 12 species were recorced as new, among them two new records for the chain of East Frisian islands. For Mellum there were 10 new records. With a rate of 18 and 20 %, respectively, the species turnover is low compared to other arthropod groups. These findings are mostly due to temporary colonist species. The remaining part can be assigned to changes in habitat parameters (particularly an increase in shrub growth) or flaws in the sampling. However, a stochastic species turnover in terms of the equilibrium theory cannot be substantiated. Key words: Auchenorrhyncha, North Sea islands, species turnover, island biogeography
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das kolonisationsgeschehen auf den jungen nordseeinseln Memmert und mellum am beispiel der zikaden
2004Co-Authors: Marlies StockmannAbstract:Kurzfassung: Zehn Jahre nach einer Erstuntersuchung wurde 1994 und 1995 eine erneute Arteninventur der Zikadenfauna auf den jungen Nordsee-Duneninseln Memmert und Mellum durchgefuhrt. Auf beiden Inseln war die Artenzahl annahernd gleich geblieben. Auf Memmert wurden 12 Arten neu festgestellt; darunter waren auch zwei Neufunde fur die gesamten Ostfriesischen Inseln. Auf Mellum gab es 10 Neufunde. Mit einer Rate von 18 bzw. 20 % war der Arten-Turnover gering im Vergleich mit anderen Arthropodengruppen. Diese Befunde sind grostenteils durch temporare Kolonisten zu erklaren, auserdem durch Habitatveranderungen, insbesondere Gebuschaufwuchs, sowie durch Erfassungsmangel. Allerdings kann ein stochastischer Arten-Turnover im Sinne der Equilibrium-Theorie nicht bestatigt werden.
Daniel Memmert - One of the best experts on this subject based on the ideXlab platform.
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Game Intelligence Analysis by Means of a Combination of Variance-Analysis and Neural Networks.
2020Co-Authors: Daniel Memmert, Jürgen PerlAbstract:In order to evaluate performance data from games, normally qualitative and quantitative methods are used separately. The aim of this contribution is to demonstrate that the combination of net-based qualitative analyses and stochastic quantitative analyses can improve the information output significantly. The stochastic approach reduces the total of recorded data to only a few statistical quantities, which are not necessarily data-specific. In contrast, neuronal networks – considering data to be high-dimensional points that correspond to neurones – can (e.g.) be used to extract specific striking features on the original data (see Schollhorn & Perl, 2002). This approach will exemplarily be demonstrated using data from a BISpsponsored project that was run by Roth and Memmert (2003). In this field-study, sport-specific training concepts were compared with non-specific ones, dealing (e.g.) with the game intelligence of about 150 children from two measuring points (MZP). The convergent reference numbers were determined by means of concept-oriented expert ratings (3 evaluators) using three game-test-situations with two rotations each (see Memmert & Roth, 2003). Using dynamical adaptive neural networks ("DyCoN"; Perl, 2000) allows for simultaneous processing of 12-dimensional attribute vectors (2 MZP x 3 evaluator x 2 rotations) instead of 2-dimensional aggregated vectors – avoiding reduction of semantic structures and information. This way, by means of visual evaluation of data distribution projected to the net structure analysis of interand intra-individual correspondences useful information become available which can hardly or not be obtained from variance-analyses. The existing evaluations suggest that DyCoN, similar to the case of convergent performance attributes, will also be successful in the divergent case.
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Tactics Analysis in Soccer - An Advanced Approach
2020Co-Authors: Jürgen Perl, Andreas Grunz, Daniel MemmertAbstract:In order to run a game tactically, high level knowledge is required from and by coaches and analysis experts. Assessing tactical performance through statistic indicators has some drawbacks, however, it is not only difficult to prove reliability on the defined indicators, but those static indicators often hide the game's dynamics. New network-based approaches offer a promising way to improve future evaluation of tactical performance and recognition of game dynamics. The aim of this article is to introduce a new approach where patternbased tactics analysis is combined with success-oriented statistical frequency analysis. Therefore, the neural network-based pattern analysis of the SOCCERapproach (Perl & Memmert, 2011) has been completed by an event-oriented statistical analysis, which is mainly based on an automatic recognition of ball possession as an indicator of success. After a short introduction into basic aspects of game analysis, automatic position tracking and net-based pattern analysis, the new concept of SOCCER is presented in two steps: The first part deals with netbased analysis of dynamic processes, oriented in constellations of tactical groups of players. The second part deals with rule based semantics analysis, which allows automatic recognition and evaluation of individual activities and embedding them into the tactical patterns - thus enabling both, evaluation of tactical processes based on individual success as well as evaluation of individual activities in the context of tactical processes.
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Perceptual-cognitive processes underlying creativity in skilled soccer players
2017Co-Authors: André Roca, Daniel Memmert, Paul R. FordAbstract:Introduction Creativity is a divergent thinking ability to produce varying, original, and flexible solutions across different situational contexts (Memmert et al., 2007). It forms a key part of expert performance in soccer and other domains. The aim of this study was to determine the underlying perceptual and cognitive processes that underpin superior creative performance in soccer players. Methods Forty skilled adult soccer players participated. In the experimental task they viewed life-size video of 11 vs. 11 attacking situations whilst in possession of a ball. Clips were occluded at a key moment and they were required to play the ball in response to each situation. Moreover, they were required to verbalize the additional actions they could execute for each situation. Their solutions on the task were measured using the three observation criteria for creativity of originality, flexibility, and fluency of decisions. Players were categorized using these criteria into either more- or less-creative groups. Visual search and cognitive processes were recorded during the task using a portable eye-movement registration system and retrospective verbal reports, respectively. Results & Discussion The creativity-based between-group differences in decision making were underpinned by differences in visual search strategy. Creative players made more fixations of shorter duration in a different sequential order and towards more informative locations of the display compared with less-creative players, indicating a broader attentional focus. They generated a greater number of verbal report statements related to assessment of the current situation and planning of future actions when compared with the less-creative players. Our findings highlight the perceptual-cognitive processes underlying superior creative performance in soccer. Conclusion Creative performance in soccer players is underpinned by perceptual-cognitive processes that appear to be crucial in facilitating more novel solutions.
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“How Much is that Player in the Window? The One with the Early Birthday?” Relative Age Influences the Value of the Best Soccer Players, but Not the Best Businesspeople
Frontiers in Psychology, 2016Co-Authors: Philip Furley, Daniel Memmert, Matthias WeigeltAbstract:Although people in general tend to attribute success to individual merit (see e.g., Gilbert and Malone, 1995) research has shown that something as trivial as the date of a person's birth can have—under certain circumstances—a major impact on an individual's achievement. The Canadian psychologist Roger Barnsley (Barnsley et al., 1985) made the extraordinary discovery that the great majority of top-level athletes were born within the first months of the year, whereas a lot less players playing at the highest level were born later in the year (Dudink, 1994; Edwards, 1994; Cobley et al., 2009). This skewed birthdate distribution was termed Relative Age Effect. The assumed explanation for this effect was simple and had nothing to do with Astrology, but instead was attributed to the fact that children and youth athletes are divided into age-groups according to their birth date (usually with the cutoff date being the first of January). This early selection cutoff date can lead to a maturation head start of almost a year within an age group. It is further assumed that this maturation head start will result in a Matthew effect (“the rich get richer; the poor get poorer,” see e.g., Merton, 1957) due to better developmental circumstances, such as better coaching, more playing and practice time. Indeed, research suggests that coaches have more favorable attitudes toward more matured players (Furley and Memmert, 2015) and that maturation advantages have the potential to translate to performance advantages (Buchheit and Mendez-Villanueva, 2014; Gastin and Bennett, 2014). As a consequence, the most successful athletes are likely to show a skewed birthdate distribution (see e.g., Helsen et al., 2012 for a recent demonstration), whereas success in other domains without early selection processes involving cutoff dates should not show a skewed birthdate distribution as individuals have equal opportunities to develop (Barnsley et al., 1985). To date Relative Age Effects have almost exclusively been shown within high achieving cohorts, such as national teams or within the highest levels of competitive sport, while it remains unclear whether birthdates also have the potential to translate to monetary value. Therefore, we tested for Relative Age Effects within the 100 most valuable soccer players according to their 2015 CIES (Poli et al., 2015) estimated transfer values (high achievement group with early selection cutoff date) and within the 100 richest billionaires according to their Forbes Net Value (high achievement group without early selection cutoff date). See Supplemental Material and Author Note for more detail on the analyzed sample. As expected, we found that amongst the 100 most valuable soccer players 60% were born in the first half of the year (Mvalue = 48.3 million $; SDvalue = 41.1 million $), whereas 40% (Mvalue = 39.8 million $; SDvalue = 15.1 million) were born in the second half, which differed significantly form the expected even distribution [χ(1, N=100)2=4.000; p = 0.023, one-tailed; OR = 1.50 (0.86, 2.62); see Figure Figure1].1]. Although, players born in the first half of the year were worth approximately 8 Million $ more, this effect only approached significance [t(80.380)=1.472, p = 0.07, one-tailed; d = 0.30 (–0.10, 0.70)]. Importantly, no such skewed distribution was evident amongst the 100 highest ranked Forbes billionaires [χ(1,N=100)2=0.040; p = 0.841, two-tailed; OR = 0.96 (0.55, 1.67)] with 49% being born in the first half year (Mnetvalue = 22.0 billion$; SDnetvalue = 13.3 billion) and 51% (Mnetvalue = 23.0 billion$; SDnetvalue = 14.3 billion) in the second half year. Comparative analysis of both the soccer and the Forbes distribution revealed a significant difference between the birthdate distributions of the 100 most valuable—in monetary terms—soccer players and businesspeople [χ(1, N=100)2=6.829; p = 0.008, one-tailed; OR = 1.56 (0.89, 2.73)]. Figure 1 Distributions of the 100 most valuable soccer players and billionaires as a function of half year in which they were born. The dotted line represents the expected even distribution. The text within the bars shows the mean value of the respective groups. ... The present analysis shows that birthdates—under certain circumstances (early selection cutoff dates)—not only have the potential to open up gates to high achieving cohorts, but can actually result in higher monetary value (but see Ashworth and Heyndels, 2007, for differences in actual earnings). While the division of children into age groups based on their birth-date has the well-meant intention to provide equal opportunities for participation and success, paradoxically this is not the case as there is a systematic exclusion of children born further away from the cutoff date (usually later in the year if the cutoff date is the 1st of January). Here, it is important to note that Relative Age Effects have also been found in the broader educational system (Pidgeon, 1965), albeit the pattern is not very consistent across studies (e.g., Jeronimus et al., 2015 for a recent investigation). Of further relevance, Matsubayashi and Ueda (2015) argued that relative younger students seem to take less desirable career paths that might be associated with poorer psychological health compared to students with a relative age advantage. In this respect, we hope to add a further line of argumentation against highly-selective developmental and education systems beginning at early ages based on birthdates as people in domains that arguably are not affected (e.g., business) by early selection cutoff dates have the potential of doing equally well. Taken together, early selection cutoff dates have broad implications that need to be taken seriously by political decision makers in order to meet the goal of providing equal opportunities to people.
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Beyond inattentional blindness and attentional misdirection: From attentional paradigms to attentional mechanisms ☆
Consciousness and Cognition, 2010Co-Authors: Daniel Memmert, Philip FurleyAbstract:Memmert (2010) tried to foster the development of attentional research by discussing four differences between attentional misdirection (AM) and inattentional blindness (IB). Considering this goal, the comment was received in the intended way by the comments of Most (2010) and Moran and Brady (2010) who make a number of highly valuable suggestions for further progress. As initially suggested by Memmert (2010) this dialog should help unravel the underlying attentional mechanisms of different paradigms. Therefore, we first discuss the suggested distinction between central and spatial IB by Most (2010). Second, we argue that working memory and perceptual load research seem particularly interesting in this regard and should be taken into consideration when conducting future research along the lines of IB and AM. Third, representative task designs can be an important mosaic piece in across-the-board attention theories and highly useful for deriving further testable hypothesis in naturalistic settings. The most important claim of all commentaries in this issue is that the proposed ideas can all be empirically tested and thereby contribute to the advancement of an unified theoretical framework incorporating IB, AM in consideration of overt and covert attention mechanisms.
Rolf Niedringhaus - One of the best experts on this subject based on the ideXlab platform.
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das kolonisationsgeschehen auf den jungen nordseeinseln Memmert und mellum am beispiel der zikaden hemiptera fulgoromorpha et cicadomorpha
Cicadina, 2014Co-Authors: Marlies Stockmann, Rolf NiedringhausAbstract:Abstract: The colonisation process of Auchenorrhyncha on the North Sea dune islands of Memmert and Mellum. – A decade after our first study an inventory control of the Auchenorrhyncha fauna on the North Sea dune islands of Memmert and Mellum was made in 1994 and 1995. On both islands the assessed species number has remained nearly constant. On Memmert 12 species were recorced as new, among them two new records for the chain of East Frisian islands. For Mellum there were 10 new records. With a rate of 18 and 20 %, respectively, the species turnover is low compared to other arthropod groups. These findings are mostly due to temporary colonist species. The remaining part can be assigned to changes in habitat parameters (particularly an increase in shrub growth) or flaws in the sampling. However, a stochastic species turnover in terms of the equilibrium theory cannot be substantiated. Key words: Auchenorrhyncha, North Sea islands, species turnover, island biogeography
Benjamin Messner - One of the best experts on this subject based on the ideXlab platform.
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die sagekafer coleoptera heteroceridae auf denostfriesischen inseln Memmert und mellum
2001Co-Authors: Benjamin MessnerAbstract:Mit Hilfe von Bodenfallen- und Farbschalen-Fangen konnte gezeigt werden, das die Sagekafer bis jetzt nur mit einer einzigen Art (Heterocerus flexuosus) die ca. 100 Jahre jungen ostfriesischen Inseln Memmert und Mellum besiedelt haben. – Die Jahresaktivitat dieser Heterocerus-Art ist nur dann sicher feststellbar, wenn die Bodenfallen exakt an den Stellen aufgestellt werden, wo sich die Fras- und Brutgange befinden; anderenfalls sind nur Einzelfange zu erwarten.
Roland Seiler - One of the best experts on this subject based on the ideXlab platform.
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Influence of body language on penalty takers' performance
2018Co-Authors: Kirstin Seiler, Geoffrey Schweizer, Roland SeilerAbstract:Previous research on nonverbal behavior (NVB) in the sport performance setting (Furley, Moll, & Memmert, 2015; Greenlees, Leyland, Thelwell, & Filby, 2008) has shown that NVB might be among the most important factors influencing emotions and outcome expectations. However, research on NVB so far has neglected to conduct studies in non-experimental settings and to measure the behavioral consequences of NVB. Thus, following the call from Baumeister, Vohs, and Funder (2007), it was the aim of the present research to realize a field study (i.e., a real-world soccer penalty scenario) and to not only measure subjective questionnaire variables (i.e., outcome expectations) but also performance variables (i.e., precision and speed of the kicks) as consequences of NVB. Each of N = 47 male experienced soccer players took 20 penalties, alternating against one dominant and one submissive goalkeeper, manipulated using instructions from experimental studies. The reactions of the goalkeepers (left vs. right) were randomised and the NVB of the goalkeepers was changed after each participant. Before the shootout, participants filled in a questionnaire on outcome expectations when watching the goalkeepers. During the shootout, precision and speed of each kick was measured using GoPro Hero2-cameras. First results show that both goalkeepers were rated stronger when showing dominant NVB compared to submissive NVB. Further, the dominant goalkeeper was perceived stronger than the submissive one. However, the NVB of the goalkeepers did not significantly influence the outcome expectations of the penalty takers. Further analyses will show whether NVB influences objective performance measurements of precision and speed. Our results concerning subjective outcome variables do not confirm previous laboratory research on NVB as we could not find an effect of NVB on outcome expectations. This discrepancy between previous laboratory research and the results of this study show the importance of conducting field studies and of measuring real behavior.
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Influences of stereotypes on the relation between nonverbal behaviour and team confidence in soccer
2018Co-Authors: Kirstin Seiler, Geoffrey Schweizer, Roland SeilerAbstract:Theoretical Background. Previous research on nonverbal behaviour (NVB) in the sport performance setting (Furley, Moll, & Memmert, 2015; Greenlees, Leyland, Thelwell, & Filby, 2008) has shown that NVB might be among the most important factors influencing emotions and team confidence within sport teams. Even when objective performance information was included as another potential factor influencing the person perception process the NVB-effect remained large (Seiler, Schweizer, & Seiler, 2017). However, research on NVB so far has not considered the influence of subjective performance information such as gender stereotypes on the soccer abilities of men and women although stereotypes seem to be crucial for the person perception process (see Kunda & Thagard, 1996, for a review). Research question. The aim of the present research was to investigate whether the effects of nonverbal behaviour (NVB) on team outcome confidence in sports decrease when subjective performance information transported through gender stereotypes is added. Method. Using video footage of football players as stimulus material, two experiments were designed (Experiment 1 with sports science students, N = 59, and Experiment 2, N = 59, with members of a football club) to examine the effects of both NVB and subjective performance information on team outcome confidence. Results. In both experiments, a 2 x 2 gender [male vs. female] x NVB [dominant vs. submissive] repeated measures ANOVA was conducted to test the influence of gender. The results of Experiment 1 showed that from the teammate’s perspective, the NVB-effect remained large when gender is included. However, gender also had a significant influence on team outcome confidence. When the potential teammate was a woman, team outcome confidence was generally lower than when the teammate was male. Still, the interaction between NVB and gender was not significant, meaning that the influence of gender was not sufficiently large that it reversed the influence of NVB. The results from the opponent’s perspective where reversed. Even in Experiment 2 in which the stereotype was more present the NVB-effect remained strong. Discussion. Our results are in line with previous research on person perception and NVB in sports as they suggest that several factors have an influence on the person perception process but also that the NVB-effect remains large even when further information is provided.
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Body language takes it all? – Effects of Nonverbal Behavior and players‘ ability level on outcome expectations in team sports
2017Co-Authors: Kirstin Seiler, Geoffrey Schweizer, Roland SeilerAbstract:Introduction Studien zeigen, dass Nonverbales Verhalten (NVV) im Sport – beispielsweise Dominanz und Unterwurfigkeit – u.a. Einschatzungen uber leistungsrelevante Charakteristika (Furley, Moll, & Memmert, 2015) und die Erfolgserwartung von Beobachtenden (Furley, Dicks, & Memmert, 2012) beeinflusst. Eine mogliche Erklarung konnte die schemabasierte Verarbeitung von Informationen sein, welche dazu beitragt, dass Dominanz mit positiven, Unterwurfigkeit dagegen mit negativen Eigenschaften assoziiert wird (Furley et al., 2012). Diese Studien wurden jedoch in einem kunstlichen Setting durchgefuhrt, in welchem demand-Effekte eine wichtige Rolle fur die grossen Effektstarken und die schemabasierte Informationsverarbeitung spielen konnten. Ziel der zweiteiligen Experimentalstudie war es zu prufen, inwieweit sich Teamsportler vom NVV ihrer Mitspieler und des Gegners beeinflussen lassen, wenn ihnen zusatzlich objektive Informationen zur Spielerqualitat und damit Optionen zu einer datengetriebenen Informationsverarbeitung zur Verfugung stehen. Methods Fur beide Experimente wurden 24 Videos erstellt, in welchen sich je 12 mannliche und 12 weibliche Fussballer jeweils in einer dominanten und einer unterwurfigen Korperhaltung personlich vorstellen. In Experiment 2 erhielten die Teilnehmer zusatzlich zu Variationen in der Korpersprache entweder positive oder negative Informationen (hohe oder niedrige Punktzahl) uber die Qualitat des Spielers im Video. N = 80 Sportstudierende in Experiment 1 und N = 61 Sportstudierende in Experiment 2 sahen in einem vollstandig randomisierten Design jeweils sechs dominante und sechs unterwurfige Videos ihres entsprechenden Geschlechts. Auf einer 11-stufigen Skala von 0%-100% zuversichtlich mussten sie angeben, wie zuversichtlich sie sind, mit ihrem Team in einem anstehenden Aufstiegsspiel zu gewinnen, wenn der Spieler im Video in den Mannschaftskader des eigenen oder des gegnerischen Teams berufen werden wurde. Results In Experiment 1 zeigt eine 2 (NVV: dominant, unterwurfig) x 2 (Perspektive: Mitspieler, Gegenspieler) ANOVA mit Messwiederholung auf beiden unabhangigen Variablen, dass die Erfolgszuversicht in der dominanten Bedingung signifikant hoher ist als in der unterwurfigen Bedingung, wenn der Spieler im Video ein Mitspieler ist, die Erfolgszuversicht in der dominanten Bedingung dagegen signifikant niedriger ist als in der unterwurfigen Bedingung, wenn der Spieler im Video ein Gegner ist. Eine messwiederholte 2 (NVV: dominant, unterwurfig) x 2 (Perspektive: Mitspieler, Gegenspieler) x 2 (Spielerqualitat: positiv, negativ) ANOVA in Experiment 2 zeigte einen signifikanten Interaktionseffekt und grosse Effektstarken fur die Interaktion Perspektive x Informationen, die Interaktion Perspektive x Korpersprache war dagegen im Unterschied zu Experiment 1 nicht mehr signifikant. Die Erfolgszuversicht ist also signifikant hoher, wenn positive Informationen uber einen Mitspieler oder negative Informationen uber einen Gegner gegeben werden. Discussion/Conclusion Die Ergebnisse bestatigen bisherige Befunde zur Bedeutung von NVV. Denn Korpersprache hat einen entscheidenden Einfluss auf die Erfolgszuversicht, wenn nur ein Kriterium zur Entscheidungsfindung zur Verfugung steht. Bei Erganzung des objektiven Kriteriums der Spielerqualitat wird die Erfolgszuversicht von Sportteams dagegen vor allem durch dieses Kriterium bestimmt, die Korpersprache spielt keine entscheidende Rolle mehr. Zukunftige Forschung sollte weitere Faktoren untersuchen, welche den Zusammenhang zwischen NVV und Erfolgszuversicht beeinflussen konnen. Praktische Implikationen werden diskutiert.