Blocking in human causal learning is affected by outcome assumptions manipulated through causal structure     

Fernando Blanco  Frank Baeyens  Tom Beckers 《Learning & behavior》2014,42(2):185-199

Additivity-related assumptions have been proven to modulate blocking in human causal learning. Typically, these assumptions are manipulated by means of pretraining phases (including exposure to different outcome magnitudes), or through explicit instructions. In two experiments, we used a different approach that involved neither pretraining nor instructional manipulations. Instead, we manipulated the causal structure in which the cues were embedded, thereby appealing directly to the participants’ prior knowledge about causal relations and how causes would add up to yield stronger outcomes. Specifically, in our “different-system” condition, the participants should assume that the outcomes would add up, whereas in our “same-system” condition, a ceiling effect would prevent such an assumption. Consistent with our predictions, Experiment 1 showed that, when two cues from separate causal systems were combined, the participants did expect a stronger outcome on compound trials, and blocking was found, whereas when the cues belonged to the same causal system, the participants did not expect a stronger outcome on compound trials, and blocking was not observed. The results were partially replicated in Experiment 2, in which this pattern was found when the cues were tested for the second time. This evidence supports the claim that prior knowledge about the nature of causal relations can affect human causal learning. In addition, the fact that we did not manipulate causal assumptions through pretraining renders the results hard to account for with associative theories of learning.  相似文献   

Leading for Change: School Leader Advocacy for Undocumented Immigrant Students     

Emily R. Crawford  Danielle Walker  Fernando Valle 《Equity & Excellence in Education》2018,51(1):62-77

School leaders can ally with other educational stakeholders to encourage undocumented student persistence in Pk-12 schools. We explore (1) how school leaders create systems of support for undocumented and newly arrived immigrant students, and (2) how school leaders interpret and implement policies or school structures that affect student educational access. Border crossing theory guides our examination of how school leaders traverse and transgress borders that can impede students' education. This embedded case study included interviews with nine administrators working on the US-México border. The study finds that leaders expected to make a difference in students' lives by focusing on relationships and programming, committing to equity, and resisting deficit thinking about students and their families.  相似文献   

Physiological Correlations With Short,Medium, and Long Cycling Time-Trial Performance     

Fernando K. Borszcz  Artur F. Tramontin  Kristopher M. de Souza  Lorival J. Carminatti 《Research quarterly for exercise and sport》2018,89(1):120-125

Purpose: Several studies have demonstrated that physiological variables predict cycling endurance performance. However, it is still unclear whether the predictors will change over different performance durations. The aim of this study was to assess the correlations between physiological variables and cycling time trials with different durations. Methods: Twenty trained male cyclists (maximal oxygen uptake [VO₂max] = 60.5 ± 5.6 mL/kg/min) performed 4 separate experimental trials during a 2-week period. Cyclists initially completed an incremental exercise test until volitional exhaustion followed by 3 maximal cycling time trials on separate days. Each time trial consisted of 3 different durations: 5 min, 20 min, and 60 min performed in a randomized order. Results: The main results showed that the physiological measures strongly correlated with long cycling performances rather than short and medium time trials. The time-trial mean power output was moderately high to highly correlated with peak power output and VO_2max (r = .61–.87, r = .72–.89, respectively), and was moderately to highly correlated with the lactate threshold Dmax method and second ventilatory threshold (r = .52–.75, r = .55–.82, respectively). Conclusions: Therefore, trained cyclists should develop maximal aerobic power irrespective of the duration of time trial, as well as enhancements in metabolic thresholds for long-duration time trials.  相似文献