A Computer Model of Drafting Effects on Collective Behavior in Elite 10,000 m Runners

Purpose Drafting in cycling influences collective behaviour of pelotons. Whilst evidence for collective behaviour in competitive running events exists, it is not clear if this results from energetic savings conferred by drafting. This study modelled the effects of drafting on behavior in elite 10,000 m runners. Methods Using performance data from a men’s elite 10,000 m track running event, computer simulations were constructed using Netlogo 5.1 to test the effects of three different drafting quantities on collective behaviour: no drafting, drafting to 3m behind with up to ~8% energy savings (a realistic running draft); and drafting up to 3m behind with up to 38% energy savings (a realistic cycling draft). Three measures of collective behaviour were analysed in each condition; mean speed, mean group stretch (distance between first and last placed runner), and Runner Convergence Ratio (RCR) which represents the degree of drafting benefit obtained by the follower in a pair of coupled runners. Results Mean speeds were 6.32±0.28m.s-1, 5.57±0.18 m.s-1, and 5.51±0.13 m.s-1 in the cycling draft, runner draft, and no draft conditions respectively (all P<0.001). RCR was lower in the cycling draft condition, but did not differ between the other two. Mean stretch did not differ between conditions. Conclusions Collective behaviours observed in running events cannot be fully explained through energetic savings conferred by realistic drafting benefits. They may therefore result from other, possibly psychological, processes. The benefits or otherwise of engaging in such behavior are, as yet, unclear.

Exploring the Justificational Status of Assertions Made About Nursing’s Collective Beliefs

Nursing publications frequently reference groups (e.g. the group nurses). The nature and capabilities of group agents or collective subjects, and the relationship between nursing as a group and nurses as individuals is, however, rarely made explicit in these publications. Following Alvin Goldman, questions pertaining to groups can be classified as metaphysical or epistemic. Metaphysical questions take two forms. First, we might ask about the ontological status of group agents. For example, to what extent, if at all, do group agents exist and act independently of their constituent members? Second, we can ask whether group agents have psychological states or properties that can, for example, be formulated as propositional attitudes and, if they can, in what ways are group attitudes correlated with or tied to those of individual group members? In this presentation, having recognised the potential reality of group ontological and psychological being, I examine an under researched element of social epistemology. Specifically, the potential of non-individualist reliabilism (social process reliabilism) to justify doxastic group beliefs (i.e. statements such as “nurses believe that”) are considered. It is suggested that this issue has concrete implications for how we think about nursing.