This study belongs to the ethnomethodological tradition of identifying the everyday practices accounting for the oiled machinery of social organization and applies this approach to understanding direction light usage. We observe a set of episodes videorecorded in North-East Italy in the urban traffic. We first unpack the meaning of direction light usage from a pragmatic perspective and then test our interpretation against the cases in our collection that seem to deviate from it. We argue that direction lights’ usage works as an announcement to some road users and a request to a subset of them; in both cases, direction lights convey contextualized (indexical) coordinates about the vehicle’s prospective trajectory. We then explain the cases in which signaling is omitted and draw some implications for traffic coordination and safety.

中文翻译：

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交通车辆之间的协调

这项研究属于民族方法论传统，即确定社会组织的日常实践，并将这种方法应用于理解方向灯的使用。我们在意大利东北部的城市交通中观察了一组录像片段。我们首先从实用的角度解释方向光使用的含义，然后根据我们收集的似乎偏离方向光的案例来测试我们的解释。我们认为，方向灯的使用起到了向某些道路使用者发出通知以及向其中一部分道路使用者发出请求的作用；在这两种情况下，方向灯都会传达有关车辆预期轨迹的上下文（索引）坐标。然后我们解释了信号被省略的情况，并得出了对交通协调和安全的一些影响。