Abstract. We present a study of people's use of positional information as part of a collaborative location-based game. The game exploits self-reported positioning in which mobile players manually reveal their positions to remote players by manipulating electronic maps. Analysis of players' movements, position reports and communications, drawing on video data, system logs and player feedback, highlights some of the ways in which humans generate, communicate and interpret position reports. It appears that remote participants are largely untroubled by the relatively high positional error associated with self reports. Our analysis suggests that this may because mobile players declare themselves to be in plausible locations such as at common landmarks, ahead of themselves on their current trajectory (stating their intent) or behind themselves (confirming previously visited locations). These observations raise new requirements for the future development of automated positioning systems and also suggest that selfreported positioning may be a useful fallback when automated systems are unavailable or too unreliable.

It is well-established finding that people find maps easier to use when they are aligned so that "up" on the map corresponds to the user's forward direction. With mapbased applications on handheld mobile devices, this forward/up correspondence can be maintained in several ways: the device can be physically rotated within the user's hands or the user can manually operate buttons to digitally rotate the map; alternatively, the map can be rotated automatically using data from an electronic compass. This paper examines all three options. In a field experiment, each method is compared against a baseline north-up condition. The study provides strong evidence that physical rotation is the most effective with applications that present the user with a wider map. The paper concludes with some suggestions for design improvements.

One of the most vivid aspects of consciousness is the experience of emotion, yet this topic is given relatively little attention within consciousness studies. Emotions are crucial, for they provide quick and motivating assessments of value, without which action would be misdirected or absent. Emotions also involve linkages between phenomenal and intentional consciousness. This paper examines emotional consciousness from the standpoint of the representational theory of consciousness (RTC). Two interesting developments spring from this. The first is the need for the representation of value, which is distinctive of emotional experience. The second is an extension of RTC's theory of introspection to emotional states, revealing why emotional consciousness is so often introspective even though introspective abilities are not needed to experience emotions, and also explaining why introspection of emotional states is so much less reliable than that of other states of consciousness.

Philosophers have traditionally drawn a sharp distinction between phenomenal and intentional states. Phenomenal states are states with phenomenal or subjective character -something it's like to be in them. The clearest examples of phenomenal states are perceptions, emotions, and sensations, which involve specific qualitative or sensory characters. Intentional states, such as beliefs, are mental states which represent something as being in a certain way. It has been commonly held that the intentional aspects of mental states lack phenomenal character while their phenomenal aspects lack intentionality. Modern representationalism about consciousness (MR) challenges this traditional distinction with the claim that phenomenal character is a species of and exhausted by representational content.

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