ABSTRACT
The study of relationship closeness has a long history in psychology and is currently expanding across the social sciences, including economics. Estimating relationship closeness requires appropriate tools. Here, we introduce and test a tool for estimating relationship closeness: 'IOS11'. The IOS11 scale has an 11-point response scale and is a refinement of the widely used Inclusion-of-Other-in-the-Self scale. Our tool has three key features. First, the IOS11 scale is easy to understand and administer. Second, we provide a portable, interactive interface for the IOS11 scale, which can be used in lab and online studies. Third, and crucially, based on within-participant correlations of 751 individuals, we demonstrate strong validity of the IOS11 scale in terms of representing features of relationships captured by a range of more complex survey instruments. Based on these correlations we find that the IOS11 scale outperforms the IOS scale and performs as well as the related Oneness scale.
ABSTRACT
Friendship is commonly assumed to reduce strategic uncertainty and enhance tacit coordination. However, this assumption has never been tested across two opposite poles of coordination involving either strategic complementarity or substitutability. We had participants interact with friends or strangers in two classic coordination games: the stag-hunt game, which exhibits strategic complementarity and may foster "cooperation", and the entry game, which exhibits strategic substitutability and may foster "competition". Both games capture a frequent trade-off between a potentially high paying but uncertain option and a low paying but safe alternative. We find that, relative to strangers, friends are more likely to choose options involving uncertainty in stag-hunt games, but the opposite is true in entry games. Furthermore, in stag-hunt games, friends "tremble" less between options, coordinate better and earn more, but these advantages are largely decreased or lost in entry games. We further investigate how these effects are modulated by risk attitudes, friendship qualities, and interpersonal similarities.
ABSTRACT
Understanding the nature and influence of social relationships is of increasing interest to behavioral economists, and behavioral scientists more generally. In turn, this creates a need for tractable, and reliable, tools for measuring fundamental aspects of social relationships. We provide a comprehensive evaluation of the 'Inclusion of the Other in the Self' (IOS) Scale, a handy pictorial tool for measuring the subjectively perceived closeness of a relationship. The tool is highly portable, very easy for subjects to understand and takes less than 1 minute to administer. Across our three online studies with a diverse adult population (n = 772) we show that six different scales designed to measure relationship closeness are all highly significantly positively correlated with the IOS Scale. We then conduct a Principal Component Analysis to construct an Index of Relationship Closeness and find that it correlates very strongly (ρ = 85) with the IOS Scale. We conclude that the IOS Scale is a psychologically meaningful and highly reliable measure of the subjective closeness of relationships.
