One of the most useful features of goal models of the i* family is their ability to represent and reason about satisfaction influence of one goal to another. This is done through contribution links, which represent how satisfaction or denial of the origin of the link constitutes evidence of satisfaction/denial of its destination. Typically in the i* family, the nature and level of contribution is represented through qualitative labels ("+", "−", "++" etc.), with the possibility of alternatively

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... using numeric values, as per various proposals in the literature. Obviously, our intuition seems to suggest, labels are easier to comprehend and to come up with, while the use of numbers raises the question of where they come from and what they mean, adds unwarranted precision and overwhelms readers. But are such claims fair? Based on some early experimental results, we make the case for more empirical work on the matter in order to better clarify the differences and understand how to use contribution representations more effectively.