Other versions of negative utilitarianism differ in how much weight they give to negative well-being ('disutility') compared to positive well-being (positive utility), as well as the different conceptions of what well-being (utility) is. For example, negative preference utilitarianism says that the well-being in an outcome depends on frustrated preferences. Negative hedonistic utilitarianism thinks of well-being in terms of pleasant and unpleasant experiences.[6] There are many other variations on how negative utilitarianism can be specified.