31. All earlier cases were decided with the negative externality of obscenity in mind. 32. Group 2 : it consists of services with strong externalities associated with them. 33. What about the cost of incorrectly calculating the true value of the externality ? 34. Classic textbook policy recommendation that deals with externalities includes variations of Pigouvian Tax. 35. Players may confront positive or negative externalities in networks. 36. One is the ability to control for externalities directly in the pricing mechanism. 37. MGMs could provide economic signals or incentives, for example in pricing externalities . 38. But there's not the slightest sign that we can internalize the externalities . 39. Externalities are a big part of environmental economics.40. Economists often urge the government to adopt policies that " internalize " an externality .