While economic sociology research and theory argue that excessive network embeddedness depresses competition in illegal markets, prior research does not examine how distinct types of embeddedness may have asymmetric effects on the diversity of purchasing behavior—the range of illegal goods that buyers typically purchase. This study considers how network embeddedness can positively or negatively affect drug purchasing diversity in online drug markets by referring buyers to new vendors or “locking” buyers into recurrent trade for the same products. We analyze novel network data on 16,847 illegal drug exchanges between 7205 actors on one online illegal drug market. Consistent with hypothesized network asymmetry, buyers are more likely to purchase a new type of drug when the transaction is part of an indirect network referral. Although histories of exchange increase the overall frequency of drug purchasing, they are associated with decreases in new drug-type purchases. In the aggregate, these processes either contribute to an integrated market where buyers purchase multiple drugs from multiple vendors (in the case of referrals) or a fragmented market characterized by recurrent trade from the same vendors for the same substances (in the case of repeated trade). We discuss the implications of these findings for research on embeddedness, illegal markets, risky exchange, and drug policy.

中文翻译：

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嵌入性的不对称：网络非法药品市场上的非法交易网络与药品采购多样性

虽然经济社会学研究和理论认为，过度的网络嵌入会抑制非法市场的竞争，但先前的研究并没有研究不同类型的嵌入如何对购买行为的多样性（买家通常购买的非法商品的范围）产生不对称的影响。这项研究考虑了网络嵌入如何通过将买家推荐给新供应商或“锁定”买家进行相同产品的经常性交易，对在线药品市场的药品购买多样性产生积极或消极的影响。我们分析了一个在线非法毒品市场上 7205 名参与者之间的 16,847 次非法毒品交易的新颖网络数据。与假设的网络不对称性一致，当交易是间接网络推荐的一部分时，购买者更有可能购买新型药物。尽管交换历史增加了药品购买的总体频率，但它们与新药品类型购买的减少有关。总的来说，这些流程要么有助于形成一个一体化市场，即买家从多个供应商处购买多种药物（在推荐的情况下），要么形成一个分散的市场，其特征是同一供应商对相同物质进行经常性贸易（在重复交易的情况下） ）。我们讨论了这些发现对嵌入性、非法市场、风险交易和毒品政策研究的影响。