Municipal bonds exhibit considerable retail pricing variation, even for same-size trades of the same bond on the same day, and even from the same dealer. Markups vary widely across dealers. Trading strongly clusters on eighth price increments, and clustered trades exhibit higher markups. Yields are often lowered to just above salient numbers. Machine learning estimates exploiting the richness of the data show that dealers that use strategic pricing have systematically higher markups. Recent Municipal Securities Rulemaking Board rules have had only a limited impact on markups. While a subset of dealers focus on best execution, many dealers appear focused on opportunistic pricing.

中文翻译：

---

市政债券交易商是否为客户提供“公平合理”的定价？

市政债券显示出相当大的零售定价差异，即使对于同一天同一债券的相同规模交易，甚至来自同一交易商。不同经销商的加价差异很大。交易强烈聚集在第八个价格增量上，并且聚集的交易表现出更高的加价。产量通常会降低到略高于显着数字。利用丰富数据的机器学习估计表明，使用战略定价的经销商有系统地更高的加价。最近的市政证券规则制定委员会规则对加价的影响有限。虽然一部分经销商专注于最佳执行，但许多经销商似乎专注于机会主义定价。