在双边AdTech市场中扩展可靠实验：ZMS预算拆分

Retail media has transformed e-commerce by allowing brands to advertise their products directly to consumers right at the digital point of sale. However, in a complex advertising marketplace, testing a new feature requires more than a conventional user-level A/B test.

零售媒体通过允许品牌直接在数字销售点向消费者投放广告产品，彻底改变了电子商务。然而，在复杂的广告市场中，测试新功能需要的不仅仅是传统的用户级 A/B 测试。

Most A/B tests rest on a simple assumption: what User A does doesn't affect User B. In a standard consumer app, that's mostly true: you randomize users, show them different variants, and compare the results.

大多数 A/B 测试基于一个简单的假设：用户A的行为不会影响用户B。在标准的消费者应用中，这基本是正确的：你对用户进行随机分组，向他们展示不同的变体，然后比较结果。

Retail media, however, operates slightly differently. It's a two-sided marketplace where advertisers compete for visibility via ad placements, customers see the results, and the whole system runs on a finite resource: advertisers' budgets. When experiment variants draw from the same campaign budgets, the statistical validity of the test is compromised. The control and treatment groups lose their independence, entering a cycle where they actively engage in Cannibalization Bias against one another.

然而，零售媒体的运作方式略有不同。它是一个双边市场，广告商通过广告位竞争曝光率，客户看到结果，而整个系统运行在一个有限的资源上：广告商的预算。当实验变体从相同的广告系列预算中提取资源时，测试的统计有效性就会受到损害。对照组和实验组失去了独立性，进入了一个相互积极进行 Cannibalization Bias 的循环。

In this blog post, we describe how we used Budget Split and Orthogonal Concurrency to address this challenge within our experimentation framework, and how these capabilities improved our testing between 2023 and 2025.

在这篇博客文章中，我们描述了如何在实验框架中使用 Budget Split 和 Orthogonal Concurrency 来应对这一挑战，以及这些功能如何改善了我们在2023年至2025年间的测试。

SUTVA Violations and Budget Cannibalization

SUTVA违背与预算蚕食

In a standard A/B test, the validity of your results depends on the Stable Unit Treatment Value Assumption (SUTVA). The core pillar of SUTVA is no interference between the variants of the experiment, meaning the treatment assigned to one user should not affect the outcome for another user. In an advertising marketplace, this assumption is easily violated.

在标准的A/B测试中，结果的...