E-commerce platforms support the needs and livelihoods of their two most important stakeholders -- customers and producers/sellers. Multiple algorithmic systems, like ``search'' systems mediate the interactions between these stakeholders by connecting customers to producers with relevant items. Search results include (i) private label (PL) products that are manufactured/sold by the platform itself, as well as (ii) third-party products on advertised / sponsored and organic positions. In this paper, we systematically quantify the extent of PL product promotion on e-commerce search results for the two largest e-commerce platforms operating in India -- Amazon.in and Flipkart. By analyzing snapshots of search results across the two platforms, we discover high PL promotion on the initial result pages (~ 15% PLs are advertised on the first SERP of Amazon). Both platforms use different strategies to promote their PL products, such as placing more PLs on the advertised positions -- while Amazon places them on the first, middle, and last rows of the search results, Flipkart places them on the first two positions and the (entire) last column of the search results. We discover that these product placement strategies of both platforms conform with existing user attention strategies proposed in the literature. Finally, to supplement the findings from the collected data, we conduct a survey among 68 participants on Amazon Mechanical Turk. The click pattern from our survey shows that users strongly prefer to click on products placed at positions that correspond to the PL products on the search results of Amazon, but not so strongly on Flipkart. The click-through rate follows previously proposed theoretically grounded user attention distribution patterns in a two-dimensional layout.

翻译：电商平台支撑着其两大关键利益相关方——消费者与生产商/销售商——的需求与生计。以“搜索”系统为代表的多重算法系统通过将消费者与提供相关商品的生产商相连接，协调着这些利益相关方之间的互动。搜索结果既包含(i)由平台自主生产/销售的自有品牌产品，也包含(ii)位于广告/赞助位及自然位的第三方产品。本文针对印度两大头部电商平台——Amazon.in与Flipkart——系统性地量化了其电商搜索结果中自有品牌产品的推广程度。通过对两大平台搜索结果快照的分析，我们发现初始结果页存在高强度的自有品牌推广（Amazon首屏搜索结果页中约15%的自有品牌产品位于广告位）。两家平台采用不同策略推广自有品牌产品，例如在广告位投放更多自有品牌——Amazon将其置于搜索结果的首行、中间行与末行，而Flipkart则将其置于搜索结果前两位及（整列）末列位置。我们发现两家平台的产品布局策略均符合文献中已有的用户注意力引导策略。最后，为补充采集数据的发现，我们在Amazon Mechanical Turk上对68名参与者开展了问卷调查。调查点击模式显示：用户强烈倾向于点击Amazon搜索结果中与自有品牌产品对应的位置，而Flipkart上的这种倾向则较弱。其点击率分布符合先前研究中提出的二维布局下基于理论推演的用户注意力分布模式。