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  界面新闻记者|肖芳

  界面新闻编辑|文姝琪

  多次因为热点事件的处理引发争议之后,抖音近日首次公开了算法原理。

  据界面新闻了解,抖音安全与信任中心网站已上线试运营,正向用户、创作者、社会各界征集意见。该网站公开了抖音算法推荐系统的原理、用户行为背后的算法推荐逻辑以及平台人工治理识别各类风险等内容。

  在此前举办的2025中国网络媒体论坛上,抖音总裁韩尚佑解释了公开算法推荐系统原理的原因。他表示,很多人对推荐算法技术存在误解,认为算法是给内容打上对应标签,再给用户打上对应的属性,最后通过数据运算,把对应标签的内容推荐给有对应属性的用户。实际上,抖音的推荐系统已几乎不依赖对内容或者用户打标签,而是通过一系列神经网络计算,直接预估每一个用户对每一个内容的目标行为,并挑选出概率最大的一部分内容,推荐给用户。

  抖音安全与信任中心网站也着重介绍了这部分内容:当用户打开抖音时,抖音的推荐算法会给候选视频打分,并把得分最高的视频推送给用户。用户在观看时可以对看到的视频做出各种互动,这些互动体现了用户对这个视频的感兴趣程度。比如,“看完了”就是一次反馈动作,“点赞”也是一次反馈动作。用户对观看的视频的每一次反馈,都会对内容流量产生影响。

  抖音算法的核心逻辑就是通过预测用户行为概率和用户不同行为的价值权重来确定视频推荐优先级。

  虽然推荐算法已并非新生事物,围绕它的争议却从未间断。这些争议包括推荐算法带来标题党、低质量、甚至虚假内容以及信息茧房的问题。但算法也有积极的一面,其提升了信息分发效率、促进信息流动,不能因为存在问题就被一棒子打死。

  今年以来,抖音和今日头条陆续释放算法和平台治理的相关信息,试图通过增加透明性来破解算法引发的种种争议。

  首次解释抖音算法不追求平台短期数据

  从抖音公开的算法原理和算法特点来看,抖音的推荐算法与国内外大部分内容推荐平台相似,包含召回、过滤、排序等环节,重点是学习用户行为。

  抖音基于用户行为的推荐方法包含多种技术模型,如协同过滤、双塔召回、Wide&Deep模型等。算法可以在完全“不理解内容”的情况下,找到兴趣相似的用户,把其他人感兴趣的内容推荐给该用户。

  其中,协同过滤推荐算法是最经典的推荐算法。简单来说,协同过滤就是协同用户的行为,一起对海量的信息进行过滤,从中更加快速筛选出用户可能会产生行为(比如完播、点赞)的内容。比如,用户A观看了内容X、Y、Z,用户B观看了内容X、Z、W,这意味着X和Z之间就有较高的相似度,系统会根据用户对已观看或已评分内容的偏好,为用户推荐与这些内容相似的其他内容。其原理就是,找到和你兴趣相似的用户,把他们感兴趣的内容也推荐给你。

  Wide&Deep模型是抖音推荐算法主力模型之一。Wide部分的主要作用是让模型具有较强的“记忆能力”,模型可直接学习并利用历史数据中物品或者特征的“共现频率”;Deep部分的主要作用是让模型具有“泛化能力”,能够发掘稀疏甚至从未出现过的稀有特征与最终标签相关性。这个模型能够解决协同过滤算法推荐结果头部效应比较明显的问题。

  算法能学习、预估用户行为,但因其无法理解内容语义,对内容的理解存在不足,可能导致违法违规、不良内容被推荐传播。因此,算法在真实使用场景中,必须由平台治理对其进行约束和规范。抖音平台治理体系包括异常感知、标准定义、机器识别、人工研判、风险处置等过程。其中,人工主要负责“深度”,确保专业、敏感或疑难等问题尽可能精准研判。

  在很多用户的认知中,算法会推荐一些博眼球甚至擦边的内容来提升用户使用时长和用户留存率。在4月15日举办的抖音开放日上,抖音方面首次对这个问题进行了解释。

  抖音算法工程师刘畅表示,抖音更关注用户长期价值,而非追求平台的短期数据。为此,抖音算法考虑了众多目标,如完播、评论、点赞、对作者长期消费、分享、跟拍等,力图计算出更符合用户长期价值的目标。

  他同时还对引发争议较多的信息茧房问题进行了回应:为引导算法打破信息茧房,抖音算法在多目标建模体系下,设置了专门的探索维度。

  一是对用户在平台上已经表现出的兴趣,尽可能推荐更多样的内容,通过多样性打散、多兴趣召回、扶持小众(长尾)兴趣等方法控制相似内容出现的频次。二是帮助用户探索更多新兴趣,采用随机探索、基于用户社交关系拓展兴趣、搜索推荐联动、“不感兴趣”不再展现等多种方式,让用户的主动行为影响推荐系统,使推荐更加个性化和多样化。

  从抖音对算法原理的一系列解释来看,其想强调的是算法的核心是以数学计算学习人类行为,它将用户对内容的具体偏好抽象为高维空间中的数学映射关系,而算法本身是没有偏好的。

  这种解释并没有错,但算法带来的争议并不是简单的数学问题,而是夹杂着诸多社会热点事件本身引发的争议以及公众情绪,这才是消除公众误解的关键和难点。

  打破算法争议,抖音仍需提升热点事件处置的透明性

  回溯去年以来抖音和今日头条算法引发的争议,每一次都和具体的热点事件相关。

  比如,在郭有才等网红走红过程中,一些网友的疑问在于,网红的走红是否由平台算法强推出来的。在一些热点新闻中,公众关心的是算法推荐是否加剧了谣言的传播、让谣言处理的难度提升。

  在和界面新闻记者谈及抖音算法引发的争议时,多位抖音用户表示,相比于算法的数学原理,他们更关心的是平台对热点事件处置的透明性。

  实际上,平台对热点事件处置的不透明加剧了公众对算法的误解。比如,在吴柳芳事件中,很多用户认为是平台通过算法推荐吴柳芳的擦边内容,带动其走红,进而质疑平台算法故意推荐擦边内容。而真实的情况是,在成为社会热点事件之前,吴柳芳在抖音上的流量和粉丝量一直较少,平台也并未对其进行推荐。其流量的增长是在该热点引发社会关注后,用户主动搜索导致的。

  去年12月以来,抖音集团副总裁李亮开始在微博上活跃,多次解释算法的相关问题,并对吴柳芳事件、抖音用户把钱读成米等热点事件进行了回应,增加与公众的沟通。

  但这还远远不够。比如在张兰封号事件中,虽然李亮在微博上解释封号的原因是当事人推荐不实信息进行商业炒作,但网友们仍然对判罚的尺度存在疑问,争议依然发酵数日。

  针对公众关心且争议比较大的问题,抖音也在抖音安全与信任中心网站上进行了解释。目前,网站解释的问题包括“抖音为何突出收藏按钮”“App会窃听用户谈话吗”“网红是平台强推出来的吗”等。据界面新闻了解,抖音后续还将在该网站解释更多争议性问题。

  一位抖音内部人士告诉界面新闻,抖音内部收集到了很多反馈信息,最终决定上线一个网站来和外界沟通,把已经做的工作向外界传递出去。

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