[目的/意义]突发事件情境下，信息搜寻阻碍和信息不对称导致应急信息传播受阻。对突发事件情境下网络舆情信息摩擦评估与分析，进而为突发事件应急管理提供可参考的理论工具，对政府舆情治理能力提升具有重要意义。[方法/过程]基于信息经济学中的信息摩擦概念，从信息搜寻阻碍和信息不对称两个维度构建突发事件情境下网络舆情信息摩擦评估指标体系，利用熵权法对不同主题时段的信息摩擦进行评估和排序。基于Krus⁃kal-Wallis非参数检验对不同生命周期和主题类型的网络舆情信息摩擦进行比较分析。基于公众角度对应急处置效果进行测度，通过相关性分析、构建应急处置效果预测模型和SHAP模型探究信息摩擦对应急处置效果的影响机制。[结果/结论]研究建立了网络舆情信息摩擦的量化标准，分析发现不同生命周期和主题类型信息摩擦存在显著差异，起始期和爆发期信息摩擦较高，调查问责类和情绪表达类主题信息摩擦较高。信息摩擦与应急处置效果之间存在显著负相关关系，信息搜寻阻碍相较于信息不对称对应急处置效果的影响更大。

[Purpose/significance] In emergency situations, information search obstacles and information asymmetry lead to the obstruction of event information dissemination. Evaluating and analyzing the friction of online public opin⁃ion information in emergency situations, and providing reference theoretical tools for emergency management are of great significance for improving the government's public opinion governance capabilities. [Method/process] Based on the concept of information friction in information economics, an evaluation indicator system for online public opinion in⁃formation friction in the context of public events is constructed from two dimensions: information search obstacles and information asymmetry. Using the entropy weight method to evaluate and rank information friction in different thematic time periods, we compare online public opinion information friction based on the Kruskal Wallis non parametric test for different lifecycles and topic types. The effectiveness of emergency response is measured from a public perspective.The impact mechanism of information friction on emergency response effectiveness is revealed through correlation anal⁃
ysis. [Result/conclusion] This study establishes a quantitative standard for the friction of online public opinion infor⁃mation. Results find significant differences in information friction among different lifecycles and theme types, with high⁃er friction in the initiation and outbreak periods, and higher friction in the topics of investigation accountability and emotional expression. There is a significant negative correlation between information friction and the effectiveness of emergency response. Information search obstacles have a greater impact on the effectiveness of emergency response compared with information asymmetry. The findings provide suggestions for government departments to govern the dis⁃semination of online public opinion information during public events.