Abstract:     A brand community is an online community led by a company, which can effectively promote information exchange and interaction among community members, and is of great significance to user innovation. However, users′ characteristics are very different, and their impacts on innovative behaviors are not the same, bringing both opportunities and challenges to brand communities. Therefore, if companies want to effectively promote user innovation, it is very important to study the generating mechanism of user innovation behavior in brand communities.Many scholars have explored many driving factors of innovative behavior, mainly focusing on environmental and personal factors. However, few studies have explored user sense of power from the perspective of subjective psychological characteristics and its boundary conditions. In fact, individuals with high sense of power have high cognitive flexibility and freedom of behavior, which are highly adapted to innovative behavior′s challenging and adventurous characteristics, showing that sense of power may also affect innovative behavior. Previous studies mainly focus on sense of power′s influence on consumption behavior (consumer′s in-role behavior), while ignoring the innovative behavior (consumer′s extra-role behavior). Since brand communities have become an important platform for corporate innovation, studying the relationship between user′ sense of power and innovative behavior in the community has become particularly important, but related research is extremely scarce.This study builds an influence mechanism model to illustrate user′s sense of power′s impacts on innovative behavior in brand communities. Based on proactive motivation model, self-efficacy, community identification and harmonious passion are introduced as mediators between sense of power and user innovative behavior in brand communities. Moreover, according to situated focus theory of power, this study proposes perception of community support as the important boundary condition.This study selects user members from Xiaomi community to conduct surveys. This community has more than 10 million registered and active users, who are external knowledge contributors to enterprise product innovation and suitable for survey. A total of 371 valid questionnaires were collected through forum messages and QQ groups.Based on the empirical research, the following conclusions can be drawn: (1) user′s sense of power has a significant positive effect on innovative behavior. This conclusion further introduces sense of power from psychology to marketing, and brings sense of power′s effects from in-role consumption behaviors to extra-role innovative behaviors. Meanwhile, this conclusion explains individuals′ innovative behavior′s influencing factors from objective personal resources to subjective sense of power. (2) Self-efficacy, community identification and harmonious passion play as a partial mediator between sense of power and innovative behavior. This study uses proactive motivation model to explore the mediating effect between power and innovation, which establishes a strong connection between proactive characteristics of users and sense of power. In addition, proactive motivation model has been used to explain employee behavior in the field of organizational behavior, while this study uses proactive motivation model to explain user innovation behavior in the field of consumer behavior, expanding its research boundaries. (3) Perceived community support positively moderates the relationship between users′ sense of power and self-efficacy, community identification, and harmonious passion. Different from previous scenarios mainly focusing on traditional environment, this article explores the moderating effect of perceived community support in brand communities on Internet. The introduction of perceived community support as community context echoes situated focus theory of power, and also expands the theory.This research provides practical suggestions for companies to manage brand communities and stimulate user innovation. First, companies can take measures to stimulate more self-efficacy, community identification and harmonious passion of users with a high sense of power. Second, when companies build and operate brand communities, they should not only pay attention to the basic functions of brand community, but also encourage users to share their daily life to strengthen emotional connection between users and enhance community support perception.

Key words:  sense of power, user innovative behavior, self-efficacy, community identification, harmonious passion, perceived community support