Abstract: Network aggregation effect leads to frequent occurrences of “instant celebrification” and “reputation crumble” caused by the streamer. This paper studies how brand owner and streamer choose their own marketing behaviors when facing the possibility of “instant celebrification” and “reputation crumble”. Thus, we construct four decision-making scenarios: streamers may experience instant celebrification (D scenario), streamers may experience reputation crumble (C scenario), streamers may experience instant celebrification first and then reputation crumble (DC scenario), and streamers may experience reputation crumble first and then instant celebrification (CD scenario). To address these scenarios, this paper constructs the corresponding differential game models to examine the impact of potential “instant celebrification” or (and) “reputation crumble” on product marketing and live-streaming promotion efforts, and long-term profits of brand owner and streamer. The results indicate that under D (C) scenario, brand owner and streamer always make the highest (smallest) product marketing and live-streaming promotion efforts before instant celebrification (reputation crumble); Under DC (CD) scenario, a low-impact instant celebrification (reputation crumble) will prompt brand owner and streamer to reduce (increase) product marketing and live-streaming promotion efforts before instant celebrification (reputation crumble). Using scenario D(C) as a baseline, numerical simulations show that a potential “instant celebrification” (“reputation crumble”) event could damage (increase) the brand owner’s long-term profits. Compared to brand owner, the streamer’s long-term profit is more susceptible to the impact of instant celebrification and reputation crumble, meaning that when its long-term profit has already benefited (suffered) from instant celebrification (reputation crumble), the brand owner’s long-term profit may not necessarily benefit (suffer) from instant celebrification (reputation crumble).

Key words: instant celebrification, reputation crumble, product marketing effort, live-streaming promotion effort