The complementary-competitive interplay of consumer information search and experience sharing: Implications for targeted advertising and firm performance

The proliferation of targeted media platforms enables firms to deliver tailored advertising to specific consumer segments, yet the heterogeneous influences of pre-purchase information search and post-purchase sharing on targeted advertising performance remain underexplored in extant research. This paper constructs a two-period symmetric duopoly game model with fully rational firms and consumers to analyze theoretical associations between two distinct consumer information behaviors and firms' equilibrium advertising and profit outcomes. We set homogeneous products, symmetric competitors, and two types of consumers (loyal buyers and comparison shoppers) to explore the strategic interplay of corporate advertising, pricing and consumer information activities. This model adopts a differentiated search cost framework: digital information access incurs zero monetary expenses, yet endogenous cognitive information overload creates non-negligible mental frictions. Search intensity s is the consumer's generic choice variable; s* denotes the endogenous equilibrium search intensity solved from consumer utility maximization (not an exogenous primitive parameter), which lies within interior range (0,1) rather than corner solution s=1. Experience‑sharing intensity e is treated as an exogenous symmetric parameter for analytical tractability. Model-derived predictions are summarized as follows: (1) Consumer information search acts as a complementary force for targeted ads by lowering information frictions, lifting conversion rates and raising equilibrium profitability within valid parameter ranges; (2)Experience sharing generates dual competitive effects: moderate peer reviews expand market awareness, while excessive price-related sharing intensifies cross-brand price rivalry and suppress firm returns; (3) The joint interaction of search and sharing shapes equilibrium advertising intensity: optimal ad spending falls as primitive cognitive‑friction parameters shift to raise endogenous equilibrium search intensity s*, and firms need context-dependent strategies to cope with consumer sharing. Theoretically, this work unifies pre-purchase search and post-purchase sharing into a single dynamic duopoly framework to fill research gaps that separate the two consumer behaviors. Practically, the model provides neutral theoretical insights; tentative suggestions for advertising‑message content represent directions for future empirical testing rather than formal model outputs. All theoretical conclusions derived in this paper hold only within the feasible interior-equilibrium parameter domain defined in Text S2.9. Numerical simulation figures serve purely as numerically illustrated examples; formal mathematical proofs are provided in the appendices. All conclusions are mathematical predictions derived under preset model assumptions, rather than empirically validated causal relationships.