廣告的關鍵字效應：認知與策略

Abstract

本文研究了消費者的關鍵詞搜尋對市場結構、廠商定價與廣告策略的影響。消費者在搜尋時使用特定成分或性質作為關鍵詞的動機取決於他們接收到的廣告數量。我們考慮有關廠商產品成分或性質的完全與不完全訊息，再將模型擴展到三家廠商的案例，並討論廠商位置變化對投放廣告之動機的影響。我們的研究結果表明，當市場上有兩家廠商時，如果某一廠商是唯一一家擁有達特定標準之成分或性質的廠商，就會發布廣告，且其動機隨著市場規模和產品價值的增加而增加。其次，廠商是否了解競爭對手的產品資訊會影響其透過廣告誤導競爭對手的策略和動機，若廠商具備達特定標準之成分或性質，便會發布廣告，且廣告數量會隨著競爭對手的信念而增加。最後，我們比較完全與不完全訊息下的價格和廣告策略，並發現在不完全訊息下，廠商的價格和廣告數量都較高。

This paper examines the effects of consumers’ “keyword search” on market structures as well as firms’ pricing and advertising strategies. Consumers’ incentives to use a specific ingredient as keyword in searches depend on the amount of advertisements they receive from firms. We consider both complete and incomplete information about firms’ product ingredients. We also extend the model to three-firm cases and investigates how firm’s incentives to advertise changes with the opponents’ location. Our results first show that when there are two firms in the market, a firm will post advertisements if it is the only firm that has enough ingredients, and the incentive for advertisements to cause keyword effects is increasing with the market size and product values. Second, whether firms know competitors’ information about product ingredients will affect their strategies and motivations to mislead their competitors by advertisements. Our result shows that if firms have sufficient ingredients, they will advertise, and the levels of advertisements will increase with the opponent’s beliefs. Third, we compare the results of price and advertisement\nstrategies with complete information and incomplete information and find that both firms’ prices and the levels of advertisements are higher under incomplete information.