آیا ما با چیزی که به شخصی می گوییم،تاثیرگذار هستیم و چه زمانی؟ بررسی تاثیر فعالیت و ارتباطات در پاسخ  میکروبلاگ ها به محصولات جدید  Does who we are affect what we say and when? Investigating the impact of activity and connectivity on  microbloggers’ response to new products

1. Introduction Consumers have embraced social media, generating massive amounts of online content about products that interest them (Brown, Broderick, & Lee, 2007). Marketers use this information, called electronic word-of-mouth (eWOM), to track their brands and gain insights into consumer behavior (You, Vadakkepatt, & Joshi, 2015). They are particularly interested in the evolution of sentiments contained in eWOM because its pattern tends to be correlated with brand awareness (Liu, 2006), sales (Srinivasan, Rutz, & Pauwels, 2015), and future online activity (Moe & Schweidel, 2012). Because of its low cost and high volume, eWOM is useful for gauging early consumer response to new products (Hennig-Thurau, Wiertz, & Feldhaus, 2015). Furthermore, because its content is visible to and searchable by others, eWOM influences future online purchases. Therefore, despite having little control over eWOM (Godes et al., 2005), marketers prefer online conversations about their new products to be positive or neutral. However, eWOM related to new products contains a variety of sentiments (Srinivasan et al., 2015) because of variations in product evaluations and heterogeneity in posters’ characteristics. This paper focuses on the heterogeneity among posters and addresses the following research question: Does past online activity and the structure of online social networks influence the timing and valence of eWOM following the launch of a new product? Although eWOM takes many forms, this research focuses on microblogs, which are short, instantaneous, non-interactive, non-invasive, searchable posts. Almost one in five such posts mentions a brand (Jansen, Zhang, Sobel, & Chowdury, 2009), because of which microblogs are an influential form of eWOM that marketers are increasingly using to gain insights into consumers and stimulate new product adoption (HennigThurau et al., 2015).