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臺大管理論叢
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28
卷第
1
期
analyzed the information content of media reports using linguistic analysis and found that
the information content of such reports can affect the stock market through the sentiment
and behavior of investors. Within these studies, it is generally argued that sentiment
relating to news reports can be adopted by investors as a factor leading to expectations of
abnormal returns.
9
Furthermore as demonstrated by Tetlock (2007) and Tetlock, Saar-Tsechansky, and
Macskassy (2008), the number of words relating to investor sentiment in firm-specific
news reports may provide an effective forecast of the earnings of a firm, which suggests
that media reports are capable of capturing firm fundamentals under different aspects that
are not easily quantified, or indeed, that may contribute to stock price efficiency. Jang,
Yang, and Chen (2014) also found that media coverage and tenor could promote a good
image for firms which would be of direct benefit to their future performance.
Nevertheless, the potential does exist for media coverage to be manipulated; for
example, Kothari et al. (2009) noted that firms could manipulate the timing of news
release, whilst Solomon (2012) pointed out that firms could spin their news, effectively
generating more (less) media coverage of positive (negative) press release. Since
corporate reputation is an intangible asset which cannot be measured with any great
certainty, we apply content analysis to construct the measures of media coverage and the
sentiment ratio as proxies for ‘media reputation’.
Zyglidopoulos, Georgiadis, Carroll, and Siegel (2012) argued that firms may enhance
their CSR level to gain higher media coverage; we similarly propose that firms engaging
in CSR may have a higher media reputation, whilst also focusing on the variations in
media reputation between CSR winners and non-CSR firms during CSR award
announcement periods in order to observe whether firms tend to manipulate their media
reputation. This leads to the formulation of Hypothesis 3:
Hypothesis 3: The media reputation of CSR winners will be higher than that of non-
CSR firms during periods of CSR awards announcements.
It has been shown that media reports can have direct impacts on the stock market
trading behavior of investors. Some of the more recent studies suggest that media reports
can reduce information asymmetry for stakeholders and establish the reputation of the
9 See Tetlock (2007), Tetlock et al. (2008), and Lu and Wei (2013, 2014).