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CHAPTER 5
CONCLUSION
This paper provides empirical results on how weather variable affects the
Thailand SET Index and the SET50 index prediction using simulated variables of
temperature, precipitation, and wind speed for one-period ahead prediction.
The results from the GARCH (1,1) model reveal the impact weather
variables on the returns of the SET index in 2006, 2007, 2010, and 2018. The weather
variables affected the volatility of the SET index in 2006, 2009, 2014, 2016, and 2018.
The out-of-sample tests showed that weather variables were unable to improve the one
period ahead predictability. It is worth noting that in 2010, the weather variable raised
the RMSE as it was added to the model.
For the SET50 index, the results showed that weather variables are
significant in 2006, 2007, and 2018. The weather variables were able to influence the
volatility. However, the RMSE value has declined over some years, but it has also
increased in some years as weather variables are added to the model. As the results, two
tests confirmed that the weather variables were unable to support prediction because
the RMSE result was significantly smaller in the common model.
Based on this study, we can conclude that the weather information cannot
play a role in forecasting investor mood which is contradict to the works of Saunder
(1993), Cao and Wei(2005), and Hirshleifer and Shumway(2003). One explanation is
that these works are related to the stock markets located in areas with extreme climates.
Due to the extreme weather, shorter periods of sunlight have become an important
factor influencing people's moods (Keller, 2005) by changing serotonin in the blood
(Denissen, 2008).The main results of this paper is aligned with the paper of
Khanthavit(2017) which find out that the weather is not the main driver of investor
mood. The output that they obtain from the paper confirms that the weather only affects
certain years and does not repeat itself every year. It supports the fact that weather is
not the primary factor in regulating investor mood (David and Tyler, 2003). Not only
the sunshine hours that can control the mood of investors but also fundamental factors
such as of dividend yields, short interest rates also play a key role in predicting returns
(Paye, 2005), which is the sunshine during the darkest hour for investment prediction.
Ref. code: 25626102042238OMU