Relation between Indian and other mkts.

Hi Friends,

I am new to the markets and am trying to feel my way around.
My question is :
What is the relation between Indian market and the
other markets esp. China and US. ?
Everytime the US market goes down the Indian market also falls. However
each time the Indian market comes down there may not be a similar impact on the US market.

What is going on ? Are the Indian markets not based on fundamentals. Or is the index actually overvalued at current rates.
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