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system
buying an etf vs. the explicit index
user
what reason would i have in buying an etf? apart from the efforts, the real reason is the ticket size. one can't buy shares in fraction. to truly reflect the index in equal weight, the amount to invest will be in multiples of millions [depending on the index and the stock composition]   this related question should help you understand why it is difficult even for large fund house to exactly mimic the index. why do passive etfs require so much trading (and incur costs)?
assistant