The article seems somewhat on the fluff-and-feathers side. It doesn't really explain anything. The only non-obvious thing it says is:
> Robinhood receives a fixed rate per spread (vs. a fixed rate per share by the other eBrokers). Rather than receiving simple payment by volume, Robinhood receives a percentage of the spread between the bid and the ask in each trade. This is interesting because while HFT proponents insist their practices narrow spreads, some critics maintain that high-frequency trading ends up widening spreads.
Unfortunately, what this excerpt claims as "interesting" makes no logical sense. The fact that RH is paid by HFT on the spread would suggest that HFT like to get order flow in stocks that already have a large spread. It is completely unclear how this is related to the claim that HFT tend to increase the spread.
The "traditional" interpretation is that HFT make money from creating liquidity. This means they take illiquid stocks (with large spread) and make them liquid (reducing the spread). Since they make money doing that, they are willing to pay for orders in illiquid stocks.
Is this the correct interpretation? I have no clue. But it seems the article's author has even less clue, and adds nothing of value to the discussion.
> Robinhood receives a fixed rate per spread (vs. a fixed rate per share by the other eBrokers). Rather than receiving simple payment by volume, Robinhood receives a percentage of the spread between the bid and the ask in each trade. This is interesting because while HFT proponents insist their practices narrow spreads, some critics maintain that high-frequency trading ends up widening spreads.
Unfortunately, what this excerpt claims as "interesting" makes no logical sense. The fact that RH is paid by HFT on the spread would suggest that HFT like to get order flow in stocks that already have a large spread. It is completely unclear how this is related to the claim that HFT tend to increase the spread.
The "traditional" interpretation is that HFT make money from creating liquidity. This means they take illiquid stocks (with large spread) and make them liquid (reducing the spread). Since they make money doing that, they are willing to pay for orders in illiquid stocks.
Is this the correct interpretation? I have no clue. But it seems the article's author has even less clue, and adds nothing of value to the discussion.