vania-janet/multiturn-rag-retrieval-data huggingface dataset:
"ETF Creation and Redemption Process notes the process: While ETF trading occurs on an exchange like stocks, the process by   which their shares are created is significantly different. Unless a   company decides to issue more shares, the supply of shares of an   individual stock trading in the marketplace is finite. When demand   increases for shares of an ETF, however, Authorized Participants (APs)   have the ability to create additional shares on demand. Through an ""in kind"" transfer mechanism, APs create ETF units in the   primary market by delivering a basket of securities to the fund equal   to the current holdings of the ETF. In return, they receive a large   block of ETF shares (typically 50,000), which are then available for   trading in the secondary market. This ETF creation and redemption   process helps keep ETF supply and demand in continual balance and   provides a ""hidden"" layer of liquidity not evident by looking at   trading volumes alone. This process also works in reverse. If an investor wants to sell a   large block of shares of an ETF, even if there seems to be limited   liquidity in the secondary market, APs can readily redeem a block of   ETF shares by gathering enough shares of the ETF to form a creation   unit and then exchanging the creation unit for the underlying   securities. Thus, the in-kind swap to the underlying securities is only done by APs so the outflow would be these individuals taking a large block of the ETF and swapping it for the underlying securities.  The APs would be taking advantage of the difference between what the ETF's trading value and the value of the underlying securities."
The opening price is derived from new information received. It reflects the current state of the market. Opening Price Deviation (from Investopedia): Investor expectation can be changed by corporate announcements or   other events that make the news. Corporations typically make   news-worthy announcements that may have an effect on the stock price   after the market closes. Large-scale natural disasters or man-made   disasters such as wars or terrorist attacks that take place in the   afterhours may have similar effects on stock prices. When this   happens, some investors may attempt to either buy or sell securities   during the afterhours. Not all orders are executed during after-hours trading. The lack of   liquidity and the resulting wide spreads make market orders   unattractive to traders in after-hours trading. This results in a   large amount of limit or stop orders being placed at a price that is   different from the prior day’s closing price. Consequently, when the   market opens the next day, a substantial disparity in supply and   demand causes the open to veer away from the prior day’s close in the   direction that corresponds to the effect of the announcement, news or   event.
The strategy could conceivably work if you had sufficient quantity of shares to fill all of the outstanding buy orders and fill your lower buy orders.  But in this case you are forcing the market down by selling and reinforcing the notion that there is a sell off by filling ever lower buy orders.  There is the potential to trigger some stop loss orders if you can pressure it low enough.  There is a lot of risk here that someone sees what you are doing and decides to jump in and buy forcing the price back up.  Could this work sure.  But it is very risky and if you fail to create the panic selling then you risk losing big.  I also suspect that this would violate SEC Rules and several laws.  And if the price drops too far then trading on the stock would be halted and is likely to return at the appropriate price. Bottom line I can not see a scenario where you do not trigger the stop, net a profit and end up with as many or more stock that you had in the first place.
"Really arbitrage means that, currency risk aside, it shouldn't matter which exchange you buy on in price terms alone. Arbitrage will always make sure that the prices are equivalent otherwise high frequency traders can make free money off the difference. In practical terms liquidity and brokerage costs usually make trading on the ""home"" exchange more worthwhile as any limit orders etc will be filled at a better price as you will more easily find a counterparty to your trade. Obviously that will only be an issue where your quantity is significant enough to move the market on a given exchange. The volume needed to move a market is dependent upon the liquidity of the particular stock."
Chinese suppliers can quote their price in CNY rather than USD (as has been typical), and thus avoid the exchange risk from US dollar volatility- the CNY has been generally appreciating so committing to receive payments in US dollars when their costs are in CNY means they are typically on the losing end of the equation and they have to pad their prices a bit.  Canadian importers will have to buy RMB (typically with CAD) to pay for their orders and Canadian exporters can take payment in RMB if they wish, or set prices in CAD. By avoiding the US dollar middleman the transactions are made less risky and incur less costs. Japan did this many decades ago (they, too, used to price their products in USD).  This is important in transactions of large amounts, not so much for the tiny amounts associated with tourism. Two-way annual trade between China and Canada is in excess of $70bn.  Of course Forex trading may greatly exceed the actual amounts required for trade- the world Forex market is at least an order of magnitude greater than size of real international trade. All that trading in currency and financial instruments means more jobs on Bay Street and more money flowing into a very vital part of the Canadian economy.  Recent article from the (liberal) Toronto Star here.
Electronic trading is many orders of magnitude cheaper and more liquid than floor trading and is rapidly displacing it. Stil, electronic trading accounts for 79% of stock trading volume in the U.S. Polcari is losing the battle. Floor trading is still offered, but it's only used for bulk orders, so electronic trading is servicing small trades at minimum prices while floor trading is now the concierge service.
Some liquidity Since you're using IB, and you seem to be an investor not a trader, so you won't notice especially if you walk your orders, but you will suffer the bid/ask spread as everyone else albeit wider.   If buying, the best strategy unless if one is time constrained is to walk the entire bid from the best bid to the best ask.  It is highly likely that someone will hit your order before you hit the best ask.  If they don't, as a long term investor, the few pennies won't make or break you, especially if the price per share is 100 USD equivalent, but it is an excellent habit to form and fun. Since you're buying ETFs, even though your orders are small, you would be adding liquidity to your market, helping it become more efficient because your orders could be used to arbitrage against all of the ETF's holdings, in turn providing liquidity for those holdings. No liquidity This could only be done with an extremely low cost broker like IB because the trading commissions would make it prohibitively expensive. There are huge risks when trading an illiquid security such as VEUR.  EWL would be much less risky thus less expensive. Securities with no liquidity can be traded, but they must be traded very carefully.  In the case of a security that can only attract about 20 shares per day in volume, only single shares should be bid.  The market makers, suffering from a dearth in volume may not even be willing to haggle; therefore, the only recourse is a statistical arbitrageur, who will attempt to profit from the spread between other more liquid versions of the security. Considering the available alternative, VEUR is not recommended to trade.
You can get direct market access (DMA) but you have to pay for data, as this is part of the exchanges data plan, and there are plenty of other fees that are passed straight down to you. Your clearing firm also has fees that are passed on to you. In general you are looking at $150 a month on the low side, in data and software fees. If you wanted pure access, NASDAQ alone charges $6,000 a month last I checked. The different routes data routes to the exchange all have different rules, and they give you rebates for some kinds of orders in some conditions.  Brokers nowadays usually assume this responsibility (including collecting the rebates lol), at the very least, and charge an average price for routing your orders, a price that fits into their business plan and their target audience. Hope that helps.
The Key aspect is the risk of market orders;   You should be worried about point 2 & 3 when you are doing market orders.
"As you know, the market is in turmoil today. At this moment, 11:45 am, the S&P is down 2.3%, 45 points. But, premarket, it was down 100 points.  Now, premarket, I heard Jim Cramer say, ""today is not the day to use market orders."" Yes, on Mad Money, he seems a bit eccentric, but he does offer some wise advice at times.  In my opinion, your stock had some people that did just that. A market order. And, regardless of the fundamentals of this company, buyers had no orders to buy. Except a couple wise guys (in both senses) that put in buys at crazy prices. And they filled. With an Apple, trading around $100, the book probably has millions of shares on order with a buy at $80 or higher. Just an example. I'd bet there were a number of stocks that had the profile of yours, i.e. a chart reflecting trades similar to a flash crash. There are some traders smiling ear to ear, and some crying in their beer.     (Note - I use the phrase ""in my opinion."" This is the only explanation I can imagine. Occam's Razor.)"
Edit Also quite succinct and worth having a look at: http://www.interactivebrokers.com/en/trading/orders/trailingLimitTouched.php Guesswork, highly subjective As for why this might be good, well, you have to believe in momentum strategies, i.e. a market that goes down, will continue to go down, if you believe that and you believe in mean reversion as well, then a trailing limit order can assist you in not buying/selling impulsively, but closer to the mean. I've never used it that way though. What I have done, even just now to get the explanation right, is to place trailing buy and sell orders simultaneously. You will find that you can just go in with coarse estimates and because the adjustments will go towards each other, you will end up with a narrowing band of trigger prices (as opposed to trailing stop orders which will give you a widening band of trigger prices). If you believe in overshooting and equilibria then this can be one easy way to profit from it. I've just sold EURUSD for 1.26420 and bought it back at 1.26380 with a trailing amount of 5pips and a limit offset of 2pips within the time of writing this.
"What if everyone decided to sell all the shares at a given moment, let's say when the stock is trading at $40? It would fall to the lowest bid price, which could be $0.01 if someone had that bid in place. Here is an example which I happened to find online: Notice there are orders to buy at half the market price and lower... probably all the way down to pennies. If there were enough selling activity to fill all of those bids you see, then the market price would be the lowest bid on the screen. Alternatively, the bid orders could be pulled (cancelled), which would also let the price free-fall to the lowest bid even if there were few actual sellers. Bid-stuffing is what HFT (high frequency trading) algorithms sometimes do, which some say caused the Flash Crash of May 2010. The computers ""stuff"" bids into the order book, making it look like there is demand in order to trigger a market reaction, then they pull the bids to make the market fall. This sort of thing happens all the time and Nanex documents it http://www.nanex.net/FlashCrash/OngoingResearch.html Quote stuffing defined: http://www.investopedia.com/terms/q/quote-stuffing.asp I remember the day of the Flash Crash very well. I found this video on youtube of CNBC at that time. Watch from the 5:00 min mark on the video as Jim Crammer talks about PG easily not being worth the price of the market at that time. He said ""Who cares?"", ""Its not a real price"", ""$49.25 bid for 50,000 shares if I were at my hedge fund."" http://www.youtube.com/watch?v=86g4_w4j3jU You can value a stock how you want, but its only actually worth what someone will give you for it.
Note that the pros pay for extremely fast access and are literally fighting over nanoseconds to get every possible advantage. Your system won't come close to that by several orders of magnitude. Consider the implications for the kinds of automated trading you want to perform. (Pico was overstating it. Nano, at the processor level and in terms of which transaction is first into the buffers, is certainly true. A millisecond is a Long Time in this domain.)
Retail brokers and are generally not members of exchanges and would generally not be members of exchanges unless they are directly routing orders to those exchanges. Most retail brokers charging $7 are considered discount brokers and such brokers route order to Market Makers (who are members of the exchanges). All brokers and market makers must be members of FINRA and must pay FINRA registration and licensing fees.  Discount brokers also have operational costs which include the cost of their facilities, technology, clearing fees, regulation and human capital. Market makers will have the same costs but the cost of technology is probably much higher. Discount brokers will also have market data fees which they will have to pay to the exchanges for the right to show customer real time quotes.  Some of their fees can be offset through payment for order flow (POF) where market makers pay routing brokers a small fee for sending orders to them for execution. The practice of POF has actually allowed retail brokers to keep their costs lower but to to shrinking margins and spread market makers POF has significantly declined over the years.  Markets makers generally do not pass along Exchange access fees which are capped at $.003 (not .0035) to routing brokers.  Also note that The SEC and FINRA charges transactions fees. SEC fee for sales are generally passed along to customers and noted on trade confirms. FINRA TAF is born by the market makers and often subtracted from POF paid to routing firms. Other (full service brokers) charging higher commissions are charging for the added value of their brokers providing advice and expertise in helping investors with investment strategies. They will generally also have the same fees associated with membership of all the exchanges as they are also market makers subject to some of the list of cost mentioned above.  One point of note is that Market Making technology is quite sophisticates and very expensive.  It has driven most of wholesale market makers of the 90s into consolidation.    Retail routing firm's save a significant amount of money for not having to operate such a system (as well as worry about the regulatory headaches associated with running such a system).  This allows them to provide much lower commissions that the (full service) or bulge bracket brokers.
If Alice is sending only bona fide orders (that is, only placing an order at time T if, given all the information she has at time T, she truly wants and intends for it to be filled) then her cancellation at a later time actually adds to the effectiveness of and public perception of the market as a tool for price discovery (which is its ultimate purpose). [In the following example imagine that there are no such things as trading fees or commissions or taxes.] Let's say Alice offers to buy AAPL at $99.99 when the rest of the market is trading it for $100.00. By doing so she is casting her vote that the ""fair value"" of a share of AAPL is between $99.99 and $100.00. After all, if she thought the fair value of a share of AAPL was higher -- say, between $100.00 and $100.01 -- then she should be willing to pay $100.00 (because that's below fair value) and she should expect that other people in the market will not soon decide to sell to her at $99.99. If some time later Alice does decide that the fair value of AAPL is between $100.00 and $100.01 then she should definitely cancel her order at $99.99, for exactly the reason discussed above. She probably won't get filled at $99.99, and by sitting there stubbornly she's missing out (potentially forever) on the possibility to make a profit. Through the simple act of cancelling her $99.99 order, Alice is once again casting a vote that she no longer thinks that's AAPL's fair value. She is (very slightly) altering the collective opinion of the entire market as to what a share of AAPL is worth. And if her cancellation then frees her up to place another order closer to her perceived fair value (say, at $100.00), then that's another vote for her honest optinion about AAPL's price.
"Liquidity is highly correlated to efficiency primarily because if an asset's price is not sampled during the time of a trade, it's price is unknown therefore inefficient. Past prices can be referenced, but they are not the price of the present. Prices of substitutes are even worse. SPY is extremely efficient for an equity. If permitted, it could easily trade with much lower ticks and still have potential for a locked market. Ideal exchange An ideal exchange has no public restrictions on trade. This is not to say that private restrictions would need to be put in place for various reasons, but one would only do that if it were responsible for its own survival instead of being too big to fail. In this market, trades would be approximately continuous for the largest securities and almost always locked because of continuous exchange fee competition with ever dropping minimum ticks. A market that can provide continuous locked orders with infinite precision is perfectly efficient from the point of view of the investor because the value of one's holdings are always known. EMH In terms of the theory the Efficient Market Hypothesis this is irrelevant to the rational investor. The rational investor will invest in the market at large of a given asset class, only increasing risk as wealth increases thus moving to more volatile asset classes when the volatility can be absorbed by excess wealth. Here, liquidity is also helpful, the ""two heads are better than one"" way of thinking. The more invested in an asset class, the lower the class's variance and vice versa. Bonds, the least variant, dwarf equities which dwarf options, all in order of the least variance. Believe it or not, there was a day when bonds were almost as risky as equities. For those concerned with EMH, liquidity is also believed to increase efficiency in some forms because liquidity is proportional to the number of individuals invested thus reducing the likelihood of an insufficient number of participants. External inefficiency In the case of ETFs that do not perfectly track their underlying index less costs at all times between index changes, this is because they are forbidden from directly trading in the market on their own behalf. If they were allowed and honest, the price would always be perfect and much more liquid than it otherwise should be since the combined frequency of all index members is much higher than any one alone.
"Before the prevalence of electronic trading, trading stocks was very costly, dropping from ~15c in the late 1970s to less than a nickel per share today.  Exchange fees for liquidity takers are ~0.3c per share, currently. When orders were negotiated exclusively by humans, stocks used to be quoted in fractions rather than decimal, such as $50 1/2 instead of something more precise like $50.02. That necessary ease of negotiation for humans to rapidly trade extended to trade size as well.  Traders preferred to handle orders in ""round lots"", 100 shares, for ease of calculation of the total cost of the trade, so 100 shares at $50 1/2 would have a total cost of $5,050.  The time for a human to calculate an ""odd lot"" of 72 shares at $50.02 would take much longer so would cost more per share, and these costs were passed on to the client. These issues have been negated by electronic trading and simply no longer exist except for obsolete brokerages.  There are cost advantages for extremely large trades, well above 100 shares per trade. Brokerage fees today run the gamut: they can be as insignificant as what Interactive Brokers charges to as high as a full service broker that could charge hundreds of USD for a few thousand USD trade.  With full service brokerages, the charges are frequently mystifying and quoted at the time a trade is requested.  With discount brokerages, there is usually a fee per trade and a fee per share or contract.  Interactive Brokers will charge a fee per share or option only and will even refund parts of the liquidity rebates exchanges provide, as close as possible to having a seat on an exchange.  Even if a trader does not meet Interactive Brokers' minimum trading requirement, the monthly fee is so low that it is possible that a buy and hold investor could benefit from the de minimis trade fees. It should be noted that liquidity providing hidden orders are typically not rebated but are at least discounted. The core costs of all trades are the exchange fees which are per share or contract.  Over the long run, costs charged by brokers will be in excess of charges by exchanges, and Interactive Brokers' fee schedule shows that it can be reduced to a simple markup over exchange fees.   Exchanges sometimes have a fee schedule with lower charges for larger trades, but these are out of reach of the average individual."
Unless you want to be a short term day trader, then it is not foolish to be an end of day trader. If you are looking to be a medium to long term trader/investor then it is quite acceptable to put orders in after market close. Some would say it is even less risky, because you are not watching the price fluctuate up and down and letting your emotions getting the best of you.
Dollar cost averaging is beneficial if you don't have the money to make large investments but are able to add to your holding over time. If you can buy the same monetary amount at regular intervals over time, your average cost per share will be lower than the stock's average value over that time. This won't necessarily get you the best price, but it will get you, on the whole, a good price and will enable you to increase your holdings over time. If you're doing frequent trading on a highly volatile stock, you don't want to use this method. A better strategy is to buy the dips: Know the range, and place limit orders toward the bottom of the range. Then place limit orders to sell toward the high end of the range. If you do it right, you might be able to build up enough money to buy and sell increasing numbers of shares over time. But like any frequent trader, you'll have to deal with transaction fees; you'll need to be sure the fees don't eat all your profit.
And just as easily, someone could find a reason for such a derivative to exist.  Let's say I'm a vendor of memorabilia for a given sports team, but unlike most vendors I'm only a vendor for a particular team.  Given that there is a large lead time between orders placed and memorabilia received (perhaps on the order of a month between order and receipt), it is inherently risky to order large orders towards the end of a season.  However, if they're going to be in the playoffs, there's a huge opportunity to sell, but if they don't, you'd be left with tons of surplus inventory.  So, wouldn't it be handy for there to be a way to hedge that risk?    We've actually seen times when such things aren't unreasonable.  Large risks are [hedged away](http://online.wsj.com/article/SB10001424052702303877604577380593015786140.html), even in sports.