Brief concept about price movement of a particular stock [duplicate]
There isn't a formula like that, there is only the greed of other market participants, and you can try to predict how greedy those participants will be. If someone decided to place a sell order of 100,000 shares at $5, then you can buy an additional 100,000 shares at $5. In reality, people can infer that they might be the only ones trying to sell 100,000 shares right then, and raise the price so that they make more money. They will raise their sell order to $5.01, $5.02 or as high as they want, until people stop trying to buy their shares. It is just a non-stop auction, just like on ebay. It depends completely on the current order book for that security.  There is literally no telling how that buy order would move the price of a stock in general. The problem with predicting with accuracy what a stock price will do in any given situation is that there are two main factors that affect a stocks price. The first factor is based somewhat in math as it takes into account numbers such as supply and demand, earnings per share, expected earnings, book value, debt ratio and a wide variety of other numbers. You can compile all those numbers into a variety of formulas and come up with a rational estimate of what the stock should sell for. This is all well and good and if the market were entirely rational it would rarely make news because it would be predictable and boring. This is where our second factor throws a wrench in the works.  The second factor affecting stock price is emotional. There are many examples of people's emotions affecting stock price but if you would like a good example look up the price fluctuations of Apple  (AAPL) after their last couple earnings reports. Numerically their company looks good, their earnings were healthy, their EPS is below average yet their price fell following the report. Why is that?  There really isn't a rational reason for it, it is driven by the emotions behind unmet expectations. In a more general sense sometimes price goes down and people get scared and sell causing further decline, sometimes people get excited and see it as opportunity to buy in and the price stabilizes. It is much more difficult to anticipate the reaction the market will have to people's emotional whims which is why predicting stock price with accuracy is near impossible.  As a thought along the same line ask yourself this question; if the stock market were entirely rational and price could be predicted with accuracy why is there such a wide range of available strike prices available in the options market?  It seems that if stock price could be predicted with anything remotely reassembling accuracy the options market need a much smaller selection of available strike prices.
News about a company is not the only thing that affects its stock's price. There is also supply and demand.  That, of course, is influenced by news, but it is not the only actor.  An insider, with a large position in their company's stock, may want to diversify his overall portfolio and thus need to sell a large amount of stock.  That may be significant enough to increase supply and likely reduce the stock's price somewhat. That brings me to another influence on stock price: perception.  Executives, and other insiders with large positions in their company's stock, have to be careful about how and when they sell some of that stock as to not worry the markets.  Many investors watch insider selling to gauge the health of the company. Which brings me to another important point.  There are many things that may be considered news which is material to a certain company and its stock.  It is not just quarterly filings, earnings reports and such.  There is also news related to competitors, news about the economy or a certain sector, news about some weather event that affects a major supplier, news about a major earthquake that will impact the economy of a nation which can then have knock-on effects to other economies, etc... There are also a lot of investors with varying needs which will influence supply and demand.  An institutional investor, needing to diversify, may reduce their position in a stock and thus increase supply enough that it impacts the stock's price.  Meanwhile, individual investors will make their transactions at varying times during the day.  In the aggregate, that may have significant impacts on supply and demand. The overall point being that there are a lot of inputs and a lot of actors in a complicated system.  Even if you focus just on news, there are many things that fall into that category. News does not come out at regular intervals and it does not necessarily spread evenly.  That alone could make for a highly variable environment. "I think ""Psychological Pricing"" is a similar phenomenon to what you are looking for.  This is where retailers use certain numbers in prices because those prices are more appealing to consumers.  Since stocks - and in your case bitcoin - have prices, they too will be more or less appealing at different prices based on psychology alone." I found the answer. It was the Stock Ticker that I was looking for. So, if I understand correctly the price at certain moment is the price of the latest sale and can be used to get a global picture of what certain stock is worth at that certain instant. There would be small generic risk that the company stock goes down real fast by more than 15% in a specific event to the company [fraud, segment company operates suffers a shock, etc] or a generic event to the stock market like recent events of Greece etc. "The process of borrowing shares and selling them is called shorting a stock, or ""going short.""  When you use money to buy shares, it is called ""going long."" In general, your strategy of going long and short in the same stock in the same amounts does not gain you anything.  Let's look at your two scenarios to see why. When you start, LOOT is trading at $20 per share.  You purchased 100 shares for $2000, and you borrowed and sold 100 shares for $2000.  You are both long and short in the stock for $2000.  At this point, you have invested $2000, and you got your $2000 back from the short proceeds.  You own and owe 100 shares. Under scenario A, the price goes up to $30 per share.  Your long shares have gone up in value by $1000.  However, you have lost $1000 on your short shares.  Your short is called, and you return your 100 shares, and have to pay interest.  Under this scenario, after it is all done, you have lost whatever the interest charges are. Under scenario B, the prices goes down to $10 per share.  Your long shares have lost $1000 in value.  However, your short has gained $1000 in value, because you can buy the 100 shares for only $1000 and return them, and you are left with the $1000 out of the $2000 you got when you first sold the shorted shares.  However, because your long shares have lost $1000, you still haven't gained anything.  Here again, you have lost whatever the interest charges are. As explained in the Traders Exclusive article that @RonJohn posted in the comments, there are investors that go long and short on the same stock at the same time.  However, this might be done if the investor believes that the stock will go down in a short-term time frame, but up in the long-term time frame.  The investor might buy and hold for the long term, but go short for a brief time while holding the long position. However, that is not what you are suggesting.  Your proposal makes no prediction on what the stock might do in different periods of time.  You are only attempting to hedge your bets.  And it doesn't work.  A long position and a short position are opposites to each other, and no matter which way the stock moves, you'll lose the same amount with one position that you have gained in the other position.  And you'll be out the interest charges from the borrowed shares every time. With your comment, you have stated that your scenario is that you believe that the stock will go up long term, but you also believe that the stock is at a short-term peak and will drop in the near future.  This, however, doesn't really change things much.  Let's look again at your possible scenarios. You believe that the stock is a long-term buy, but for some reason you are guessing that the stock will drop in the short-term.  Under scenario A, you were incorrect about your short-term guess.  And, although you might have been correct about the long-term prospects, you have missed this gain.  You are out the interest charges, and if you still think the stock is headed up over the long term, you'll need to buy back in at a higher price. Under scenario B, it turns out that you were correct about the short-term drop.  You pocket some cash, but there is no guarantee that the stock will rise anytime soon.  Your investment has lost value, and the gain that you made with your short is still tied up in stocks that are currently down. Your strategy does prevent the possibility of the unlimited loss inherent in the short.  However, it also prevents the possibility of the unlimited gain inherent in the long position.    And this is a shame, since you fundamentally believe that the stock is undervalued and is headed up.  You are sabotaging your long-term gains for a chance at a small short-term gain." A stock's price does not move in a completely continuous fashion.  It moves in discrete steps depending on who is buying/selling at given prices. I'm guessing that by opening bell the price for buying/selling a particular stock has changed based on information obtained overnight. A company's stock closes at $40.  Overnight, news breaks that the company's top selling product has a massive defect.  The next morning the market opens.  Are there any buyers of the stock at $40?  Probably not.  The first trade of the stock takes place at $30 and is thus, not the same as the previous day's close. "In fact, it's quite the opposite. If someone is willing to sell some stock as low as $30/share, and someone else is willing to pay $31/share, one of those individuals is going to get a good deal - unless HFT acts as the middle-man and snags the extra dollar. In which case the individuals get the worst price they would accept and someone with fast collocated computers gets to skim some profits (while adding no value, the order could have happened without the so called ""liquidity"" that HFT claims to add).  It's not exactly that simple, but that's the basic effect. It's an unnecessary middleman that skims profits away from individuals on both sides.  I would like to see a return to ""investing"" back to the meaning of the word, instead of gambling on daily or short-term fluctuations. I wouldn't mind a long-term holding requirement (3 months?) for every purchase, and a daily exchange-calculated set price (calculated by actual orders placed) that everyone who buys/sells a particular stock on a given day pays.  Yes, my ideas would destroy an entire industry. I'm ok with that because it would encourage people to *really* invest in companies." Yes, you've got it right.  The change in price is less meaningful as the instrument is further from the price of the underlying.  As the delta moves less, the gamma is much less. Gamma is to delta as acceleration is to speed.  Speed is movement relative to X, and acceleration is rate of change in speed.  Delta is movement relative to S, and gamma is the rate of change in delta. Delta changes quickly when it is around the money, which is another way of saying gamma is higher.  Delta is the change of the option price relative to the change in stock price.  If the strike price is near the market price, then the odds of being in or out of the money could appear to be changing very quickly - even going back and forth repeatedly. Gamma is the rate of change of the delta, so these sudden lurches in pricing are by definition the gamma.  This is to some extent a little mundane and even obvious.  But it's a useful heuristic for analyzing prices and movement, as well as for focusing analyst attention on different pricing aspects. You've got it right.  If delta is constant (zero 'speed' for the change in price) then gamma is zero (zero 'acceleration'). Also important to keep in mind is the difference in liquidity. The stock could be very liquid in 1 exchange but not in another. When times get bad, liquidity could dry up 1 one exchange, which results in a trading discount. If the company reported a loss at the previous quarter when the stock what at say $20/share, and now just before the company's next quarterly report, the stock trades around $10/share. There is a misunderstanding here, the company doesn't sell stock, they sell products (or services). Stock/share traded at equity market. Here is the illustration/chronology to give you better insight:   Now addressing the question What if the stock's price change? Let say, Its drop from $10 to $1 Is it affect XYZ revenue ? No why? because XYZ selling ads not their stocks the formula for revenue revenue = products (in this case: ads) * quantity the equation doesn't involve capital (stock's purchasing) The beta of a stock can be interpreted as the average relative movement of a stock with respect to the movement of a market index. In your case, the stock will move on average by 0.8. Thus over a longer time horizon, not on a daily, weekly basis. This can arise with very thinly traded stocks for large blocks of shares. If the market only has a few thousand dollars available at between 8.37 and 12.5 the price is largely meaningless for people who want to invest in hundreds of thousands/millions of dollars worth, as the quoted price can't get them anywhere near the number of shares they want. How liquid is the stock in question? As you point out, the moving average is just MA(k)t = (Pt-1 + … + Pt-k )/k and is applied in technical analysis (TA) to smooth out volatile (noise) price action. If it has any logic to it, you might want to think in terms of return series (Pt - Pt-1 / Pt-1) and you could hypothesize that prices are in fact predictable and will oscillate below and above a running moving average.  Below is a link to a study on MA trading rules, published in the Journal of Finance, with the conclusion of predictive power and abnormal returns from such strategies. As with any decision made upon historical arguments, one should be aware of structural changes and or data mining.  Simple  technical trading rules and the stochastic properties of stock  returns Brock, W., J. Lakonishok and B. Le Baron, 1992, Simple technical trading rules and the stochastic properties of stock returns, Journal of Finance, 47, 1731-64. MA rules betterthan chance in US stock market, 1897-1986 I don't know whether you are new to TA or not, but a great commercial site, with plenty of computer-generated signals is FinViz. "I would have to disagree with the other responders. In technical analysis of stock charts, various short and long term moving averages are used to give an indication of the trend of the stock in the short and long term, as compared to the current price. I would prefer to use the term moving average (MA) rather than average as the MA is recalculated every day (or at appropriate frequencies for your data) on the period you are using. I would also expand on the term ""moving average"". There are two that are commonly used Going back to the question, of the value of this number, For example if the current price is above the 200 day EWMA and also above the 30 day EWMA, then the stock is broadly trending upwards. Conversely if current price is below the 200 day EWMA and also below the 30 day EWMA, then the stock is broadly trending downwards. These numbers are chosen on the basis of the market you are trading in, the volatility and other factors. For another example of how a number of moving averages are used together, please have a read of Daryl Guppy's Multiple Moving Average, though this does not use moving averages as large as 200 days." Usually when a stock is up-trending or down-trending the price does not go up or down in a straight line. In an uptrend the price may go up over a couple of days then it could go down the next day or two, but the general direction would be up over the medium term. The opposite for a downtrend. So if the stock has been generally going up over the last few weeks, it may take a breather for a week or two before prices continue up again. This breather is called a retracement in the uptrend. The Fibonacci levels are possible amounts by which the price might retract before it continues on its way up again. By the way 50% is not actually a Fibonacci Retracement level but it is a common retracement level which is usually used in combination with the Fibonacci Retracement levels.