Why IV and stock price are inversely related
"people are willing to pay higher premiums for options when stocks go down. Obviously the time value and intrinsic value and interests rates of the option doesn't change because of this so the miscalculation remainder is priced into the implied volatility part of the formula.  Basically, anything that suggests the stock price will get volatile (sharp moves in either direction) will increase the implied volatility of the option. For instance, around earnings reports, the IV in both calls and puts in the nearest expiration dates are very high. When stocks go down sharply, the volatility is high because some people are buying puts for protection and others are buying calls because they think there will be a rebound move in the other direction. People (the ""sleep-at-night"" investors, not the derivatives traders ;) )  tend to be calm when stocks are going up, and fearful when they are going down. The psychology is important to understand and observe and profit from, not to quantitatively prove. The first paragraph should be your qualitative answer"
"What you are seeking is termed ""Alpha"", the mispricing in the market. Specifically, Alpha is the price error when compared to the market return and beta of the stock. Modern portfolio theory suggests that a portfolio with good Alpha will maximize profits for a given risk tolerance. The efficient market hypotheses suggests that Alpha is always zero. The EMH also suggests that taxes, human effort and information propagation delays don't exist (i.e. it is wrong). For someone who is right, the best specific answer to your question is presented Ben Graham's book ""The Intelligent Investor"" (starting on page 280). And even still, that book is better summarized by Warren Buffet (see Berkshire Hathaway Letters to Shareholders). In a great disservice to the geniuses above it can be summarized much further: closely follow the company to estimate its true earnings potential... and ignore the prices the market is quoting. ADDENDUM: And when you have earnings potential, calculate value with: NPV = sum(each income piece/(1+cost of capital)^time) Update: See http://finance.fortune.cnn.com/2014/02/24/warren-buffett-berkshire-letter/ ""When Charlie Munger and I buy stocks..."" for these same ideas right from the horse's mouth" "It reminds me of the Efficient Market Hypothesis, except that just states in its weakest form that the current market price accounts for all information embedded in previous market prices. In other words, people buying today at 42 know it was selling for 40 yesterday, and the patterns and such. To say that stock is memoryless strikes me as not quite right -- to the extent that stocks are valued based on earnings, much of what we infer about future earnings relies on past and present earnings. One obvious counterexample to this ""memoryless"" claim is bankruptcy. If a stock files bankruptcy, and there isn't enough money to pay senior debt, your shares are worth 0 in perpetuity." "Your strategy fails to control risk. Your ""inversed crash"" is called a rally. And These kind of things often turn into bigger rallies because of short squeezes, when all the people that are shorting a stock are forced to close their stock because of margin calls - its not that shorts ""scramble"" to close their position, the broker AUTOMATICALLY closes your short positions with market orders and you are stuck with the loss. So no, your ""trick"" is not enough. There are better ways to profit from a bearish outlook." "The most fundamental answer is that when you short a stock (or an ETF), you short a specific number of shares on a specific day, and you probably don't adjust this much as the price wobbles goes up and down. But an inverse fund is not tied to a specific start date, like your own transaction is.  It adjusts on an ongoing basis to maintain its full specified leverage at all times.  If the underlying index goes up, it has to effectively ""buy in"" because its collateral is no longer sufficient to support its open position.  On the other hand, if the underlying index goes down, that frees up collateral which is used to effectively short-sell more of the underlying.  So by design it will buy high and sell low, and so any volatility will pump money out of the fund. I say ""effectively"" because inverse funds use derivatives and contracts, rather than actually shorting the underlying security.   Which brings up the less fundamental issue.  These derivatives and contracts are relatively opaque; the counter-parties are in it for their own benefit, not yours; and the people who run the fund get their expenses regardless of how you do, and they are hard for you to monitor.  This is a hazardous combination." Look at the how the income statement is built. The stock price is nowhere on it. The net income is based on the revenue (money coming in) and expenses (money going out).  Most companies do not issue stock all that often. The price you see quoted is third parties selling the stock to each other. There are those who would suggest that due to the Efficient Market Hypothesis, stocks are always fairly valued. Consider, if non-professional posters on SE (here) had a method that worked beyond random chance, everyone seeking such a method would soon know it. If everyone used that method, it would lose its advantage. In theory, this is how stocks' values remain rational.  That said, Williams %R is one such indicator. It can be seen in action on Yahoo finance -  In the end, I find such indicators far less useful than the news itself. BP oil spill - Did anyone believe that such a huge oil company wouldn't recover from that disaster? It recovered by nearly doubling from its bottom after that news. A chart of NFLX (Netflix) offers a similar news disaster, and recovery.  Both of these examples are not quantifiable, in my opinion, just gut reactions. A quick look at the company and answer to one question - Do I feel this company will recover? To be candid - in the 08/09 crash, I felt that way about Ford and GM. Ford returned 10X from the bottom, GM went through bankruptcy. That observation suggests another question, i.e. where is the line drawn between 'investing' and 'gambling'? My answer is that buying one stock hoping for its recovery is gambling. Being able to do this for 5-10 stocks, or one every few months, is investing. "Yes, the price of a stock is what investors think the value of a stock is, which is not tied to profits or dividends by any rigid formula. But to say that therefore the price could be high even though the company is doing very poorly is hypothetically true, but unlikely in practice. Consider any other product. There is no fixed formula for the value of a used car, either. If everyone agreed that a rusting, 20-year old car that doesn't run is worth $100,000, then that's what it would sell for. But that's a pretty big ""if"" at the beginning of that sentence.  If the car had been used in some hit TV show 20 years ago, or if it was owned by a celebrity, or some such special case, maybe a rusting old car really would sell for $100,000. Likewise, a stock might have a price higher than what one would predict from its dividends if some rich person wanted to buy that company because the brand name brings back nostalgic memories from his youth and so he drives the price up, etc. But the normal case is that, in the long term, the price of a stock tends to settle on a value proportional to the dividends that it pays. Or rather, and this is a big caveat, the dividends that investors expect it to pay in the future. And then adjusted for all sorts of other factors and special situations, like the value of the company if it was to be liquidated, etc." As said previously, most of the time volume does not affect stock prices, except with penny stocks. These stocks typically have a small volume in the 3 or 4 figure range and because of this they typically experience very sharp rises and drops in stock prices, contrasting normal stocks that go up and down constantly every minute. Volume is not one thing you should be looking at when analyzing a stock in most cases, since it is simply the number of people of trades made in a day. That has no effect on the value of the company, whereas looking at P/E ratios, dividend growth, etc all can be analyzed to see if a company is growing and is doing well in its field. If I buy an iPhone, it doesn't matter if 100 other people or 100,000 other people have bought it as well, since they won't really affect my experience with the product. Whereas the type of iPhone I buy will. Most of stock trading occurs on what is called a secondary market. For example, Microsoft is traded on NASDAQ, which is a stock exchange. An analogy that can be made is that of selling a used car. When you sell a used car to a third person, the maker of your car is unaffected by this transaction and the same goes for stock trading. Still within the same analogy, when the car is first sold, money goes directly to the maker (actually more complicated than that but good enough for our purposes). In the case of stock trading, this is called an Initial Public Offering (IPO) / Seasoned Public Offering (SPO), for most purposes. What this means is that a drop of value on a secondary market does not directly affect earning potential. Let me add some nuance to this. Say this drop from 20$ to 10$ is permanent and this company needs to finance itself through equity (stock) in the future. It is likely that it would not be able to obtain as much financing in this matter and would either 1) have to rely more on debt and raise its cost of capital or 2) obtain less financing overall. This could potentially affect earnings through less cash available from financing. One last note: in any case, financing does not affect earnings except through cost of capital (i.e. interest paid) because it is neither revenue nor expense. Financing obtained from debt increases assets (cash) and liabilities (debt) and financing obtained from stock issuance increases assets (cash) and shareholder equity. "I probably don't understand something. I think you are correct about that.  :) The main way money enters the stock market is through investors investing and taking money out. Money doesn't exactly ""enter"" the stock market.  Shares of stock are bought and sold by investors to investors.  The market is just a mechanism for a buyer and seller to find each other. For the purposes of this question, we will only consider non-dividend stocks. Okay. When you buy stock, it is claimed that you own a small portion of the company. This statement has no backing, as you cannot exchange your stock for the company's assets. For example, if I bought $10 of Apple Stock early on, but it later went up to $399, I can't go to Apple and say ""I own $399 of you, here you go it back, give me an iPhone."" The only way to redeem this is to sell the stock to another investor (like a Ponzi Scheme.) It is true that when you own stock, you own a small portion of the company.  No, you can't just destroy your portion of the company; that wouldn't be fair to the other investors.  But you can very easily sell your portion to another investor.  The stock market facilitates that sale, making it very easy to either sell your shares or buy more shares. It's not a Ponzi scheme.  The only reason your hypothetical share is said to be ""worth"" $399 is that there is a buyer that wants to buy it at $399.  But there is a real company behind the stock, and it is making real money. There are several existing questions that discuss what gives a stock value besides a dividend: The stock market goes up only when more people invest in it. Although the stock market keeps tabs on Businesses, the profits of Businesses do not actually flow into the Stock Market. In particular, if no one puts money in the stock market, it doesn't matter how good the businesses do. The value of a stock is simply what a buyer is willing to pay for it.  You are correct that there is not always a correlation between the price of a stock and how well the company is doing.  But let's look at another hypothetical scenario. Let's say that I started and run a publicly-held company that sells widgets.  The company is doing very well; I'm selling lots of widgets.  In fact, the company is making incredible amounts of money.  However, the stock price is not going up as fast as our revenues.  This could be due to a number of reasons: investors might not be aware of our success, or investors might not think our success is sustainable.  I, as the founder, own lots of shares myself, and if I want a return on my investment, I can do a couple of things with the large revenues of the company: I can either continue to reinvest revenue in the company, growing the company even more (in the hopes that investors will start to notice and the stock price will rise), or I can start paying a dividend.  Either way, all the current stock holders benefit from the success of the company." From every article I've encountered, the chicken and egg aspect suggests that IV is produced by looking at options pricing, and calculating the IV from that.  The implication is that whatever is known at that time is included in the price. And that when you see a particular option trade an unusual number of contracts at a given price, the implication is that someone thinks they know something that's not already priced in, i.e. that the current price is not accurate, they can profit on the future event. I was looking at NAT and NAO, NAT owns 20% of NAO.  They trade opposite each other on the price of oil, low is good for NAT, bad for NAO.  In bad times the other company's stock would probably rise, so they could trim excess shares to keep a stable monetary holding.  This would create cash in bad times, in good times they could buy more, creating a floor as well for the other. Companies do both quite often.  They have opposite effects on the share price, but not on the total value to the shareholders.  Doing both causes value to shareholders to rise (ie, any un-bought back shares now own a larger percentage of the company and are worth more) and drops the per-share price (so it is easier to buy a share of the stock).  To some that's irrelevant, but some might want a share of an otherwise-expensive stock without paying $700 for it. As a specific example of this, Apple (APPL) split its stock in 2014 and also continued a significant buyback program: Apple announces $17B repurchase program, Oct 2014 Apple stock splits 7-to-1 in June 2014. This led to their stock in total being worth more, but costing substantially less per share. I have heard that people say the greater earning means greater   intrinsic value of the company. Then, the stock price is largely based   on the intrinsic value. So increasing intrinsic value due to   increasing earning will lead to increasing stock price. Does this make   sense ? Yes though it may be worth dissecting portions here. As a company generates earnings, it has various choices for what it can do with that money. It can distribute some to shareholders in the form of dividends or re-invest to generate more earnings. What you're discussing in the first part is those earnings that could be used to increase the perceived value of the company. However, there can be more than a few interpretations of how to compute a company's intrinsic value and this is how one can have opinions ranging from companies being overvalued to undervalued overall. Of Mines, Forests, and Impatience would be an article giving examples that make things a bit more complex. Consider how would you evaluate a mine, a forest or a farm where each gives a different structure to the cash flow? This could be useful in running the numbers here. In my mind its not the same.   If growth is stock value then this is incorrect because of compound interest in stock price. $100 stock price after one year would be $105 and a dividend would be $2 Next year the stock would be  $110.20 (Compound Interest) and would the Dividend really go up in lock step with the stock price? Well probably not, but if it did then maybe you could call it the same. Even if the dollars are the same the growth rate is more variable than the dividends so its valuable to segregate the two. I am open to criticism, my answer is based on my personal experience and would love to hear contrary positions on this.