In door to door surveys, a technique for gathering a random sample of households after starting at a particular point. E.g. turning left after leaving the first house, walking anti-clockwise around the block and trying to interview somebody at every fourth house. Notice that, though it's called a random walk, the selection of households follows a clear rule.
A walk in one or more dimensions that is dictated by the outcome of a coin toss. The direction of each step of the walk is specified by the coin toss. The resulting random motion is often referred to as Brownian motion.
Price changes in securities that are (a priori) purely random. Expected behaviour in efficient markets.... more on: Random walk
The theory that stock prices are unpredictable.
A theory that contends there is an "efficient" price level for any stock. That all information about a stock has become so well known that the price on the market represents true value. The theory had been hurt considerably by the October, 1987 market sell off, and even "random walkers" say some stocks are still underpriced because of insufficient market information on them.
a deviation from an expected outcome
a discrete fractal, but Brownian motion is a true fractal, and there is a connection between the two
a mathematical model for molecular motion
a model for such physical processes as the Brownian motion of a small particle suspended in a liquid
Brownian motion, where the previous change in the value of a variable is unrelated to future or past changes
Theory that stock price changes from day to day are at random; the changes are independent of each other and have the same probability distribution. Many believers of the random walk theory believe that it is impossible to outperform the market consistently without taking additional risk.
Is the financial theory that asserts that changes in price or rate time series are unpredictable. However, the theory recognizes that there is a statistical interdependency between the data. This non-random stickiness is sometimes referred to as autocorrelation or serial correlation.
A key element in efficient market theory is that, in the short term, the behaviour of share prices is entirely random, responding to such unpredictable factors as investors' mood. Benjamin Graham referred to this aspect of investor behaviour as Mr Market, a character who behaved in a wild and unpredictable manner. Warren Buffett summed it up memorably when he said that investing in a publicly quoted stock was like going into partnership with a manic-depressive.
A current theory which holds that price movements cannot be predicted from past history or trends, and that future market values will be determined by totally random factors that cannot be defined through either technical or fundamental analysis.
a term used to describe the way prices of stock move, where the next movement cannot be predicted on the basis of previous movements
"Efficient market theory".
A walk in one or more dimensions that is dictated by the outcome of some random source.
A stock market theory that hypothesizes that past prices are of no use in forecasting future price movements. The theory maintains that prices move in a random pattern and that they are no more predictable than the walking pattern of a wandering person. This directly contradicts technical analysts' use of charts to forecast stock prices. See: Chartist; Technical Analysis
Theory that market prices move randomly around a main trend, in other words, that the volatility is arbitrary.
A theory which assumes that the future price movement of a security can not be predicted from past price movement (directly refuting technical analysts' use of charts as a method of forecasting stock prices). In effect, the theory argues that prices move in a random pattern and that they are no more predictable than the waling pattern of a drunken person.
An economic theory that price movements in the commodity futures markets and in the securities markets are completely random in character (i.e., past prices are not a reliable indicator of future prices).
the theory that, in the long term, investors cannot beat market averages
An economic theory that market price movements move randomly. This assumes an efficient market. The theory also assumes that new information comes to the market randomly. Together, the two assumptions imply that market prices move randomly as new information is incorporated into market prices. The theory implies that the best predictor of future prices is the current price, and that past prices are not a reliable indicator of future prices. If the random walk theory is correct, Technical Analysis cannot work.
In mathematics, computer science, and physics, a random walk, sometimes called a "drunkard's walk," is a formalisation of the intuitive idea of taking successive steps, each in a random direction.