Satunnaiskävelyjä

Satunnaiskävelyjä, or random walks in English, are mathematical models that describe a path consisting of a succession of random steps. At each step, the direction and magnitude of the step are determined by some random variable. The concept is fundamental in probability theory and has wide-ranging applications in various fields.

A simple one-dimensional random walk can be visualized as a particle moving on a line. At each time interval, the particle has an equal probability of moving one step to the right or one step to the left. The position of the particle after a certain number of steps is a random variable. More complex random walks can occur in two or more dimensions, where the direction of each step is chosen from a set of possibilities.

The study of random walks has led to important insights in areas such as statistical mechanics, where they are used to model the diffusion of particles. In finance, random walk theory is applied to model stock price movements, suggesting that future price changes are unpredictable and independent of past movements. Computer science also utilizes random walks for algorithms like PageRank, used by Google to rank web pages. The behavior of a random walk, such as its expected distance from the origin or the probability of returning to the starting point, can be analyzed using mathematical tools.