(I) The ‘normal’ vibrations in price, for example, due to a
temporary imbalance between supply and demand, changes in capitalization
rates, changes in the economic outlook, or other new information that causes
marginal changes in the stock’s value. In essence, the impact of such information
per unit time on the stock price is to produce a marginal change in the price
(almost certainly). This component is modeled by a standard geometric Brownian
motion with a constant variance per unit time and it has a continuous sample
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