  Modeling financial data often relies on assumptions that may prove
insufficient or unrealistic in practice. The Geometric Brownian Motion (GBM)
model is frequently employed to represent stock price processes. This study
investigates whether the behavior of weekly and monthly returns of selected
equities listed on the Ghana Stock Exchange conforms to the GBM model.
Parameters of the GBM model were estimated for five equities, and forecasts
were generated for three months. Evaluation of estimation accuracy was
conducted using mean square error (MSE). Results indicate that the expected
prices from the modeled equities closely align with actual stock prices
observed on the Exchange. Furthermore, while some deviations were observed, the
actual prices consistently fell within the estimated confidence intervals.
