Estimation of Irregularly Sampled Random Processes
Generate a realization of an irregularly sampled OrnsteinUhlenbeckProcess.
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sample = TimeSeriesResample[
RandomFunction[
OrnsteinUhlenbeckProcess[0, .1, .3], {0, 100, .1}], {Sort[
RandomReal[100, 1000]]}]Out[1]=
show complete Wolfram Language input
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Estimate the process parameters from irregularly sampled data.
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EstimatedProcess[sample,
OrnsteinUhlenbeckProcess[\[Mu], \[Sigma], \[Theta]]]Out[3]=
Retrieve the stock prices for GE since January 1, 2013, and convert them to TemporalData .
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price = TemporalData[FinancialData["GE", "Jan. 1, 2013"]]Out[4]=
show complete Wolfram Language input
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The time stamp of the stock price data is nonuniform.
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MinMax[Differences[price["Times"]]]Out[6]=
Assume the log price satisfies FractionalBrownianMotionProcess and estimate the parameters.
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EstimatedProcess[Log[price],
FractionalBrownianMotionProcess[\[Mu], \[Sigma], h]]Out[7]=