Parameter Estimation from Quantity Data
Get the lengths of major rivers in North America in miles.
In[1]:=

data = Quantity[ExampleData[{"Statistics", "RiverLengths"}], "Miles"];
In[2]:=

h = Histogram[data, 30, PDF, Frame -> True, FrameLabel -> Automatic,
PlotTheme -> "Detailed"]
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EstimatedDistribution accepts quantity data and returns QuantityDistribution with the units of the data.
In[3]:=

edist1 = EstimatedDistribution[data,
InverseGammaDistribution[a, b, c, d]]
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Estimate model in different units.
In[4]:=

edist2 = EstimatedDistribution[data,
QuantityDistribution[InverseGammaDistribution[a, b, c, d],
"Kilometers"]]
Out[4]=

Convert the first model to kilometers.
In[5]:=

UnitConvert[edist1, "Kilometers"]
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Plot the data histogram together with the fitted model PDF.
In[6]:=

Show[h, Plot[PDF[edist1, Quantity[x, "Miles"]], {x, 0, 2000}]]
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