Inversion method for generating random variates.

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Suppose you have a cdf

$$ F(X)=\frac{1}{2} (x-1)^3 + \frac{1}{2} $$

$$ 0\leq x\leq 2 $$

How, would one find the inversion to create random variants?

I tried rearranging and inverting the equation into

$$ X=(2u-1)^\frac{1}{3}+1 $$

$$ 0\leq u\leq 1 $$

Graphing this inverted equation clearly only show half of the equation. I am not sure how to get the second half. Thanks :D

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You inverted the equation correctly. Unfortunately you didn’t show the graph you obtained that seemed to indicate a problem, so it’s hard to say what went wrong. Just in case you used Wolfram|Alpha to plot the inverse function, note that by default the principal root is used, which yields this graph, but when you click on “Use the real-valued root instead” you get this graph, which is what you want for the inversion method.