.  reghdfe CU did lnsize roa lev growth lnage soe dual lnDBOARD lnID lnSBOARD sfee mfee ffee,absorb(year industry provinc
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> e)
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(dropped 1 singleton observations)
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                assert():  3498  assertion is false
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BipartiteGraph::init_zigzag():     -  function returned error
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FixedEffects::estimate_dof():     -  function returned error
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                 <istmt>:     -  function returned error
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r(3498);
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