Has the Marxist Labor Theory of Value Become Obsolete? Is it currently used for anything? Marx does not specify labor value, I believe he only uses the argument of surplus value according to the labor theory of value because that was the argument he found. He already started from the premise of finding an error in the system, if he didn't use that argument he would find another justification to criticize.
Has the Marxist Labor Theory of Value Become Obsolete? Is it currently used for anything?
The labor theory of value is no longer used in current economic research. You will not find it in conventional textbooks such MWG Microeconomic Theory or Varian Microeconomic Analysis. Nor will you find papers published in good journals relying on models using labor theory of value. In fact labor theory of value was not really widely used in the field for over 200 years. You can only find labor theory in some fringe not generally accepted research nowadays.
Also it is not a Marxist theory, labor theory of value is actually a classical theory developed by Smith & Ricardo (see Brue & Grant The History of Economic Thought). Marx used labor theory of value because that was the generally accepted theory of value during Marx's lifetime.