[likelihood_ratio_process] Add new sections on distribution discrepency measures and Blume and Easley 2006 (#495)

* Tom's July 20 edits of likelihood ratio processes lecture

* updates

* Tom's July 21 edits of the likelihood ratio lecture

* updates

* minor updates

* minor title edits

* Tom's edits of likelihood ratio lecture, July 22

* Tom's July 23 edits of likeliood ratio process lecture

* updates

* updates

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Co-authored-by: thomassargent30 <ts43@nyu.edu>

Author: HumphreyYang

lectures/_static/quant-econ.bib

@@ -2,6 +2,35 @@
 QuantEcon Bibliography File used in conjuction with sphinxcontrib-bibtex package
 Note: Extended Information (like abstracts, doi, url's etc.) can be found in quant-econ-extendedinfo.bib file in _static/
 ###
+@book{friedman1953essays,
+  title={Essays in positive economics},
+  author={Friedman, Milton},
+  year={1953},
+  publisher={University of Chicago press}
+}
+
+@article{alchian1950uncertainty,
+  title={Uncertainty, evolution, and economic theory},
+  author={Alchian, Armen A},
+  journal={Journal of political economy},
+  volume={58},
+  number={3},
+  pages={211--221},
+  year={1950},
+  publisher={The University of Chicago Press}
+}
+
+
+@article{blume2006if,
+  title={If you're so smart, why aren't you rich? Belief selection in complete and incomplete markets},
+  author={Blume, Lawrence and Easley, David},
+  journal={Econometrica},
+  volume={74},
+  number={4},
+  pages={929--966},
+  year={2006},
+  publisher={Wiley Online Library}
+}
 
 @article{mendoza1998international,
   title={The international ramifications of tax reforms: supply-side economics in a global economy},