James Chen (Work Log)
06/11/2018 - Worked with Wei to get him set up with system
02/02/2017 - Planned immediate next steps for LBO project; fixed bug in matching code (matchpair indices not being stored correctly)
09/06/2016 - Discussed workload for the week, plan for project going forward with Ed and Jake.
09/08/2016 - Reread Lerner article, compiled notes on article and state of the project
09/09/2016 - Completed some ad hoc analyses of STATA dataset to diagnose problems with propensity score matching.
10/13/2016 - Met with Ed and Brian to discuss results and future work for LBO Innovation project. Began rebuild/redocumentation of dataset.
10/14/2016 - Continuing rebuild, documentation at Leveraged_Buyout_Innovation_(Academic_Paper)#New_Version. COMPUSTAT data is now standardized for linking.
10/18/2016 - Began importing Brian's SDC data into SQL database
10/20/2016 - Completed importing SDC data
10/21/2016 - Matched SDC data to COMPUSTAT data for LBO entry flags.
10/27/2016 - Reorganized SQL script for better readability. Tried to bugfix SDC join (still WIP)
10/28/2016 - Completed initial SDC join. Adding additional matches using name-based matching.
11/03/2016 - Continued working on name-based matching.
11/04/2016 - Completed name-based matching for SDC data/LBOs.
11/10/2016 - Finalized documentation for LBO side of project. Minor bugfixes for name-based matching from last week.
11/11/2016 - Worked on matching in patent flows and stocks, basically finished up to name-based matching
11/17/2016 - Finished matching in patent flows and stocks, contingent on having a completed active patent start/end table from Napas
11/18/2016 - Minor bugfixes for STATA code (got winsorized variables working consistently); began working on patent start/end table
07/15/2016 - Refining hazard model: revising variables used, comparing Cox Proportional Hazard and Lognormal Accelerated Failure Time models
07/18/2016 - Cataloged SQL tables, revised STATA script (STATAdatasetup2.do) to include ratios, replace cashflow with ebitda, and filter out firms smaller than $50 million
07/19/2016 - Investigated baseline hazard of Cox Proportional Hazard model. Compared to Lognormal and Loglogistic Accelerated Failure Time models to try to predict hazard rate (not just hazard ratio)
07/20/2016 - Adjusted dataset to filter out firms that are small (<$40m) or not listed in major exchanges (AMEX, NYSE, NASDAQ). Consulted Brian on descriptive statistics of dataset.
07/21/2016 - Investigated negative ebitda ratios.
07/22/2016 - Performed further testing of hazard model. Ran preliminary matching analysis using patent flow data.
07/25/2016 - Cleaned data setup do file. Organized list of data problems to consult with Ed.