Hi,

I am trying to Match the companies in my dataset that belong to the test sample 1:1 to a company out of that sample. To explain, the test sample was involved in Tax Disputes between 2003 and 2009, the control group was not. For each firm-year the dummy tax_disputes indicates whether this company was involved or not. Matching needs to be based on (1) industry classification; (2) firm size; and (3) time (YEAR). In particular, we identify non-tax-avoidant firms in the same four-digit North American Industry Classification Scheme industry as a given tax-avoidant firm in the year of the tax dispute. Matched firms need to have a market value (SIZE) of +-40% from each other. When multiple are possible, the one with the closest market value will be chosen.

Can anybody help me how to do this.