Top Insider Purchases of the Week: Insider purchases are a lot more predictive than insider selling. Barron's lists companies where managers are buying stock, and we build a portfolio with those companies' shares. There has been interesting activity in Titan Machinery ( TITN), Superconductor Technologies ( SCON), Pier 1 Imports ( PIR) and Zion Oil & Gas ( ZN). Latest Activist Purchases: Which companies are the top hedge funds chasing? This week's list includes names like Texas Industries ( TXI), Celldex Therapeutics ( CLDX) and Dr Pepper Snapple Group ( DPS). Research Reports: The latest analyst research highlighted by Barron's, including reports this week on Lazard ( LAZ), Seattle Genetics ( SGEN) and City National ( CYN).