This presentation discusses cost drivers in COCOMO modeling, specifically personnel attributes. It defines five personnel cost drivers: ACAP (Analyst Capability), AEXP (Application Experience), PCAP (Programmer Capability), VEXP (Virtual Machine Experience), and LEXP (Programming Language Experience). Each cost driver is rated on a scale from very low to extra high, with associated multipliers to estimate their impact on project costs. Details are provided on how to assess each cost driver.