ICPSR PROCESSING INFORMATION

                         ICPSR PROCESSING INFORMATION


     The data collection was processed according to the standard ICPSR
     processing procedures. The data were checked for illegal code values,
     and documentation missing from the NES Study Staff version of the
     codebook was added to the ICPSR version. Since the NES Study Staff
     release of the dataset, a new variable, Days Alive (V30), has been
     added, and the Control Identification Number (V102) has been changed.
     See the codebook documentation for more detailed explanations of
     these variables.

     Data are available in both logical record and card-image format. A data
     map documenting the column locations for both versions of the data is
     included at the back of the codebook. ICPSR has also added a Frequencies
     Addendum to the codebook, with frequencies for all variables except the
     Case Identification number (V1), Days Alive (V30), the Cluster ID
     (V102), and all alphabetic variables (V7, V22, V25, V26, and V29).