*INCIDENTS OCCURRING DURING THE MIDNIGHT HOUR*.
**********************************************
*Does the number of incidents supposedly occurring
*during the midnight hour seem reasonable given the
*data set under consideration?
***********************************************.
*According to the FBI Data Collection Guidelines,
*the incident date/hour variable represents the
*month, day, year, and hour when the incident
*occurred or started, or the beginning of a time
*period, if appropriate.  If the incident date is
*unknown, then the report date is to be used with
*an indicator of “R”.  If the incident hour is
*unknown, then that portion of the incident date/hour
*variable is to be left blank. Zero, which is supposed
*to represent the midnight hour, might be used mistakenly
*to report missing or unknown data.  The aggregated
*flat file, in which the existing values for incident
*hour (INC_HR) were converted to numeric values, is used
*for this example.  The value for the midnight hour after
*the AGGREGATE command is 0 (zero).  See Extracting Data
*From Incident-Based Reporting Systems And NIBRS / Preparing
*A File For Analysis / Creating An Incident-Level Aggregated
*Flat File.
**************************************************.
*Preparing the Administrative Segment File
**************************************************
*Defining the Midnight Hour and Generating Comparative
*Line Graphs
**************************************************.
*This data quality check procedure can be performed against
*an aggregated flat file or the administrative data segment
*at the local, state, or national level. For the current
*example we use the National 1999 Administrative Segment
*data and focus on only those records for which an actual,
*as opposed to reported, incident date and time were recorded.
*Once the data file is retrieved, the first TEMPORARY / SELECT IF
*excludes those incidents for which the report date and time
*rather than the actual date and time were recorded. To view
*the results, a line graph with hour as the x-axis is produced.
*MISSING = EXCLUDE eliminates the records with no data in the
*time variables.
***************************************************. 
GET FILE=’Directory:\Path\Agency Data.sav’.
TEMPORARY.
SELECT IF (rptdate = ' ').
GRAPH
  /LINE(SIMPLE)=COUNT BY inc_hr
  /MISSING=EXCLUDE.
***************************************************
*For comparison purposes, a second TEMPORARY / SELECT IF
*excludes those incidents for which the report date and time
*rather than the actual date and time were recorded but also
*identifies those records for which only incident times greater
*than zero are reported.   This will show incident times other
*than the midnight hour.  A comparable line graph is generated
*and, again, the records with no data RPTDATE variable are
*excluded.  This retains only records with the actual date and
*time reported on the administrative segment.
****************************************************.
TEMPORARY.
SELECT IF (rptdate = ' ' and inc_hr gt 0).
GRAPH
  /LINE(SIMPLE)=COUNT BY inc_hr
  /MISSING=EXCLUDE.