MELVYL MEDLINE DATABASES TELNET STATISTICS
                 Time period: 12/01/99 through 12/31/99


1.0  SUMMARY STATISTICS
_______________________

  Sessions:         Medical/Health/
                      Life Sciences   All Other
                          Libraries   Libraries      Remote       Total
                    _______________   _________   _________   _________
    Berkeley                      0         788       3,352       4,140
    Davis                       167       3,626       1,051       4,844
    Irvine                        0       3,294           0       3,294
    Los Angeles                   0       2,445       1,112       3,557
    Riverside                     0         132         413         545
    San Diego                   748       3,010         276       4,034
    San Francisco               731           0       8,467       9,198
    Santa Barbara                 0         149         215         364
    Santa Cruz                  149          55         275         479
    Stanford                                                      2,046
    Other (including DLA)         0           0       9,936       9,936
                    _______________   _________   _________   _________
    Total:                    1,795      13,499      25,097      42,437


  Relative use of MEDLINE databases

                       Number of     Number of        Number of
                       Sessions      FIND commands    Records Displayed
                       ________      _____________    _________________
    MED (current)        30,162           97,225              1,068,594
    MED90 database        5,712           13,106                 86,469
    MED85 database        2,920            5,952                 30,805
    MED80 database        1,867            3,597                 18,688
    MED75 database        1,067            2,092                 12,486
    MED66 database          709            1,501                  9,136


  Per hour usage:

          Time         Sessions            Finds      Records Displayed
    __________       __________       __________      _________________
    12-2  a.m.              493            1,207                 12,561
     2-4  a.m.              180              505                  4,928
     4-6  a.m.              139              421                  4,505
     6-8  a.m.              765            2,345                 21,124
     8-10 a.m.            4,561           13,187                116,412
    10-12 a.m.            8,424           23,766                215,472
    12-2  p.m.            7,734           22,136                232,830
     2-4  p.m.            9,127           26,604                274,473
     4-6  p.m.            6,026           17,466                176,410
     6-8  p.m.            2,490            7,381                 81,076
     8-10 p.m.            1,602            5,229                 47,680
    10-12 p.m.              896            3,226                 38,707
    __________       __________       __________      _________________
        Total:           42,437          123,473              1,226,178


  Session length (minutes:seconds):

                    Medical/Health/
                      Life Sciences   All Other
                          Libraries   Libraries      Remote       Total
                    _______________   _________   _________   _________
    Assist:
      Average                    0.0         0.0         0.0       0:00
      Median                     0.0         0.0         0.0       0:00
    Command:
      Average                 17:17       13:35       16:28       13:40
      Median                  11:21        8:30       11:12        8:30
    Total:
      Average                 17:17       13:35       16:28       13:40
      Median                  11:21        8:30       11:12        8:30


  Response time (in seconds):                                      Std.
                                                          Avg.     Dev.
                                                        ______   ______
    Search  - from receipt of command at DLA until         1.2      4.4
              transmission of response
    Display - from receipt of command at DLA until         0.1      0.2
              transmission of a complete screen

  Use of Assist vs Command mode:            Number of     Percentage of
                                             Sessions          Searches
                                            _________     _____________
    Assist mode                                     0              0.0%
    Command mode                               42,437              100%

  E MED option:
    E MED chosen from Welcome screen                        0
    E MED chosen from Assist screens                        0

    Specific screens chosen from within E MED:
      Master Menu                                           0
      FIND command                                          0
      FIND command examples                                 0
      DISPLAY command                                       0
      DISPLAY command - other options                       0
      BROWSE command                                        0
      BROWSE DISPLAY options                                0
      SELECT command                                        0
      Assistance commands                                   0
      START and END commands                                0
      Other commands                                        0
      Combine commands                                      0
      SHOW HISTORY command                                  0
      SAVE command                                          0
      COMMENT command                                       0


2.0 ASSIST MODE
________________

  Assist mode sessions as:                                  % of Campus
                                          % of Total     MELVYL MEDLINE
                                     Assist Sessions           Sessions
                                     _______________     ______________
    Berkeley                                    0.0%               0.0%
    Davis                                       0.0%               0.0%
    Irvine                                      0.0%               0.0%
    Los Angeles                                 0.0%               0.0%
    Riverside                                   0.0%               0.0%
    San Diego                                   0.0%               0.0%
    San Francisco                               0.0%               0.0%
    Santa Barbara                               0.0%               0.0%
    Santa Cruz                                  0.0%               0.0%
    Stanford                                    0.0%               0.0%
    Other                                       0.0%               0.0%

                                                             % of Group
                                          % of Total     MELVYL MEDLINE
                                     Assist Sessions           Sessions
                                     _______________     ______________
    Medical/Health/Life Sciences                0.0%               0.0%
    All Other Libraries                         0.0%               0.0%
    Remote                                      0.0%               0.0%


  SEARCH information:

    Average number of searches completed per session      0.0
    Retrievals per search - average                       0.0
    Retrievals per search - median                        0.0
    Retrievals per search - standard deviation            0.0
    Percent of searches completed with 0 results          0.0%


  COMMANDS entered, by type, excluding errors:
                                                               % of all
                                                   Total       Commands
                                              __________     __________
    FIND                                               0           0.0%
    DISPLAY (excluding automatic displays)             0           0.0%
    BROWSE SU                                          0           0.0%
    SELECT                                             0           0.0%
    HELP                                               0           0.0%
    SAVE                                               0           0.0%
    ADD-ON (AND, OR)                                   0           0.0%
    LOGON or LOGOFF                                    0           0.0%


  FINDS completed:                                  RETRIEVALS PER NON-
                          TOTAL    ZERO RESULTS    ZERO RESULT SEARCHES
                  _____________  ______________  ______________________
                           % of            % of
                            all         all for                    Std.
                     No.  FINDs     No.   Index  Median    Avg.    Dev.
                  ______ ______  ______ _______  ______ _______ _______
  By index:
  PERSONAL AUTH        0   0.0%       0    0.0%       0     0.0     0.0
  TITLE WORD           0   0.0%       0    0.0%       0     0.0     0.0
  KEYWORD              0   0.0%       0    0.0%       0     0.0     0.0
  DATE                 0   0.0%       0    0.0%       0     0.0     0.0
  LANGUAGE             0   0.0%       0    0.0%       0     0.0     0.0
  EXACT SUBJECT        0   0.0%       0    0.0%       0     0.0     0.0

  By number of indexes:
  Multiple             0   0.0%       0    0.0%       0     0.0     0.0
  Single               0   0.0%       0    0.0%       0     0.0     0.0


  LIMITS:

    Number of times limits (bit strings) used:              0

    Use by bit string (percentage):
      Current year                                       0.0%
      English Language                                   0.0%
      XS Aged                                            0.0%
      XS Animal                                          0.0%
      XS Case Report                                     0.0%
      XS Child                                           0.0%
      XS Female                                          0.0%
      XS Human                                           0.0%
      XS Male                                            0.0%
      PT Review                                          0.0%


  BOOLEAN:

    Number of searches with Booleans:                       0
      (FIND, BROWSE, SELECT, ADD-ON)

    Percentage of ANDs                                   0.0%
    Percentage of ORs                                    0.0%


  DISPLAY commands, by type, excluding automatic displays:

    REVIEW                                               0.0%
    BRIEF                                                0.0%
    LONG                                                 0.0%
    TITLE/SUBJECT                                        0.0%


3.0 COMMAND MODE
________________

  SEARCH information:

    Average number of searches completed per session      2.9
    Retrievals per search - average                     660.7
    Retrievals per search - median                        8.0
    Retrievals per search - standard deviation         6560.7
    Percent of searches completed with 0 results         20.9%

    Percent of searches entered that are long             0.3%
    Percent of long searches completed                   60.0%

  COMMANDS entered, by type, excluding errors:
                                                               % of all
                                                   Total       Commands
                                              __________     __________
    FIND                                          94,570          25.5%
    DISPLAY (excluding automatic displays)       130,203          35.2%
    BROWSE                                         1,614           0.4%
    SELECT                                         1,195           0.3%
    HELP                                           3,103           0.8%
    EXPLAIN                                        2,708           0.7%
    SAVE                                          27,474           7.4%
    SET/RESET                                     19,499           5.3%
    SHOW                                           1,296           0.4%
    ADD-ON (AND, OR, AND NOT)                     23,412           6.3%
    LOGON or LOGOFF                               47,870          12.9%
    COMMENT                                            2           0.0%
    OTHER                                         17,294           4.7%


  FINDS completed:                                  RETRIEVALS PER NON-
                          TOTAL    ZERO RESULTS    ZERO RESULT SEARCHES
                _______________  ______________  ______________________
                           % of            % of
                            all         all for                    Std.
                     No.  FINDs     No.   Index  Median    Avg.    Dev.
                ________ ______  ______ _______  ______ _______ _______
  By index:
  PERSONAL AUTH   40,380  30.8%   8,450   20.9%      11   107.1   672.9
  TITLE WORD      14,744  11.2%   4,573   31.0%       8   342.2  2121.6
  EXACT TITLE      1,532   1.2%     743   48.5%       1    29.5   177.3
  JOURNAL          5,744   4.4%   1,818   31.6%     120  1835.9 12290.7
  EXACT JOURNAL    1,832   1.4%     513   28.0%     287  1571.1  3325.1
  PERIODICAL           0   0.0%       0    0.0%       0     0.0     0.0
  EXACT PE             0   0.0%       0    0.0%       0     0.0     0.0
  KEYWORD         47,290  36.1%   8,968   19.0%      28  1252.0  9746.7
  SUBJECT WORD       150   0.1%      60   40.0%     421 20126.7 58233.6
  SUBJECT          3,563   2.7%   1,371   38.5%     162  3095.4 12220.1
  MAJOR SUBJECT      475   0.4%      87   18.3%     106  1060.5  2906.3
  EXACT SUBJECT    1,465   1.1%     260   17.7%     108  1352.2  6347.7
  MAJOR XS           212   0.2%      42   19.8%     274  1797.8  4085.9
  EXPLODE XS         758   0.6%     104   13.7%     135  6022.5 22998.0
  EXPLODE MAJOR       62   0.0%       5    8.1%     130  1361.2  2944.7
  TREE NUMBER          0   0.0%       0    0.0%       0     0.0     0.0
  MAJOR TREE NUMBER    0   0.0%       0    0.0%       0     0.0     0.0
  DATE             5,411   4.1%     843   15.6%      10   154.6   774.6
  LANGUAGE         3,394   2.6%     155    4.6%      79   595.2     0.0
  PUB TYPE         1,599   1.2%     117    7.3%      34   586.7  3737.9
  Other indexes    2,080   1.6%     249   12.0%       1    41.2   283.7

  By number of indexes:
  Multiple        36,865  31.4%   8,342   22.6%      10   407.4  6712.6
  Single          80,677  68.6%  16,536   20.5%      27  1079.6  7879.1


  BROWSES completed:                                RETRIEVALS PER NON-
                          TOTAL    ZERO RESULTS    ZERO RESULT SEARCHES
                  _____________  ______________  ______________________
                           % of            % of
                            all         all for                    Std.
                     No.   BROs     No.   Index  Median    Avg.    Dev.
                  ______ ______  ______ _______  ______ _______ _______
  By index:
  PERSONAL AUTH       66   4.1%      10   15.2%       4    50.4   125.9
  JOURNAL            308  19.3%      65   21.1%       2     6.2    13.4
  EXACT JOURNAL       80   5.0%      26   32.5%       1     2.6     5.6
  SUBJECT          1,053  65.9%     225   21.4%       2    42.4   446.4
  EXACT SUBJECT       92   5.8%      29   31.5%       1     1.5     3.8
  TREE NUMBER          0   0.0%       0    0.0%       0     0.0     0.0

  By number of indexes:
  Multiple             0   0.0%       0    0.0%       0     0.0     0.0
  Single           1,599   100%     355   22.2%       2    31.9   365.5


  LIMITS:

    Number of times limits (bit strings) used:          6,973

    Use by bit string (percentage):
      Current year minus 5                               0.4%
      Current year minus 4                               0.0%
      Current year minus 3                               1.7%
      Current year minus 2                               0.4%
      Current year minus 1                               0.4%
      Current year                                       0.4%
      English Language                                  52.7%
      French Language                                    0.0%
      Japanese Language                                  0.0%
      German Language                                    0.0%
      Russian Language                                   0.0%
      XS Abstract                                        0.7%
      XS Adolescence                                     0.1%
      XS Adult                                           0.1%
      XS Aged                                            0.8%
      XS Animal                                          0.0%
      XS Case Report                                     0.1%
      XS Child                                           0.4%
      XS Comparative Studies                             0.0%
      XS English Abstract                                0.0%
      XS Female                                          0.3%
      XS Human                                           9.5%
      XS Infant                                          0.0%
      XS Infant, Newborn                                 0.0%
      XS Male                                            0.0%
      XS Mice                                            0.0%
      XS Middle Age                                      0.0%
      XS Rats                                            0.1%
      XS Support Non-U.S. Govt                           0.0%
      XS Support U.S. Govt, Non-P.H.S.                   0.0%
      XS Support U.S. Govt, P.H.S.                       0.0%
      PT Review                                         26.6%
      PT Journal Article                                 0.1%
      SUBSET AIM                                         4.9%
      SUBSET Indexing priority 1,2                       0.0%
      SUBSET Nursing journals                            0.3%
      SUBSET Dental journals                             0.0%
      SUBSET Cancer core journals                        0.0%

  BOOLEAN:

    Number of searches with Booleans:                  42,770
      (FIND, BROWSE, SELECT, ADD-ON)

    Percentage of ANDs                                  96.3%
    Percentage of ORs                                    2.7%
    Percentage of AND NOTs                               1.0%


  DISPLAY commands, by type, excluding automatic displays:

    REVIEW                                               2.0%
    BRIEF                                               64.7%
    LONG                                                 0.8%
    MEDLINE                                              1.1%
    FIELDS                                               2.8%
    PERIODICALS                                          0.0%
    BROWSE REVIEW                                        0.8%
    BROWSE LONG                                          0.4%
    BROWSE FIELDS                                        0.0%
    BROWSE MEDLINE                                       0.0%
    Other                                               27.3%

4.0  Error, EXPLAIN, HELP statistics (ASSIST & COMMAND)
_______________________________________________________

  Percent of commands that contained errors              9.5%

  Ten most frequent errors:
    1. NS command - no next screen                      39.7%
    2. First word of command is invalid                 26.9%
    3. FIND command with invalid index name              6.2%
    4. DISPLAY command contains invalid word             3.8%
    5. PS command - no previous screen                   2.2%
    6. Valid command at an inappropriate time            1.7%
    7. Add-on search with invalid index name             1.7%
    8. Search term missing from search command           1.6%
    9. NS of SHOW/EXP command-no next screen             1.5%
   10. DISPLAY command-record numbers too large          1.1%
   11. All others                                       13.7%


  Ten most frequent EXPLAIN requests:
    1. LOCATE (article dbs w/o monographs)              14.7%
    2. BOOKS DATABASE                                   13.0%
    3. FIND                                              8.5%
    4. MEDLINE BACKFILES                                 7.3%
    5. Unrecognized term                                 6.1%
    6. COMMANDS                                          5.9%
    7. DATABASES                                         3.8%
    8. ADD-ON SEARCH                                     3.5%
    9. INDEXES                                           3.5%
   10. DISPLAY                                           3.1%
   11. All others                                       30.7%


  Ten most frequent HELP situations:
    1. Command mode selected from Welcome               19.5%
    2. First word of command is invalid                 15.1%
    3. DISPLAY command-first of >1 screen                7.3%
    4. FIND command with invalid index name              6.2%
    5. DISPLAY command - middle of >1 screen             5.2%
    6. FIND command retrieves >1 book                    4.5%
    7. NS command - no next screen                       3.8%
    8. DISPLAY command - last of >1 screen               3.1%
    9. FIND command with zero results                    2.3%
   10. DISPLAY command-complete in one screen            2.3%
   11. All others                                       30.7%


  Ten most frequent SHOW requests:
    1. HISTORY                                          62.0%
    2. SEARCH                                           15.8%
    3. MAIL STATUS                                      10.5%
    4. MEDLINE GLOSSARY                                  2.1%
    5. SETTINGS                                          2.0%
    6. MAIL SETTINGS                                     1.3%
    7. MEDLINE NEWS                                      1.0%
    8. UPDATE                                            1.0%
    9. DATABASES                                         0.5%
   10. DISPLAY                                           0.4%
   11. All others                                        3.3%
MEDmm/dd med      MELVYL MEDLINE DATABASES TELNET STATISTICS (weekly)