MELVYL MEDLINE DATABASES TELNET STATISTICS                       
                 Time period: 02/01/99 through 02/28/99                         
                                                                                
                                                                                
1.0  SUMMARY STATISTICS                                                         
_______________________                                                         
                                                                                
  Sessions:         Medical/Health/                                             
                      Life Sciences   All Other                                 
                          Libraries   Libraries      Remote       Total         
                    _______________   _________   _________   _________         
    Berkeley                      0       2,558       6,978       9,536         
    Davis                       325       8,086       1,802      10,213         
    Irvine                        0       6,682           0       6,682         
    Los Angeles                   0       5,423       2,985       8,408         
    Riverside                     1         586         794       1,381         
    San Diego                 1,391       5,722       1,180       8,293         
    San Francisco               788           0      17,392      18,180         
    Santa Barbara                 0         464         702       1,166         
    Santa Cruz                  352         201         811       1,364         
    Stanford                                                      6,143         
    Other (including DLA)         0           0      19,861      19,861         
                    _______________   _________   _________   _________         
    Total:                    2,857      29,722      52,505      91,227         
                                                                                
                                                                                
  Relative use of MEDLINE databases                                             
                                                                                
                       Number of     Number of        Number of                 
                       Sessions      FIND commands    Records Displayed         
                       ________      _____________    _________________         
    MED (current)        66,359          235,417              2,628,199         
    MED90 database       10,387           23,901                174,859         
    MED85 database        6,337           13,812                 86,765         
    MED80 database        4,022            8,768                 47,271         
    MED75 database        2,474            4,936                 29,202         
    MED66 database        1,648            3,723                 28,130         
                                                                                
                                                                                
  Per hour usage:                                                               
                                                                                
          Time         Sessions            Finds      Records Displayed         
    __________       __________       __________      _________________         
    12-2  a.m.            1,054            3,507                 45,567         
     2-4  a.m.              397            1,347                 15,047         
     4-6  a.m.              360            1,114                 11,593         
     6-8  a.m.            1,553            4,461                 46,404         
     8-10 a.m.            8,932           26,764                256,923         
    10-12 a.m.           16,376           50,396                505,206         
    12-2  p.m.           16,419           51,251                518,532         
     2-4  p.m.           18,979           60,275                612,619         
     4-6  p.m.           13,874           44,498                467,781         
     6-8  p.m.            6,492           21,644                242,728         
     8-10 p.m.            4,089           14,731                152,406         
    10-12 p.m.            2,702           10,569                119,620         
    __________       __________       __________      _________________         
        Total:           91,227          290,557              2,994,426         
                                                                                
                                                                                
  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                 15:07       14:00       14:32       13:54         
      Median                   9:25        8:15        7:59        8:14         
    Total:                                                                      
      Average                 15:07       14:00       14:32       13:54         
      Median                   9:25        8:15        7:59        8:14         
                                                                                
                                                                                
  Response time (in seconds):                                      Std.         
                                                          Avg.     Dev.         
                                                        ______   ______         
    Search  - from receipt of command at DLA until         1.5      5.2         
              transmission of response                                          
    Display - from receipt of command at DLA until         0.2      0.3         
              transmission of a complete screen                                 
                                                                                
  Use of Assist vs Command mode:            Number of     Percentage of         
                                             Sessions          Searches         
                                            _________     _____________         
    Assist mode                                     0              0.0%         
    Command mode                               91,227              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      3.2                   
    Retrievals per search - average                     729.6                   
    Retrievals per search - median                       10.0                   
    Retrievals per search - standard deviation         6475.4                   
    Percent of searches completed with 0 results         21.6%                  
                                                                                
    Percent of searches entered that are long             0.3%                  
    Percent of long searches completed                   47.5%                  
                                                                                
  COMMANDS entered, by type, excluding errors:                                  
                                                               % of all         
                                                   Total       Commands         
                                              __________     __________         
    FIND                                         230,754          25.7%         
    DISPLAY (excluding automatic displays)       329,597          36.7%         
    BROWSE                                         4,205           0.5%         
    SELECT                                         2,879           0.3%         
    HELP                                          10,868           1.2%         
    EXPLAIN                                        7,917           0.9%         
    SAVE                                          63,342           7.1%         
    SET/RESET                                     45,656           5.1%         
    SHOW                                           3,477           0.4%         
    ADD-ON (AND, OR, AND NOT)                     51,239           5.7%         
    LOGON or LOGOFF                              107,974          12.0%         
    COMMENT                                            9           0.0%         
    OTHER                                         39,054           4.4%         
                                                                                
                                                                                
  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   89,385  28.3%  18,038   20.2%      12   102.7   620.4         
  TITLE WORD      31,055   9.8%   9,643   31.1%       7   397.5  2908.3         
  EXACT TITLE      2,149   0.7%   1,074   50.0%       1    50.4   477.4         
  JOURNAL         12,470   3.9%   4,277   34.3%      86  2257.3  6516.5         
  EXACT JOURNAL    4,514   1.4%   1,378   30.5%     235  1726.5  3617.9         
  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        122,143  38.6%  23,609   19.3%      29  1180.0  9287.7         
  SUBJECT WORD       758   0.2%     356   47.0%     192  4813.2 22390.2         
  SUBJECT         11,920   3.8%   5,232   43.9%     196  3057.6 11105.3         
  MAJOR SUBJECT      638   0.2%     141   22.1%     132  1453.9  3698.9         
  EXACT SUBJECT    4,077   1.3%     868   21.3%      97  1935.0 10523.4         
  MAJOR XS           604   0.2%     132   21.9%     143  1646.7  7628.2         
  EXPLODE XS       2,279   0.7%     328   14.4%     184  6994.3 22494.3         
  EXPLODE MAJOR      267   0.1%      16    6.0%     797 12162.0 32451.9         
  TREE NUMBER          7   0.0%       0    0.0%      35  7027.9 10731.2         
  MAJOR TREE NUMBER    0   0.0%       0    0.0%       0     0.0     0.0         
  DATE            10,991   3.5%   2,123   19.3%      11   243.0  1602.1         
  LANGUAGE        10,817   3.4%   1,163   10.8%      56   815.3     0.0         
  PUB TYPE         4,164   1.3%     377    9.1%      33   407.9  4240.8         
  Other indexes    7,236   2.3%   1,359   18.8%      10   256.5  4369.6         
                                                                                
  By number of indexes:                                                         
  Multiple        85,455  30.4%  19,073   22.3%      11   445.2  4736.0         
  Single         195,293  69.6%  41,740   21.4%      28  1170.3  8272.2         
                                                                                
                                                                                
  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      225   5.4%      37   16.4%       9    38.7    93.0         
  JOURNAL            637  15.3%     169   26.5%       2    20.3   104.5         
  EXACT JOURNAL      162   3.9%      44   27.2%       1    14.0    98.9         
  SUBJECT          2,973  71.4%     660   22.2%       2    24.8   262.3         
  EXACT SUBJECT      165   4.0%      48   29.1%       1     1.3     1.8         
  TREE NUMBER          2   0.0%       0    0.0%      10     9.5    12.0         
                                                                                
  By number of indexes:                                                         
  Multiple             0   0.0%       0    0.0%       0     0.0     0.0         
  Single           4,164   100%     958   23.0%       2    23.7   228.3         
                                                                                
                                                                                
  LIMITS:                                                                       
                                                                                
    Number of times limits (bit strings) used:         18,072                   
                                                                                
    Use by bit string (percentage):                                             
      Current year minus 5                               0.0%                   
      Current year minus 4                               0.0%                   
      Current year minus 3                               0.5%                   
      Current year minus 2                               0.3%                   
      Current year minus 1                               0.4%                   
      Current year                                       0.4%                   
      English Language                                  57.1%                   
      French Language                                    0.0%                   
      Japanese Language                                  0.0%                   
      German Language                                    0.0%                   
      Russian Language                                   0.0%                   
      XS Abstract                                        0.8%                   
      XS Adolescence                                     0.2%                   
      XS Adult                                           0.3%                   
      XS Aged                                            0.4%                   
      XS Animal                                          0.1%                   
      XS Case Report                                     0.0%                   
      XS Child                                           0.7%                   
      XS Comparative Studies                             0.1%                   
      XS English Abstract                                0.0%                   
      XS Female                                          0.3%                   
      XS Human                                           9.4%                   
      XS Infant                                          0.0%                   
      XS Infant, Newborn                                 0.2%                   
      XS Male                                            0.1%                   
      XS Mice                                            0.0%                   
      XS Middle Age                                      0.0%                   
      XS Rats                                            0.0%                   
      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                                         23.9%                   
      PT Journal Article                                 0.4%                   
      SUBSET AIM                                         3.7%                   
      SUBSET Indexing priority 1,2                       0.0%                   
      SUBSET Nursing journals                            0.6%                   
      SUBSET Dental journals                             0.1%                   
      SUBSET Cancer core journals                        0.0%                   
                                                                                
  BOOLEAN:                                                                      
                                                                                
    Number of searches with Booleans:                 101,718                   
      (FIND, BROWSE, SELECT, ADD-ON)                                            
                                                                                
    Percentage of ANDs                                  92.4%                   
    Percentage of ORs                                    6.5%                   
    Percentage of AND NOTs                               1.1%                   
                                                                                
                                                                                
  DISPLAY commands, by type, excluding automatic displays:                      
                                                                                
    REVIEW                                               1.3%                   
    BRIEF                                               64.0%                   
    LONG                                                 1.0%                   
    MEDLINE                                              1.3%                   
    FIELDS                                               3.4%                   
    PERIODICALS                                          0.0%                   
    BROWSE REVIEW                                        0.8%                   
    BROWSE LONG                                          0.4%                   
    BROWSE FIELDS                                        0.0%                   
    BROWSE MEDLINE                                       0.0%                   
    Other                                               27.7%                   
                                                                                
4.0  Error, EXPLAIN, HELP statistics (ASSIST & COMMAND)                         
_______________________________________________________                         
                                                                                
  Percent of commands that contained errors             10.0%                   
                                                                                
  Ten most frequent errors:                                                     
    1. NS command - no next screen                      37.1%                   
    2. First word of command is invalid                 27.6%                   
    3. FIND command with invalid index name              6.5%                   
    4. DISPLAY command contains invalid word             3.9%                   
    5. DISPLAY command - no FIND results                 2.8%                   
    6. PS command - no previous screen                   2.6%                   
    7. Valid command at an inappropriate time            1.9%                   
    8. Add-on search with invalid index name             1.9%                   
    9. Search term missing from search command           1.6%                   
   10. NS of SHOW/EXP command-no next screen             1.2%                   
   11. All others                                       13.1%                   
                                                                                
                                                                                
  Ten most frequent EXPLAIN requests:                                           
    1. BOOKS DATABASE                                   15.1%                   
    2. LOCATE (article dbs w/o monographs)              13.5%                   
    3. FIND                                              8.3%                   
    4. MEDLINE BACKFILES                                 7.0%                   
    5. COMMANDS                                          5.8%                   
    6. Unrecognized term                                 5.5%                   
    7. ADD-ON SEARCH                                     4.5%                   
    8. INDEXES                                           3.8%                   
    9. DISPLAY                                           3.8%                   
   10. MAIL                                              2.8%                   
   11. All others                                       28.8%                   
                                                                                
                                                                                
  Ten most frequent HELP situations:                                            
    1. Command mode selected from Welcome               21.1%                   
    2. First word of command is invalid                 14.8%                   
    3. FIND command with invalid index name              7.1%                   
    4. DISPLAY command-first of >1 screen                6.1%                   
    5. FIND command retrieves >1 book                    5.2%                   
    6. DISPLAY command - middle of >1 screen             5.0%                   
    7. NS command - no next screen                       3.9%                   
    8. DISPLAY command - last of >1 screen               3.3%                   
    9. DISPLAY command-complete in one screen            2.4%                   
   10. FIND command with zero results                    2.4%                   
   11. All others                                       29.9%                   
                                                                                
                                                                                
  Ten most frequent SHOW requests:                                              
    1. HISTORY                                          58.6%                   
    2. SEARCH                                           21.1%                   
    3. MAIL STATUS                                       7.4%                   
    4. SETTINGS                                          3.4%                   
    5. MEDLINE NEWS                                      2.2%                   
    6. MEDLINE GLOSSARY                                  2.1%                   
    7. MAIL SETTINGS                                     1.8%                   
    8. DISPLAY                                           0.5%                   
    9. UPDATE                                            0.5%                   
   10. DATABASES                                         0.4%                   
   11. All others                                        2.0%