"... In PAGE 3: ... 4.1 Query Locality Table1 shows query locality statistics for the THOMAS and Excite logs. We collect the average number of queries, distinct queries, topics, singleton topics, topics occurring multiple times, and topics that contain multiple distinct queries.... In PAGE 4: ...3% Table 2: Query and Topic Locality over time in THOMAS a function of the number of top topics or distinct queries, respectively. Table1 (a) shows the average for THOMAS over the full 40 day logs. The average number of matching queries from our test database is in parentheses in columns 1 and 2.... ..."

"... In PAGE 3: ... 4.1 Query Locality Table1 shows query locality statistics for the THOMAS and Excite logs. We collect the average number of queries, distinct queries, topics, singleton topics, topics occurring multiple times, and topics that contain multiple distinct queries.... In PAGE 4: ...3% Table 2: Query and Topic Locality over time in THOMAS a function of the number of top topics or distinct queries, respectively. Table1 (a) shows the average for THOMAS over the full 40 day logs. The average number of matching queries from our test database is in parentheses in columns 1 and 2.... ..."

"... In PAGE 3: ... Many of the same queries are repeated many times. Table1 shows some of the more popular queries with a count of the number of times they were entered. Of the 94,911 separate queries recorded, only 25,321 were unique.... In PAGE 3: ... The fact that88 percent of allqueries contain 3 or fewer words suggests that most queries in this application consist of a single concept expressed as a word or phrase. An examination of the searches most frequently submitted, shown in Table1 , tends to confirm thishypothesis. Although a number of studies have been done on the types of queries submitted to information services [9], there is not a large amount of data on what happens in systems with free-form or natural language quot; queries.... ..."

"... In PAGE 3: ... Many of the same queries are repeated many times. Table1 shows some of the more popular queries with a count of the number of times they were entered. Of the 94,911 separate queries recorded, only 25,321 were unique.... In PAGE 3: ... The fact that 88 percent of all queries contain 3 or fewer words suggests that most queries in this application consist of a single concept expressed as a word or phrase. An examination of the searches most frequently submitted, shown in Table1 , tends to confirm thishypothesis. Although a number of studies have been done on the types of queries submitted to information services [9], there is not a large amount of data on what happens in systems with free-form or natural language quot; queries.... ..."

"... In PAGE 3: ... This result improves even more if further related training text is available. For example, the collection of writings by Thomas Je erson shown in Table5 is now available in the public domain. The addition of this collection to the training text improves the estimate down to 1.... ..."

"... In PAGE 3: ... This result improves even more if further related training text is available. For example, the collection of writings by Thomas Jen0berson shown in Table5 is now available in the public domain. The addition of this collection to the training text improves the estimate down to 1.... ..."

"... In PAGE 4: ...2 Locality as a Function of Time We examine locality as a function of time (days and weeks) in the THOMAS logs. Table2 shows that for days between 7/15 and 9/11, the percent of queries that match a top topic or distinct query on a previous day or week. Columns 2 through 4, columns 5 through 7, and columns 8 through 10 list the percentage of queries that match one of the top a20 top- ics or top a20 distinct queries on the previous day with daily... In PAGE 5: ... 4.4 When to Build or Update a Replica Query locality decreases very gradually with time in our logs, as illustrated in Table2 . Even in the dynamic envi- ronment of the Web, search engines routinely return URLs a few month old [21] which implies daily updates are not nec- essary.... ..."