Calculating Statistics on DR$ tables

I have several DR$ tables in my database. I think they come because I am using text indexes. This is third party application. When I run dbms_stats to do statistics on entire schema, it never calculates statistics on DR$ tables. Somewhere I had read that Oracle uses rule base optimizer , yes rule based optimizer for these tables. I am on Oracle 10.2.0.4. When I rebuild text indexes, it never computes statistics on these tables as well.
What is stage that some of my queries involving text indexes run slow that database control (database tuning advisor) is recommending run statistics on these tables!!! Can someone provide their thoughts on it?
You may want to review 'Performance Tuning' chapter in the Text Application Developer's Guide.
http://docs.oracle.com/cd/B12037_01/text.101/b10729/aoptim.htm
It discusses those tables and how to optimize the stats.
It will also tell you this:
7.1.1 Collecting Statistics
By default, Oracle Text uses the cost-based optimizer to determine the best execution plan for a query. To allow the optimizer to better estimate costs, you can calculate the statistics on the table you query. To do so, issue the following statement:
ANALYZE TABLE <table_name> COMPUTE STATISTICS;
Did you note that is says 'cost-based optimizer'?
As for those DR$ tables:
7.7.7 What tables are involved in queries?
Answer: All queries look at the index token table. Its name has the form DR$indexname$I. This contains the list of tokens (column TOKEN_TEXT) and the information about the row and word positions where the token occurs (column TOKEN_INFO).
The row information is stored as internal DOCID values. These must be translated into external ROWID values. The table used for this depends on the type of lookup: For functional lookups, the $K table, DR$indexname$K, is used. This is a simple Index Organized Table (IOT) which contains a row for each DOCID/ROWID pair.
For indexed lookups, the $R table, DR$indexname$R, is used. This holds the complete list of ROWIDs in a BLOB column.
Hence we can easily find out whether a functional or indexed lookup is being used by examining a SQL trace, and looking for the $K or $R tables.

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