The accuracy of the results in Data Mining Viewer

In doing the Exercise 6 in the 70-448 self-paced training kit (p.391), I found that my results in the Data Mining Viewer in step 2 and step 3 (with total children instead of age) are different from the book sample. Later, I realize my case sample has a different composition from the book (p.383): 6536 vs. 6403, comparing with 6509 vs. 6430 in the book. Since I did not change the vTargetMail data, I suspect these differences come from the 70% random sampling in creating the mining structure model. Now the issue is: If the results are affected by the random sampling for the training process, how reliable of the model results?

Fatal Internal Error on the Analysis Server Properties dialogbox - restart the SSAS

If you tried to change the four QueryLog values on the Analysis Server Properties dialogbox and a Fatal Internal Error when clicking OK to save the changes. Just click 'Reset default' and restart the SSAS. Then you can change the property values.

"Access is denied" on msmdsrv.ini

Today, I try to see the feature settings in msmdsrv.ini file in the OLAP\Config folder. However, I get an "Access is denied" message. The login ID has the admin right. Under the folder, there are msmdsrv.ini and msmdsrv.bak files (do not know when the system created the .bak file and why). The .bak file is newer than the .ini file. Finally, I moved the .ini to somewhere else and renamed the .bak file to .ini file. The problem is solved.