ubuntu 12.04 and ROS Fuerte

Hi,

This is given in the website:

~occthresh (float, default: 0.25) Threshold on gmapping's occupancy values. Cells with greater occupancy are considered occupied (i.e., set to 100 in the resulting sensormsgs/LaserScan). New in 1.1.0.

It says that the default value is 0.25 and again set to 100...for LaserScan.

1.Can any one explain how the intuition behind setting this parameter?

2.What is the min value and maximum value for occ_thresh parameter?

3.What should this value be if one is using a hokuyo laser ?

4.Will this change for every sensor ? If yes, what should the value be for Kinect ?

Thanks, Sai