Hi,
I hope that you have your bachelors degree already . Anyways, I've contacted Esri support to ask about parameters used when using IDW interpolation in LAS dataset to raster function. They answered as followes: "When we utilize the IDW Cell Assignment type under binning there is not a search radius applied, and the power used is 1. The reason that a search radius is not applied is due to the fact that with the binning option, only the points within each cell are used to determine the cell value in the output raster.
However, if your customer is using the LAS Dataset to Raster tool to generate a DSM or DTM, I would suggest that they utilize Triangulation with Natural Neighbor as the Interpolation method. The Triangulation interpolation methods derive cell values using a TIN based approach while also offering the opportunity to speed up processing time by thinning the sampling of LAS data using the Window Size technique."
If you by any chance know other way to use IDW interpolation when converting LAS data to raster without using vector representation of LAS data (by this I mean using LAS to multipoint and IDW functions), I will be very grateful for any suggestions.