Biasing

I am doing some biasing using the weight window (with command WW-FACTOr). But I have done a test without biasing and I get the same result! Why?

Check that you have in input a WW-THRESh card. It is compulsory when using WW-FACTOr, otherwise the two energy thresholds are set equal to zero, and it is as if the weight window was not there.

When simulating electromagnetic showers of high energy, it takes very long time. Which biasing should I use to increase performance?

If you are not interested in fluctuations or correlations, use Leading Particle Biasing (see EMF-BIAS on the Manual). For shielding calculations of high energy accelerators, the use of this biasing feature is very effective.

I am interested in a correlated analysis on a event by event basis. Is there anything which I must define in the input for that purpose?

You must define a "fully analogue" simulation with WHAT(2)<0.0 in the GLOBAL card.