CMOS inverter operation with resistors connected

[hast]

Hi all, I would like to ask which is the main reason of connecting the resistors directly to the output and not as I point out in the picture? Is there any benefit in terms of speed or noise performance? Could you provide some material regarding the analysis of this inverter?

 

[barry]

If you were to put the resistors in the source, Vgs would vary with the load.