Different accurency of the training data-how to handle it?

[Doro07]

Hey,
I'm despratly needing help with one issue:
But I'm currently using this Toolbox for my masterthesis. The task of my masterthesis is to compare different accurate CO2 sensors for the ocean. Therefor I should creat a neural network and should find out which one is providing more accurate results. The idea is, that one sensor is less expensiv but has an accurancy of +- 5µatm and the other one is more expensiv and works with an accurancy of +-2µatm. I should now determine, if the neural network provids better results when I train it with the double the amount of unaccurate data. My biggest problem is, that I don't know where I can tell the neural network the accurancy of the data that it use to be trained. Maybe someone here knows a function which I need to use to tell MatLab about the accurancy of the Training data. If you know something to help me I would be very very glad!
I hope you understand my problem and can help me.