MATLAB: Norm form and prediction

Deep Learning Toolboxnnstartnntoolnormalize

hi
i want to use ann for forecasting water table
i have two set of data. water table from past and temperature.
it means two matrix with 12 column and 15 row
12 column means 12 month
and each row are separated data from a year(15 year).
it mean i have two data for month and year
i devided my data into 2 matrix
first 11 year for input and 4 year for output
i want to use nntool to forecast and predict water table for future years with under consideration of temperature. now my questions:
  1. some of my data don't have value and matlab give them 0 in my table. is this affect the network? and if it is what should i do?
  2. do i need to normalize my data before using nntool and how?
  3. when i start nnstart, do i need to use time series?
  4. how i consider the effect of temperature?
sorry for my long question. I am new in matlab and have a lot of question. thanks a lot.

Best Answer

I would unfold your data into a single 2 dimensional input time series matrix of size
[ 2 180 ] = size(series)
where the inputs are waterlevel and temperature.
The target is just the future waterlevel.
To estimate how far into the future you can predict, obtain the autocorrelation function of waterlevel and crosscorrelation function of waterlevel and temperature.
From the correlation functions you can determine the significant lags of the local correlation peaks.
Then use a subset of the significant lags in a narxnet.
Hope this helps.
Thank you for formally accepting my answer
Greg