neural network using R (neural net package) : <p>I want to forecast sales of retail companies. 
I am using the neural net package neural net. </p>

<p>My code:</p>

<pre><code>    nn &lt;- neuralnet(f,data=train_,hidden=c(14,12,4),linear.output=F,threshold = 0.01,
        stepmax = 1e+08, rep = 10, startweights = NULL,learningrate.limit = NULL,
        learningrate.factor = list(minus = 0.6, plus = 1.15),
        learningrate=NULL, lifesign = "none",
    algorithm = "rprop+", err.fct = "sse", act.fct = "logistic", 
exclude = NULL,constant.weights = NULL, likelihood = FALSE)
</code></pre>

<p>My model is not even as good as a linear regression. 
What can I do to improve accuracy of the model ??</p>

<p>Data: 2'300 Quaters (for e.g. Q1 2003) and 18 variables (for e.g. inventories) </p>
