Merge pull request lisa-lab#34 from herr-biber/master

Fix typo.

Author: nouiz

doc/rbm.txt

@@ -573,7 +573,7 @@ chain to get the free energy of the negative phase. Note that the
 ``chain_end`` is a symbolical Theano variable expressed in terms of the model
 parameters, and if we would apply ``T.grad`` naively, the function will
 try to go through the Gibbs chain to get the gradients. This is not what we
-want (it will mess up our gradients) and therefire we need to indicate to
+want (it will mess up our gradients) and therefore we need to indicate to
 ``T.grad`` that ``chain_end`` is a constant. We do this by using the argument
 ``consider_constant`` of ``T.grad``.
 
@@ -651,7 +651,7 @@ all bits are independent. Therefore,
 
 Here :math:`x_{-i}` denotes the set of all bits of :math:`x` except bit
 :math:`i`. The log-PL is therefore the sum of the log-probabilities of each
-bit :math:`x_i`, conditionned on the state of all other bits. For MNIST, this
+bit :math:`x_i`, conditioned on the state of all other bits. For MNIST, this
 would involve summing over the 784 input dimensions, which remains rather
 expensive. For this reason, we use the following stochastic approximation to
 log-PL: