Re: MultipleLinearRegression - Strange results

2015-06-04 Thread Mikio Braun
For linear regression, the main tasks are computing the covariance matrix and X * y, which can both be parallelized well, and then you need to solve a linear equation whose dimension consists of the number of features. So if number of features is small, it actually makes sense to do the setup in Fl

Re: MultipleLinearRegression - Strange results

2015-06-04 Thread Till Rohrmann
I agree that given a small data set it's probably better to solve the linear regression problem directly. However, I'm not so sure how well this performs if the data gets really big (more in terms of number of data points). But maybe we can find something like a sweet spot when to switch between bo

Re: MultipleLinearRegression - Strange results

2015-06-04 Thread Ted Dunning
> >> > >> > >> On Wed, Jun 3, 2015 at 8:05 PM, Mikio Braun > >> wrote: > >> > >> > We should probably look into this nevertheless. Requiring full grid > >> search > >> > for a simple algorithm like mlr sounds like overkill

Re: MultipleLinearRegression - Strange results

2015-06-04 Thread Ted Dunning
On Thu, Jun 4, 2015 at 1:26 PM, Till Rohrmann wrote: > Maybe also the default learning rate of 0.1 is set too high. > Could be. But grid search on learning rate is pretty standard practice. Running multiple learning engines at the same time with different learning rates is pretty plausible. Al

Re: MultipleLinearRegression - Strange results

2015-06-04 Thread Mikio Braun
simple algorithm like mlr sounds like overkill. >> > >> > Do you have written down the math of your implementation somewhere? >> > >> > -M >> > >> > - Ursprüngliche Nachricht - >> > Von: "Till Rohrmann" >> > Ge

Re: MultipleLinearRegression - Strange results

2015-06-04 Thread Till Rohrmann
> > > -M > > > > - Ursprüngliche Nachricht ----- > > Von: "Till Rohrmann" > > Gesendet: ‎02.‎06.‎2015 11:31 > > An: "dev@flink.apache.org" > > Betreff: Re: MultipleLinearRegression - Strange results > > > > Great to hear. Th

Re: MultipleLinearRegression - Strange results

2015-06-03 Thread Ted Dunning
1 > An: "dev@flink.apache.org" > Betreff: Re: MultipleLinearRegression - Strange results > > Great to hear. This should no longer be a pain point once we support proper > cross validation. > > On Tue, Jun 2, 2015 at 11:11 AM, Felix Neutatz > wrote: > > >

AW: MultipleLinearRegression - Strange results

2015-06-03 Thread Mikio Braun
5 11:31 An: "dev@flink.apache.org" Betreff: Re: MultipleLinearRegression - Strange results Great to hear. This should no longer be a pain point once we support proper cross validation. On Tue, Jun 2, 2015 at 11:11 AM, Felix Neutatz wrote: > Yes, grid search solved the problem :) >

Re: MultipleLinearRegression - Strange results

2015-06-02 Thread Till Rohrmann
Great to hear. This should no longer be a pain point once we support proper cross validation. On Tue, Jun 2, 2015 at 11:11 AM, Felix Neutatz wrote: > Yes, grid search solved the problem :) > > 2015-06-02 11:07 GMT+02:00 Till Rohrmann : > > > The SGD algorithm adapts the learning rate accordingly

Re: MultipleLinearRegression - Strange results

2015-06-02 Thread Felix Neutatz
Yes, grid search solved the problem :) 2015-06-02 11:07 GMT+02:00 Till Rohrmann : > The SGD algorithm adapts the learning rate accordingly. However, this does > not help if you choose the initial learning rate too large because then you > calculate a weight vector in the first iterations from whi

Re: MultipleLinearRegression - Strange results

2015-06-02 Thread Till Rohrmann
The SGD algorithm adapts the learning rate accordingly. However, this does not help if you choose the initial learning rate too large because then you calculate a weight vector in the first iterations from which it takes really long to recover. Cheer, Till On Mon, Jun 1, 2015 at 7:15 PM, Sachin G

Re: MultipleLinearRegression - Strange results

2015-06-01 Thread Sachin Goel
You can set the learning rate to be 1/sqrt(iteration number). This usually works. Regards Sachin Goel On Mon, Jun 1, 2015 at 9:09 PM, Alexander Alexandrov < alexander.s.alexand...@gmail.com> wrote: > I've seen some work on adaptive learning rates in the past days. > > Maybe we can think about ex

Re: MultipleLinearRegression - Strange results

2015-06-01 Thread Alexander Alexandrov
I've seen some work on adaptive learning rates in the past days. Maybe we can think about extending the base algorithm and comparing the use case setting for the IMPRO-3 project. @Felix you can discuss this with the others on Wednesday, Manu will be also there and can give some feedback, I'll try

Re: MultipleLinearRegression - Strange results

2015-06-01 Thread Till Rohrmann
Since MLR uses stochastic gradient descent, you probably have to configure the step size right. SGD is very sensitive to the right step size choice. If the step size is too high, then the SGD algorithm does not converge. You can find the parameter description here [1]. Cheers, Till [1] http://ci.

MultipleLinearRegression - Strange results

2015-06-01 Thread Felix Neutatz
Hi, I want to use MultipleLinearRegression, but I got really strange results. So I tested it with the housing price dataset: http://archive.ics.uci.edu/ml/machine-learning-databases/housing/housing.data And here I get negative house prices - even when I use the training set as dataset: LabeledVec