huangyhg

data selection and modelling.
hi,
i have a large quantity of data from a test site where 500 parameters are measured every minute and i have acces to 2 years of this data. i want to model 5 of these parameters in function of the most important other parameters fff">(the model has 5 output parameters and i want to select the best parameters to model these 5 output parameters). the data set is noisy, clouded and some parameters are redundant. i am looking for a method to determine the parameters which are higly correlated with the 5 parameters i have to model. i know i can just calculate the correlation coeficcients. but i dont think this is suffucient.
i have examined a method called principal component analysis but i dont think there is a way to calculate principal components in function of the 5 parameters i wish to model. here comes my first question, is there a method wich calculates principal components in function of other parameters?
i am currently examining feature selectionfff"> but i don't find good references about this method. can someone give advice on this method?
if you have any other method to calculate the best variables to model with in function of the output parameters.
thanks in advance, regards
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try a designed experiment to determine which parameters and interactions directly affect performance. from there, you should be able to simplify your data mining.
regards,
thank you for your reply.
but i am not allowed to perform experiments on the site. i have to do it with the data i can acces. i also don't think that the site allows such controlled experiments since it is constantly in industrial application.
kind regards,
it doesn't mean you have to experiment on site. you select a portion of data where one variable is holding constant, then a second set where a different variable is constant. you can then perform data regressions to see how the variables interact and if an equation.
the problem is trying to pare it down. the best way is to plot several variables and visually see which ones appear to matches first. somethings can be deduced from principles, like reactions speed up with temperatur in a power function. heat transfer is proportional to delta t.
generally its called "design of experiments" under advanced statistical process controls tools, google that to find articles.
thank you for clarifying my posting intent dcasto.
regards,
thank you for your answers. i'll look things up and let you know if it worked!
thank you very much! regards
factor analysis with two factors can determine best variables compatible with your 5 vars. draw a 2-d graph of the two factors to visually confirm close association of variables.

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