Regression and Classifications are two major area in Classification Technique in Data Mining.
Toady I heared a question what is regression and what is classification and where am i use which condition.
The Image says lots of word than I write.
The key point is if you have large data and you want to :
- Find the Catagories of that You shoud follow the path via classification.
- You want to know the quantity you have to follow the path from regression.
Classification : Is the task when the dicrete output y consist of one or more dicrete varaibles.
Let’s consider a input vector X1,X2,X3,…….. Xn and output vector varaible Y respresenting the class varaibles Y1,Y2,Y3,…..Yn, Where n is the number of training sample.
Training is the process of finding the values for adjustable parameter w of the mapping function f on basis of the dataset. That dataset is refered as training set.
Testing preformance of a classifier is known as generalisation.
If training performance > testing performance is called overfit.
One way to reduce the overfit is divide the training data into training & validation subsets.
A well known training testing protocol for this is n-fold cross validation.