We assume that you have chosen to start the Wizard (figure 1). The Wizard is also available from the File menu. The Wizard guides you during the process of creating a new experiment. You start by selecting a template experiment from a list. This template serves as a kind of skeleton for your experiment.
Experiments in YALE are made up from a set of nested operators. An operator consumes a set of input objects and produces some output objects. These objects can be data files, models, performance criteria, and more. Simple operators like a learner consumes an example set and produces a model that can be used by an applier for prediction. Moreover, some operators can have inner operators.For Example, a k-fold cross-validation splits up an example set into training set and test set and applies its inner operators which are a learner and an applier. Each time a disjoint test set is used.
If you click on the radio button next to the cross validation template, the structure of the sample experiment is depicted on the right. You see an operator chain consisting of an ExampleSource that reads data from a file. This data is then passed to the cross-validation which itself has inner operators, in this case learner and applier for a support vector machine (SVM). See the YALE Tutorial for more information on SVMs and the individual operators.
Now that you have chosen the template, click on next. In this step you can enter some of the most important parameters (figure 2). In case of a cross-validation this is e.g. the number of validations.
A lot of Experiments in YALE need a data file as input which is known in supervised learning as an exampleset. The examplesets have to be in a special format and requires that the attributes are described in a seperate XML file. In other words the file in special format is the set of examples where each example is a vector and the XML file describes the semantics of every value in the vector.
In order to create such an XML file now you can press the small Edit button next to an attribute description file property. The dialog popping up is described in section 2.6 and is called Attribute Editor. The files generated with help of the Attribute Editor can also be used as input for the ExampleSource operator, which is the standard data input operator for YALE.