Data Science: Visual Programming using Orange Tool
What is Visual Programming?
It is a type of programming language which anyone can understand. Anyone can describe the process using illustrations. In text-programming language, a programmer things like a computer whereas in visual programming, programmer describes process which makes sense to a human being.
Implementation
First, we use the File widget in the canvas and load the inbuilt zoo dataset in the workflow. You can also import your own dataset using browsing or using url. This datset is of type classification and have 16 attirubtes & 101 data instances.
Now we have to send this data as an input to the Data Sampler. Data Sampler selects a subset of data instances from an input data set.
It outputs a sampled and a complementary data set. The output is processed after the input data set is provided and Sample Data is pressed.
I have kept 75% of data for training & rest for testing. It is suggested to keep training dataset between 70–90 percent.
Now, we need to send this sample data from Data Sampler to Test and Score. The widget tests learning algorithms. Different sampling schemes are available, including using separate test data.
Also, connect machine learning models to Test and Score widget. I have used 3 — Neural Network, Logistic Regression, SVM algorithms for my demonstration. These 3 algorithms are most suitable for classification.
Here, Data Sampler widget passes 75% of data for training and rest 30% for testing to Test and Score widget.
Now get the comparison scores of the three different algorithms by testing on the train data. To do so double click on the Test and Score widget and choose the option of Test on train data there and get the scores for all three algorithms.
To test the learning algorithms on the basis of the test data choose the option of Test on test data in the Test and Score widget.
So till now we have compared 3 different machine learning algorithms for classification dataset. Using orange tool, analysis become a lot simpler and easy to carry out.