advancedAPI.md

Advanced Options:

If you've done ML before, machineJS is incredibly useful in that it already puts in place most of the structure for all the parts of the process you have to repeat each time.

As much as possible, we've tried to avoid hardcoding in values, instead allowing the user to pass in values, or setting default values if the user doesn't pass in any arguments.

To get the best idea of all the options available to you, please check out processArgs.js, where we set many of the default values that you'd want to modify. In the meantime, here are some of the more widely used options.

• --alreadyFormatted: A boolean value 'true' or 'false', noting if your data has already been formatted. Useful if you're just tweaking parameters and don't want to repeat the oftentimes time-expensive data formatting process again. If you pass in this flag, make sure your files are included in the pySetup/testingFileNames.js json list. I've included a couple of examples. You can get the fileNames from pySetup/utils.js, inside of the formatData function. Just copy paste the fileNames obj data-formatter gives to the callback, into the testingFileNames.js file, giving it a property of whatever the 'outputFileName' property is. You should be able to pick up the pattern pretty easily :)
• --join: a path to a data file that will be joined in with your training and testing data, in the same way you'd join SQL tables.
• --predict: see above (Format of Prediction File).
• --dev: This flag indicates that you are doing engineering work on machineJS itself. It does things like: a) set the number of rounds to a third of what it normally is b) assume we already have data formatted c) if no data is passed in, automatically use the kaggleGiveCredit.csv dataset
• --devKaggle: Does all the same things as --dev, but also runs --predict on the default dataset kaggleGiveCreditTest.csv
• --devEnsemble: Assumes that we already have predictions made for us by the rest of the module and present in predictions/*.csv. Allows you to focus on assembling your ensemble without having to retrain the models each time :)
• --dfOutputFolder: if, for some reason, you want the results of data-formatter written to a different directory. We use this for the test suite, but it probably isn't useful for much other than that.
• --ensemblerOutputFolder: much like the dfOutputFolder option above, you can choose to overwrite the default location for the output results. Used in our test suite, but probably not useful for many other cases.
• --bestClassifiersFolder: much like the dfOutputFolder option above, you can choose to overwrite the default location for the bestClassifier. Used in our test suite, but probably not useful for many other cases.

Validation Splits

The ensembler module, which uses machine learning to aggregate together all the results of each trained algorithm, will always benefit from more information, and thus, more trained algorithms.

To support this, we are using a consistent valdiation data split for a given test.csv dataset. This means you can change your training.csv data (new feature engineering, new ways of normalizing the data, etc.), but still use the predictions from previous training data sets. The only stipulation is that the rows must be in the same order. What you put into each row is entirely up to you!

If you ever want to ask machineJS to create a new validation split for you, simply delete the *validationData.npz files from the data-formatterResults directory.