In my last post I built a regression model with a single predictor variable. That variable represented the value of a single pixel from a 28×28 image of a hand written digit. In this post I will look at some model variations based on using a larger number of input variables.
Logistic Regression pt.1
In a recent post I created a table that contained two classes of data: images that represent either the handwritten digit ‘5’ or the digit ‘6’. In this post I’ll model the data using logistic regression. I will also take the opportunity to look at the role of training and test datasets, and to highlight the distinction between testing and validation.
The Power of Journals
If you have ever been to a JMP Discovery Summit or perhaps a JMP user group meeting you will no doubt have come across journal files. The first time you create one can be an unnerving experience since a new journal is simply a blank window. But that is their beauty: they are a blank canvass onto which you can save your JMP output. But more importantly they are a place to capture your thoughts.
Scripting Data Filters
A question that I’ve been asked a few times is “how can I script a data filter?”. My response to this question is always the same: “why would you want to do this?”.
In scripting, a common task is to manipulate data through row selections; a data filter is a tool that allows you to perform the same task interactively without scripting. Which means: you either script or you use a data filter.
So now the question becomes: “how can I implement functionality equivalent to a data filter using JSL?”.
In this post I will look at answering this question. But since there are occasions where is is desirable to explicitly script the data filter, I’ll look at that too!
Fives and Sixes
In my last post I was able to successfully re-orient a set of pixel data to reconstruct images of handwritten digits. SInce version 12 of JMP we have been able to create expression table columns that can contain images. That’s a logical location to store my newly revealed images:
Flippin’ Images
My last post contained a picture of a window that contained a grid of images. This was a randomly generated array of images based on an extract from the MNIST dataset. This database contains over 60,000 samples of handwritten digits.
However, my pixel data was disoriented and the images looked more like hieroglyphs. Fortunately JMP understands an image as an ‘object’, and allows a variety of transformations to be applied to it, including flipping and rotating.
Hieroglyphics?
What is this? Any guesses?
(to be continued… )
Scripting Table Subsets
The best way to script table manipulation tasks such as joins and subsets is to first perform the task interactively and then make a copy of the source JSL that is automatically generated by JMP. In many instances this code is sufficient, but sometimes you need to make the code more general, and that’s where things can get tricky.
In this post I will take you through the process of transforming the JMP-generated code into a more flexible piece of JSL.
Lists – By Example
14 things you can do with lists.
Top 6 Blog Posts
The top 6 visited posts of 2016 were all written in 2015!
Here is the list: