How to Better Evaluate the Goodness-of-Fit of Regressions

Most of the content of this post is platform-agnostic. Since in these days I’m using Azure Machine Learning, I take it as a starting point of my studies.

It’s quite simple for an Azure Machine Learning average user to create a regression experiment, make the data flow in it and get the predicted values. It’s also easy to have some metrics to evaluate the implemented model. Once you get them, the following questions arise:

  • How can I interpret these numbers?
  • Are these metrics enough to assess the goodness-of-fit of the model?

This post wants to provide you with the statistical foundation behind these metrics and with some additional tools that will help you to better understand how the model has fitted. These tools are implemented in a R script you can simply copy&paste into an Execute R Script module.

Read the rest of the article here:

https://medium.com/wandering-in-advanced-analytics/how-to-better-evaluate-the-goodness-of-fit-of-regressions-990dbf1c0091

I use columnstore indexes on SQL 2014. What would be the advantages of upgrading to SQL 2016?

I use columnstore indexes on SQL 2014. What would be the advantages of upgrading to SQL 2016?

SQL Server 2016 really represents a drastic change for the better in regards to general performance. And the proof is that, thanks to the engine changes, this is the first SQL Server version where Microsoft actively provides a widespread increase in performance levels by simply upgrading. But what impact can it have in your daily loads if you use columnstore indexes in SQL server 2014 datawarehouse? There was already an amazing increase in performance levels with SQL Server 2014 and the columnstore indexes. Is it worth upgrading to SQL 2016? (more…)

How to bulk copy Azure ML Experiments from a Workspace to another one or do a Backup of them in Physical Files

How to bulk copy Azure ML Experiments from a Workspace to another one or do a Backup of them in Physical Files

Hi all,

today I want to tackle the issue of bulk copying more than one Azure ML experiment at once between different workspaces.

May be you already know that you can partially solve this task by copying an experiment one at a time. But you have to access to both the workspaces with your user. If not, you can simply share a workspace in this way:

https://docs.microsoft.com/en-us/azure/machine-learning/machine-learning-create-workspace

Once you can see both the workspaces in your Azure Machine Learning Studio, you can simply select an experiment and than “Copy to workspace”:

AzureML_Copy_001

and than you can choose the destination workspace:

AzureML_Copy_002

A you can imagine… you can’t simply select more than one experiment and than copy all them:

AzureML_Copy_000

Now suppose you have dozens of experiments and simply you don’t want to waste your time coping them all manually, or moreover you can’t have access to a shared workspace for security reasons. Is there a way to bulk copy your experiments? I’ll show you how to do that using few rows of PowerShell.

(more…)

Are you Ready to Use Power BI?

Are you Ready to Use Power BI?

What! NO? Get with it, my friend.  Power BI is for everyone.  All the kids are doing it… not to mention the business owners, marketers, sales campaign planners and scientists, IT Pros and common folk.  Power BI is all the rage and can be used to analyze everything under the sun – oh, and that … Continue reading

Datazen Visual Control Categories

Datazen Visual Control Categories

Choosing the right visualization control for a set of data can sometimes be challenging.  I find some aspects of designing dashboard solutions in Datazen on the surface to be very simple but it’s easy to get stuck in the details and fine points.  The purpose of this guide to help simplify and categorize visual control … Continue reading

Learn How to Use Datazen this Week

Learn How to Use Datazen this Week

SQL Server Pro Magazine is hosting my 3-part series, Designing a Mobile Dashboard Solution with Microsoft DataZen on Thursday.  The first one hour session begins at 11 AM Pacific, 3 PM Eastern Time.  There are three sessions in the series which include: Session 1: Introducing DataZen and Building a Server – 11am EDT Session 2: … Continue reading

SSAS Tabular Modeling Article Series on SQL Server Pro Magazine

I’ve just finished a series of four articles for SQL Server Pro Magazine, along with sample projects and hands-on exercises. The series will take you through SSAS Tabular model design from start to finish, using the Adventure Works sample data in SQL Server 2012 or 2014.  Follow these links to each article in the series:

Part 1 – Getting Started with SSAS Tabular
Part 2 – Easy DAX – Getting Started with Data Analysis Expressions
Part 3 – Tabular Model Administration
Part 4 – Deep Dive DAX – Solving Complex Business Problems with Data Analysis Expressions

Download the sample projects here:  Part 1, Part 2, Part 3, Part 4