Sunday, April 28, 2013

Lean Analytics: by Croll and Yoskovitz (book review)

Lean Analytics: Use Data to Build a Better Startup FasterLean Analytics: Use Data to Build a Better Startup Faster by Alistair Croll
My rating: 4 of 5 stars

Lean Analytics bills itself as how data can be used as a startup. But it really is how you use data to make and check business decisions. And it takes the discussion of key performance indicators and puts them into a context where 1. data is readily available and 2. analyzing the data is relatively easy if you knew what data to look for and what and why you are analyzing it.

The first part is fairly standard fare for metrics oriented organizations. A discussion of what data is, how to choose measures, recognizing that data is never clean. But the rest of the book starts through a range of scenarios. Different types of businesses. Different stages of business development. Different competitive environments. With the variety presented, the point is not to find the chapter that matches your situation or to pick at a description and find ways that it does not apply, the point here is that data-informed decisions have a place in a wide range of contexts. The goal with metrics is not to decide that because it is not perfect it cannot be used, the goal is to use data in a way that complements experience, instinct, and intuition in making better decisions. For that, Lean Analytics is good to read for anyone thinking about how data can be made to work, not just in internet based startups.

Disclaimer: I received an free electronic book edition of Lean Analytics through the O'Reilly Press bloggers program.

View all my reviews

Saturday, April 20, 2013

Fernando Perez: "Literate computing" and computational reproducibi...

Fernando Perez: "Literate computing" and computational reproducibi...: As "software eats the world" and we become awash in the flood of quantitative information denoted by the "Big Data" b...

I am teaching a course in logistics and supply chain.  Because the course is focused on the modeling of supply chains, and the students are generally using Excel (I actually did all of the homework solutions in Python) I used the Reinhart and Rogoff’s “Growth in a Time of Debt” discussion as a mini-case (every class I find an article to discuss.  Usually it focuses on business decisions, but this time I chose this topic.)

The focus on the class discussion was on how you look for errors.  Because Excel makes this nearly impossible, the real question was on how you focus your time.

But the real answer, as Perez mentions, it to use tools that make reproducible research simple.  The homework assignments I gave resulted in spreadsheets that covered 4 tabs and were a couple hundred columns and thousands of rows.  My solution in python was about a page of commented code which had a near one to one correspondence with the mathematical formulation of the model (with the addition of a few lines to read and massage the data.)  The spreadsheets were pretty much un-auditable.  My code had comments that would tell a reviewer what to look for.  Even for smaller problems, my students spreadsheets were fairly obtuse while my Python programs (I use Pweave) alternated between the explanation of each step with the calculations described.

The Thomas Herndon, Michael Ash, and Robert Pollin paper included R code that both demonstrated the effects of the errors of Reinhart and Rogoff.

For fun, Vincent Arel-Bundock has converted the Herndon, Ash, and Pollin into an iPython notebook, suitable for looking at (and reading) as well as downloading it and playing with the data to test any thoughts someone may have about testing the impact of various types of errors.

Saturday, April 06, 2013

Going to Fiddlesticks concert, and it was a MEOW

This was our second Fiddlesticks concert. And this time around S joined T and I. First, we got early so we could enjoy the pre-concert festivities. To celebrate Fiddlestick's birthday, T decorated a birthday party hat.
Here is the hat I made.  It has a dinosaur.
Next was learning the songs for the concert. The Pittsburgh Children’s Festival Chorus was performing some of the singalong songs along with some movements. The first time T sees anything he does not really react but is very intent so we never know what he is understanding
The Children's Festival Chorus at the Fiddlesticks pre-concert
Leading up to the start of the concert we brought T up the concert hall. He loved the view from the balcony where he could see everything going on. The instruments, the performers coming on stage, the audience filing in.
What instrument is that on the stage?
But (surprisingly enough) it was the music that took first place for T. Since the theme was Fiddlestick's 20th birthday, the theme was cats (Fiddlesticks is a cat). So the first song was The Waltzing Cat by Anderson and Ms. Williams cued the audience on when the 'meow' came up so the kids could join in. Then the Cat Duet by Rossini was performed featuring Ms. Williams and Ms. Maloney. By this point T was very happy, enjoying the music, the silliness presented on stage, and generally responding to the music. When we got home, it was clear that he remembered everything. We found a video of a performance of the Cat Duet that we played in the background while eating lunch. And if we were wondering about his remembering the concert, we found that he remembered the Fiddlesticks Theme Song dance. Clearly, he spent the sing-a-long session committing it to memory. A thoroughly fun time. And something that we will do again someday. [Preconcert thoughts at the Pittsburgh Symphony Blog]

Thursday, April 04, 2013

Let's go sing Happy Birthday to Fiddlesticks! at the Pittsburgh Symphony Orchestra

[This is also at the Pittsburgh Symphony Orchestra Blog Site] It's Fiddlesticks' birthday! And we are going to a concert! This coming Saturday will be the second time we have gone to one of the PSO Fiddlesticks' Family concert. The first time we did not know what to expect. But now that we do, we'll be ready to enjoy it. Fiddlesticks Happy Birthday Concert

For both of us, music had become a part of our lives, something that we can share and we wanted our now two year old son to do so too. But the question we had was what did that meant. We've seen the fads that listening to music would make a child smarter but we did not want any part of that. Because we were also not interested in a passive child. As we have exposed him to music in our lives, he has listened to my wife's playing the piano, watched videos with music in the background and of performances, and yes, even some videos aimed at toddlers that included classical music. But he does not just listen and watch. we are thoroughly entertained by his response to the music. In the ways of a two year old with limited oral skills and coordination, he sometimes just listens, sometimes he sings along, sometimes he pretends like he is conducting the piece, and sometimes he tries to dance ballet, sometimes hip-hop, and sometimes just jumping and moving to the rhythm.

Talking about a Bass

We've brought him to concerts, recitals, and performances and appreciate the venues where you are not just a spectator, but you can react and respond to music as you experience it. And that is what I most enjoy about Fiddlesticks. The relatively modern traditions of being quiet and not responding to a performance are put aside, and we can react to what we see. We enjoy the performers interacting with the kids sharing their joy of playing.

PSO viola working the crowd before Fiddlesticks

And this is what we want our son to experience as he grows. Not a world where he is a spectator, but a world where he takes in the environment and responds to it. And someday, create something to add to this environment.

Clapping for the PSO

Monday, April 01, 2013

Parenting 29 months: Playing around

Playing with Marble Run by LugerLA
Playing with Marble Run, a photo by LugerLA on Flickr.
This month was one of learning about playing. He loves the marble run toy. The learning development people say it is because he can handle the fine motor skills involved and there are lots of movements that are consequences. At this point, we build it and he just makes the marbles go around. But we figure that this has a long lifetime since someday he will learn how to build designs as well.  Legos and trains are the same way, he likes to play with them, but does not yet have the coordination to design.  But he is starting to have some creativity in design.  We have another puzzle game that he has figured out his own way to play.  He calls it choo-choo, because he likes to line up like pieces in a row, like a train.

I think that this is how to do this puzzle.
 The other task has been trying to maintain his chinese with his grandparents gone. TV actually helps here. Sesame Street has a series of shorts called "Fun Fun Elmo" which is aimed at Chinese-american kids in Brooklin and Queens, NY. Pocoyo has a Chinese translation (including a narrator whose day job is as a comic). And there are a number of CCTV videos available on YouTube as well. Fun Fun Elmo actually is doing a reasonable job. We (well, S) has noticed that his pronunciation of words in the show is improving. And through repetition he can actually recognize a few characters.
More recently, he has started to become more sociable. Latest report from day care reports him causing trouble along with another boy in the class (a drinking game no less). So that is a change from him finding his own corner to play in. Probably a good thing. And the attention span has seemed to return, so we can get him to sit and read along for a couple books at a time. All in all a good month.