Thursday, June 18, 2015

Applied Predictive Modeling By Kuhn and Johnson: Book Review

Applied Predictive ModelingApplied Predictive Modeling by Max Kuhn
My rating: 5 of 5 stars

I regard this as a more applied counterpart to more methodology oriented resources like Elements of Statistical Learning. So it applies machine learning methods that are found in readily available R libraries. In addition, the author is also the lead on the caret package in R, which provides a consistent interface between a large number of the common machine learning packages.

1. Built around case studies that are woven through the text. For each chapter, the math/stats is developed first, then the computational example is at the end, so that the example can develop data manipulation, application of method, then model evaluation. I like this as it allows for more complex and messy data sets than when using a new, small example for each problem. Also allows for better discussions when illustrating the differences between methods.
2. Data manipulation/data processing is given a separate chapter early on. I appreciate the attention given to working with the data (e.g. missing value imputation). There are other resources in data handling, but not in the same place as those that address the statistics methodology.
3. Emphasis on model evaluation. There is an early chapter devoted to model evaluation. Then each major section of the book has an early chapter devoted to model evaluation of that class of problem. This is in contrast to many books that are built around types of algorithms, and model evaluation is fit in. Methods and algorithms are relatively easy compared to the thought process of determining what is the right thing to do. It figures that this book will be strong in model evaluation when one of the authors is the lead on the caret package in R.

I used this as a supplement in teaching a data science course that I use a range of different resources because I need to cover working with data, model evaluation, and machine learning methods. The next time I teach this course, I will use only this book because it covers all of these aspects of the field.

View all my reviews

Monday, June 01, 2015

There are pirates at Fiddlesticks!

Fiddlesticks Pittsburgh Symphony Summer Escape Concert

Today's Fiddlestick's concert theme was summer vacations, and as we had recently taken one we were all prepped for this concert. So we very much enjoyed having the thread and mini-story of finding a vacation story for Fiddlesticks.  And as my son is getting older, he appreciates more aspects of this. 

Now that my son is old enough to be learning to play piano himself, we are more like the intended audience of the Fiddlesticks concerts.  So what do we want to see.

1.  The experience of hearing a symphony live, in concert, in a venue with the right proportions, which sounds richer and with more layers than anything that can be played on home speakers.
2.  A sense that music can exist in a context and communicates something.
3.  An experience in a place where responding to music is acceptable.

Fiddlesticks Pittsburgh Symphony Summer Escape Concert
Making a pirate ship

Certainly, the discovery time activities are meant to put the kids at ease. We watched and listened to the contra bassoon and heard a talk and got an autograph from an oboist.  We sang with Katy Williams to Bippity-Boppity-Boo and the Fiddlesticks song. We made a pirate ship and sailed it in the outside fountain. All of this was to make the kids comfortable.

Fiddlesticks Pittsburgh Symphony Summer Escape Concert
Sailing in the courtyard fountain

The activities in large part are making what is obviously adult space (Heinz Hall) into a place where kids have the freedom to explore, play, and interact with things musical, or even peripherally related to music. So making a pirate ship and sailing it in the fountain is related to a sing-a-long at the piano and watching and listening to symphony musicians playing in the lobby. And by the time they get to the hall, the kids and adults are comfortable with the setting.

In the concert itself, the sense is that music is meant to be responded to. Whether it is Katy, Fawzi, or Fiddlesticks running around on-stage or the symphony playing a piece, unlike a normal PSO concert, there is no need to try to stop a child (or adult for that matter) to express amusement, recognition, joy, or empathy in the moment. When an audience member reacts, we can acknowledge the reaction instead of trying to contain it. and it makes for a different experience (I noted that there were a number of adults in the audience without any obviously attached children, so this may go beyond kids.)

My son enjoyed the experience. I spent the concert watching his expressions change as the pieces developed and listening to his observations. Then the story he told my wife about the concert when we got back. We enjoy having music part of our lives, and want our kids to share the wonder and delight in listening and creating music themselves as they grow up,  And Fiddlesticks is a part of that.

Sunday, May 31, 2015

Parenting month 55: ability vs. effort

Reading Dr Seuss for his baby sister
Reading Dr. Seuss for his little sister
In addition to our little Mexican vacation, this month saw A (12 months) becoming much more capable. She is beginning to stand, manipulate objects with her hand, and can communicate her desires.  The last is very important, because it means that the biggest obstacle to toilet training is taken care of, and her being able to communicate her desires removes much of the frustration that leads to tantrums.

T has begun copying his pre-kindergarten classmates more, and unfortunately the group he imitates is going through a baby talk phase. (we (the parents) have been able to trace it back to one girl in particular who is the origin of this).  We are hoping this is something that will pass in short order. In the meantime, we do not hesitate in letting him know we don't like it (generally emphasizing that to do fun stuff with us he has to make sure we know what he is saying!)

As she is able to do this, we are starting to identify divergence in how A and T developed. By the end of the first year, colic had already passed for T, although this still showed in delayed development.  But by this point T had begun displaying the focus and attention span that was beyond the norm for a toddler.  In contrast, A has the standard 1 year old length of focus (almost none) but she gives the impression of being thoughtful and smart. First, the fact that she is able to effectively communicate relatively specific and complex desires (given the fact that she cannot actually say any words.) She also can multi-task. If she is prevented from doing something, she can shift tasks until her original goal becomes attainable, she then drops what she is doing to get the original goal.  In contrast, T's main characteristic was persistence and focus, which in many cases overcomes lack of raw ability.

Making an ant at Animal Secrets, Carnegie Museum of Natural History
Building an ant

We are seeing that this will lead to different sets of challenges. Discipline with T was based on providing an object of focus, then encouraging him as he achieved his object.  A is more like other toddlers, shifts from object to object, but she will either succeed or fail quickly.  T liked to stay with things to completion. A will shift focus once her objective is realized.

All that is in the future.  Our current task, getting T ready for Kindergarten.  Mommy summer school is in full force.  Daddy school is going on outing and playing games :-P

Monday, May 25, 2015

Building The Family Handyman Ridiculously Simple Shop Stool

My latest project was the Ridiculously Simple Shop Stool. The goal of such a thing is to have something that is useful for sitting, a short step ladder, or as a fairly portable work surface. It is not necessarily pretty (hence it is called a 'shop stool' instead of a 'stepstool')
Plans for the Ridiculously Simple Shop Stool from The Family Handyman
Some important characteristics is that it is built from 1X dimensional lumber (so the wood is cheap) and it is all short straight cuts, which is important because I do not have a mitre saw, a table saw, or a router. 

My backyard workshop
My backyard workshop
First step was to cut the lumber. I got 1X3, 1X4, 1X6, and 1X8 lumber from The Home Depot. They cut each board once (that is there policy) so that I can fit it in my car.  I recently purchased a Rockwell Compact Circular Saw so I now could make straight cuts on 1X or 2X lumber, which was very helpful for this project.  A couple of nice features included the fact that it is small for a circular saw (single hand operation), so I could use it and a carpenters square without clamping.  Also, using bench cookies would stabilize the board by itself (small circular saw means less vibration).

Cut boards for making the Ridiculously Simple shop stool
Cut wood for two shop stools

Measure twice, cut once
Cutting boards with a Compact Circular Saw and a Carpenters square.

Next step was sanding the boards and staining them. I used a rasp to break the corners, then three rounds with sand paper.  Staining was with Dutch Oil.

Staining wood for step stools
Staining boards

For assembly the hard part was the fact that 1X dimensional lumber is prone to splitting. I split my first two, then I noted that the instructions say to pre-drill holes to prevent splitting.  After that it was a lot easier.

The next tricky part was getting the steps in. The side slabs make it hard to get access to the tops of the steps. I think pocket screws would work, if I was up to learning how to do pocket screws.  Another new purchase was a right-angle driver/drill head for my Rigdig Jobmax multi-tool. The advantage is that I can drive in wood screws without as much space as the average cordless screwdriver.

After getting all the supports and steps glued, pre-drilled, and screwed in, we had the structure of the shop stool.

Ridiculously Simple Shop Stool completed
Complete shop stool

Next was to put finishing touches on it.  Scrapped off the excess glue.  Added non-stick safety tape on the steps.  Added hinges so that the second half of the top can be opened to make a stool top or folded to allow for steps. Added felt pads on the feet and on the top to protect the floor and to soften the sound when the top is opened or closed.

Ridiculously Simple Shop Stool
Two completed shop stools in the kitchen

A nice little project. It turns out to require use of two new tools (the Rockwell compact circular saw and the Rigdig Jobmax Right Angle driver). It will get multiple uses, as stools my in-laws like to eat at the kitchen counter when they are at our place so they can use two stools.  The steps are tall enough that my 4-yr old son can now help food prep and operate the microwave. The stool tops are good for side tables in our living room (so we can sit at our couches and eat). They also make for good work surfaces in the kitchen (that will always be clear because we need to use them for other reasons).

Very nice project. Thanks to The Family Handyman for providing the plans.

Saturday, May 16, 2015

Cancun family vacation

We had a rare pure family vacation (meaning the trip did not include visiting friends, family, or other business). With two kids (preschooler and baby) and two grandparents, we went the easy way out and took a trip to a family-friendly all-inclusive resort in Cancun, Mexico. The benefits of an all-inclusive resort is that very little thinking or planning is required. The knock against these sort of things is that they are completely removed from the host area, which is true. But some memories and thoughts:
Touching the sea in Cancun
Touching the sea for the first time in Cancun, Mexico

1.  Using an all-inclusive resort made it possible to have a vacation while we are caring for two grandparents, and two small children. No worries about getting food, everything is in short walking distance, and we don't have to worry about getting lost in the general traffic of everyday life. And right now, that is important.  Someday, when T and A are older and going to different cities is meaningful, we will have that kind of vacation.

2.  We think that most of the staff are recruited from Quintana Roo>. And a large fraction of the guests were Mexican. So the resort we were at was not a Little America that I thought that these places would be.  We had T do greetings and simple questions in Spanish (e.g. hola, buenos dias, buenos tardes, __ por favor, donde es ___, gracias, de nada, numbers) And staff responded properly to a four year old American using Spanish. For T, who learns Spanish in pre-school, that means that he experienced hearing and using Spanish as a working language, not a memorization exercise that pre-school Spanish is. Bonus, there were a couple of times when S and T were interacting with housekeeping (which were not generally bilingual) and T knew just enough Spanish to get the point across.

3.  We provided the staff great amusement with my high-school Spanish. Sometimes, when the staff recognized me (or T) we would have our entire exchange in Spanish. We noticed this would happen when there was another staff observing in surprise, and the staff we interacted it would give them an amused smile at their surprise. This has the obvious implication that if my not-significantly-different-from-zero Spanish was cause of notice and amusement, the typical level of Spanish for an American is actually zero.

4.  T is still the very cautious and generally shy self. He had a few scary (for a four year old) experiences over the trip. He slipped and got stuck on a bunk bed ladder, he got turned on a water slide and went underwater, and he was on a jetski (being used as a lighter to another boat) punching its way through waves and up on a beach. So we had many conversations on how being brave was doing things that were scary, and not stopping even when things go wrong.

5.  For both T and A, the best part of the trip is clearly the fact that they had mommy and daddy close at hand for large parts of every day.  Frankly, they would have enjoyed this if we stayed at home too. But they also saw us interacting with the hotel staff. And (especially since we were trying to get T to practice his Spanish) doing so with courtesy, even when there were problems with the room and travel. (ok, if you asked T, he probably would say that parasailing and always-available ice cream were pretty significant too.)

6.  A is a very expressive one-year old. That means she babbles, dances, looks at people, and acts and speaks with intent. Very clear and specific intent. In a one-year old, this is seriously cute (and we hope this means we will skip the worst of the tantrum stage). But another part of us thinks that if she is like this now, just wait until she actually has language skills. As I recall, in daycare, there was a clear hierarchy based on who had language skills (they could communicate with each other, and communicate their desires to the teachers). T was on the bottom end of this until he was 3 1/2 or so. A is going to be at the upper end.

7.  T definitely recognized that he has to compete for attention. And it is very hard to compete for attention with an expressive one-year old. Especially when you are naturally an introvert. Knowing a little bit of Spanish helped in this weekend with the staff and the other Mexican guests, a preschooler trying to speak a second language is pretty cute too.

8.  We somehow chose a resort that was also hosting a Korean church conference.That was something you don't experience on the average vacation.

9.  Grandpa and T (and daddy) went parasailing (which involved using a jetski to get to and from the boat).  Grandpa was very happy at this little adventure.

We are glad we did this. Grandparents can probably only do this for a limited number of years, and the kids are not in a position to appreciate anything more complex. When our kids get older, they will better appreciate things that are more complex, more adventurous, or more immersive.  But this is a good start.

Thursday, May 07, 2015

Parenting Month 54: Many things to talk about

Wood tangrams
Homemade wood tangrams

This month's theme for both children has been expressiveness. Both of them have been growing in expressing themselves, which is a far cry from the previously very quiet in public T and a baby A.

T's expressiveness and confidence in public we still attribute to ATA (tae kwon do school).  He enjoys being good at something (which comes with practice), and now having passed two rounds of belt testing and one session of board breaking, he is gaining confidence that he can perform in public. So now in ATA class he cheerfully shouts out answers and ki-yup and yes sir/yes ma'am appropriately.  In preschool he now speaks regularly, which is a considerable change from even 6 months ago when he was very quiet. He still a relative island of stillness in the chaos that is the typical pre-school classroom, but he interacts more with others.

A has also become quite expressive. Last month she babbled and sounded like she was having a conversation.  Now when she babbles she is clearly doing so with intent, and she gets upset if you do not respond appropriately! Among things she can distinguish are toys, DVDs, books, and food.

Can you read this for me?
Will you read this book about going to the potty for me?
In other news, T has had his kindergarten orientation. After testing, and visiting the school for various events over the past two years, he is getting comfortable there. We were bemused to see that T was NOT the shy kid of the group, instead he was a bouncing little pea going along (he is young, and even for his age he is short, but not skinny).  His future teachers have noted that he has a good attention span, made evident during his visits to the classrooms, testing, and when he came to watch the school play (watched the play without the parents having to closely manage him).

A has become mobile. While she still really wants to walk (she cruises and occasionally attempts to stand without support), she does crawl. And she does crawl with intent (a destination in mind). Sometimes that intent may or may not include us, so we have to keep an eye on her (gege has to be tasked with being a watchdog at times).  Among other things, she has figured out how to get up the stairs (she is ok with backing down). Since she has determination, she has made it to the top floor before we've figured out where she was.

Saturday, March 28, 2015

Parenting Month 53: When Eagles fly

T's major events for the month were taking a trip and our first experience with high stakes testing.  By all accounts both went quite well. T has always been a good traveler, and the high stakes testing experience was one that was sane.

On their way to a flight
We need to go that way to get on our plane
This month was noted by mommy taking a work trip to Las Vegas, and we took T out of day care for the week and had him go along. Auntie P also went along, having been to Las Vegas before, but not in the company of a 4-year old. So amid lots of walking in the hotel, through a casino, to other hotels on the strip, we got many comments that he was a good traveler, standing patiently through many lines, and doing his job of pulling his own bag around and staying with mommy (or auntie). The flight itself was spent reading and playing. Even when tired, the worst he got was asking for a carry. It would be hard to expect any better from a pre-schooler. This was another instance where we pulled the 'you need to be a very good boy' on him prior to the trip. Of course, he also knew when the trip was over, so he reverted back to normal (which is still pretty good, but there is a notable difference. Weeks like this are where we want to ask if we can keep this child :-)

The other major event for the month was kindergarten testing. This is known as high-stakes testing in the pre-elementary world, because the test is being used to make choices on admission into a school.  Because T's birthday is in October, he would not be eligible for kindergarten next fall in our school district. Since he started pre-Kindergarten in November, that would imply that he has to repeat a year of something, either he takes Kindergarten next year at our daycare (which does offer Kindergarten) and then goes to Kindergarten again (when he is eligible for Kindergarten) or he repeats pre-K at the day care and goes to Kindergarten when he is eligible.  While there are arrangements to test into pre-K at the local school district, word on the street is that almost no one passes (to get into Kindergarten early, apparently the standard is test at a level of passing the year after the one you want to test into).  In addition, the public school Kindergarten is a half day kindergarten, so you still need to make arrangements for the other half day (which our day care offers).

So we are looking at a nearby Catholic school K-8. It is very highly regarded. In visits to the school we have noted the interaction between the kids and the staff, and also between older and younger kids (the 6-8th graders mentor the K-2 grade students). We like the smaller class sizes (our day care had a pre-K with 20 and a pre-K with 8 students. T responds to the difference).

The issue with high-stakes testing is that pre-school kids do not perform on demand, to having to make decisions with long-term effects based on a one time event, and the parents are fully aware that the kid's behavior is essentially random.

While the general concept of testing is rather insane, the concept of evaluation is not, a school needs to do an evaluation to determine if a child is ready, especially in a case like this where a child is trying to go above grade level (in the U.S. the pattern is to hold children back, so the effect of some parents holding children back and other parents pushing kids ahead is that there can be a 3 year range in ages. Later, the difference almost disappears, but at age 6, a three year range is very significant, so the school needs to know that the younger end of the range can handle it.

Hence, there is a little cottage industry of preparing pre-schoolers for high-stakes testing, especially in places like New York City where the better pre-schools and kindergartens are known and they get full. Because how the child performs in a span over a couple hours does make a long-term difference.

Fortunately for use, the evaluation at this school was sane. We have an ongoing relationship with the school, so T has visited a couple of open houses, another event, and has visited during a normal day. The school staff were aware that he has a record of not interacting with strangers, so we have been building the level of recognition over time with the staff who would do the evaluation. And the testing was only one part of an overall evaluation (which included observation of multiple interactions with the current Kindergarten students).

So he did pass and got accepted for next year. Does test preparation make a difference? We actually got test prep materials (yes there are such a thing), but in the end, while we did read them, we did not use them, with life generally getting in the way, and we spent our time with him doing other things. The book we have, Testing for Kindergarten by Karen Quinn, probably would have preferred it that way. The core of the advise was that the best way to prepare was to interact with the child over a long period of time and develop the skills needed that way.  But the reality is that formal test prep could have made a very big difference in a child's performance. I joked that in the efforts to make a test that was cultural and background neutral, the tests give a big advantage to one major group. People who prepare for pre-school hish-stakes testing. Many of the questions are based on the fact that a person understands the concept being tested and the form of correct answers. The test prep books and programs are somewhat built around making sure the child is exposed to the types of questions being asked and how they get answered. They also run through the various topics. While the topics of questions are all topics that children can get exposed to, to be exposed to the whole range almost requires deliberate test preparation.

Tiger mommy finds it ironic that having geared up for preparing for high-stakes testing a year ago (as we realized the effects of an October birthday and the implication that it would have essentially meant repeating a year someplace), we did not actually put time into test preparation. Instead, while mommy school did involve reading and arithmetic workbooks (and recently, music), daddy school involved going to museums and other places, doing wood projects, and building LEGO.  And we were applying to a place that did assessment, but did so in a sane manner as part of an overall assessment that worked with the characteristics of the child in question.

In other news, A also had an assessment done. She is somewhat behind in motor skills development (does not crawl) so we had the Alliance for Infants and Children come (a free program for those under 3 in PA). The assessments results were highly encouraging, they think that the delay in crawling is due to a physical characteristic, which is not a long term problem. But, they also evaluated other aspects of development. I was very amused at the report. It frequently references the fact that A likes to play with her older brother.and how that relates to the way she babbles and plays (even if she does not crawl).  I even had T read those parts of the report. :-)

Big brother is making Jello
Gege is making Jello. Can I have some?

A does not really crawl, although she is now at the point that she will get on all fours and rock (and sometimes even move!)  But she does enjoy pitcking up things, banging them together (almost) stacking items Particularly amusing is when she goes into babbling mode. It is as if she is trying to hold a conversation.

This past month of parenting has had its share of concerns, but we leave it thankful that our children are active and engaged in their world, even for any faults they may have.