Lance Bledsoe

The 9 best things about my first week (back) in the classroom

bledsoe — Thu, 25 Feb 2010 10:30:29 +0000

Last week I started a new job teaching high school math after several years being out of the classroom. The first week went pretty well. Here are the five best things about it (in no particular order).

Meeting Jimi Hendrix - No lie, James Hendrix works at my school. He goes by Jimi. (Wouldn't you?)
The congratulatory gift basket the guys in my band sent me - Actually I'm pretty sure just one guy did it and put everyone else's name on the card, but still this was way cool.
My oldest son is a student at my school - And he doesn't seem at all bothered by the fact that his dad works there. He almost seems to think it's cool. Before I started, I told him that I'd be really busy for the first few days and that I didn't want him coming by bothering me, and of course he ignored me. On my first day, he and a couple of his friends came by my room to say hi and it made me feel really good.
The other teachers in the math department - Even though they all have their own stuff to do, every time I've needed something they've been happy to help. One even loaned me a huge binder full of course notes, tests, etc., that she put together over the 10 or so years that she's been teaching the same course I'm teaching. Score!
The social studies department office - they have the best copier (no smudges!) and the best snacks, which someone brings regularly and puts on the table. Of course, I wouldn't eat any of them, since I'm not in the social studies department, but if I was going to eat some, those cookies from last week would have been really good.

How to turn off Wordpress smart quotes

bledsoe — Sat, 30 Jan 2010 18:43:02 +0000

Smart quotes (aka curly quotes) are what most word processor programs insert into your document when you type the quote marks key. They're pretty to look at, but they cause problems if you use them in a text document that contains code intended to be read by a computer. That's normally not a problem since text editors don't create smart quotes when you type the quote key, but if you happen to find a cool chunk of code on a blog somewhere and you cut and paste it into a text file, if the blog you're copying the code from uses curly quotes, then you have a problem.

The bad news is, Wordpress automatically converts all quote symbols to smart quotes, so if you post code snippets to your blog and they have quote marks in them, anyone who attempts to copy and paste that code into their own text file is going to have problems running the code. The good news is, you can turn this feature off.

There are actually a few different ways to do this, including modifying the functions.php file in your theme folder, or modifying the default-filters.php file in your wp-includes folder. But I like creating a separate php file and making it into a Wordpress plugin, as described in this post by Katja Stokley. Create a text file called TurnOffSmartQuotes.php and put this in it:

/*
Plugin Name: TurnOffSmartQuotes
Plugin URI:
Description: Stops Wordpress from converting your quote symbols into smartquotes. The three lines below stop the smartquote conversion in 1) your post content, 2) your comments, and 3) your post excerpts.
Version: 0.1
Author: Katja Stokley
Author URI:
*/
remove_filter('the_content', 'wptexturize');
remove_filter('comment_text', 'wptexturize');
remove_filter('the_excerpt', 'wptexturize');
?>

Then just upload this file to your wp-content/plugins folder, login to your Wordpress dashboard, select "Plugins," and activate your new plugin. You've just turned off smart quotes on your Wordpress blog.

Dilbert notes a problem with the survey methodology

bledsoe — Sat, 23 Jan 2010 11:49:35 +0000

Famous people commissioning surveys: The Dilbert Guy

How to align your custom header with your navbar

bledsoe — Thu, 21 Jan 2010 15:31:09 +0000

If you use the Thesis theme for your Wordpress blog, you might have created your own custom header image for your site (kind of like mine, above). If so, you may have noticed that your header image doesn't seem to align correctly with your navbar. To get your header image and your navbar aligned, you'll need to add a few lines of code to your Thesis custom.css file. It's a simple fix, and here's how you do it.

Click on the Thesis Custom Styling option under the Appearance menu in your dashboard sidebar. This allows you to make changes to your Thesis custom.css file. At the bottom of this file, insert the following lines of code.

/* The following lines control the alignment of your header image with your navbar. As long as these are all set to zero, your header image will be aligned with your navbar on the right and left, with no whitespace between the header image and the navbar.
*/
.custom #header {
padding-bottom: 0;
padding-top: 0;
padding-left: 0;
border-bottom: 0;
}

Save your changes, reload your blog page, and your header image and navbar will be aligned.

Removing the whitespace at the top of your Thesis blog

bledsoe — Tue, 19 Jan 2010 17:38:51 +0000

If you use the Thesis theme for your Wordpress blog, you might have created your own custom header image for your site (kind of like mine, above). If so, you may have noticed that there's a little bit of whitespace between the top of your browser window and the top of your header image (kind of like mine, above). If you want to get rid of that whitespace, you'll need to add a few lines of code to your Thesis custom.css file. It's a simple fix, and here's how you do it.

/* The following lines control the whitespace at the very top of the page (i.e., above the header image). If you set the padding-top property value to 0 (zero), your header image will be flush with the top of the page.
*/
.custom #page {
padding-top: 0;
}

You can also set the padding-top property value to something else if you actually want some amount of space between the top of the browser window and the top of your header image.

Save your changes, reload your blog page, and the whitespace will be gone.

Fox News mangles stats, denies error

bledsoe — Mon, 28 Dec 2009 02:14:30 +0000

A recent series of events at Fox News involved not only a mistake in reporting survey data, but a subsequent refusal to acknowledge the mistake, even after it was pointed out. The timeline of events is as follows:

On November 23, 2009, after a "series of [on-screen] mistakes," Fox News implemented a zero-tolerance policy for on-screen errors.
On December 1-2, 2009, Rasmussen Reports, a well-known public opinion polling firm, conducted a national survey to determine the views of Americans on the issue of global climate change. Survey question #3 asked, "In order to support their own theories and beliefs about global warming, how likely is it that some scientists have falsified research data?" Rasmussen reported the responses to this question as follows:

35% Very likely
24% Somewhat likely
21% Not very likely
5% Not at all likely
15% Not sure
On December 3, 2009, Rasmussen Reports published a summary of the results of the survey in which they noted, among other things, that:

"Fifty-nine percent (59%) of Americans say it’s at least somewhat likely that some scientists have falsified research data to support their own theories and beliefs about global warming. Thirty-five percent (35%) say it’s Very Likely. Just 26% say it’s not very or not at all likely that some scientists falsified data."

(This was in fact an accurate summary of the survey data from survey question #3.)
On December 4, 2009, Fox News broadcast a 1-minute segment in which a graphic (created by Fox News) was displayed which incorrectly summarized the data from survey question #3, and three commentators briefly discussed and interpreted these (incorrect) data.

On December 8, Media Matters for America, a non-profit media watchdog group, sent an open letter to Fox News pointing out the error in the Fox News graphic, and suggested that this might be a case that merited a reprimand under Fox's new zero-tolerance policy. Fox News responded that there was no error in the graphic, and thus no need for any reprimand.

If you look at the graphic, it seems pretty clear what happened: whoever created the graphic only read the Rasmussen summary of the survey data, and not the breakdown of the actual percentages for this question. This person no doubt assumed the three percentages quoted in the summary paragraph represented all of the answer choices for the survey question, when in fact the 59% number combined the responses for Very Likely and Somewhat Likely into a larger category of "at least somewhat likely." (This combining of response categories is done all the time when reporting on survey data.) The Fox News graphic implies that the Very Likely group is separate from the 59% "combined" category, when in fact it's a subset of it. As pointed out by a number of observers, reporting the percentages as Fox did clearly distorts the survey data, even making it appear that the total number of survey responses exceeded 100%.

While many people may disagree about the degree to which Fox News or Rasmussen Reports display a conservative bias, or the degree to which Media matters displays a liberal bias, or the appropriateness of some sort of reprimand under the Fox News zero tolerance policy, the one thing that is undeniable is that Fox News made a mistake when creating the graphic. Yet, when the error was pointed out, Fox News simply claimed that while "the presentation wasn't perfect," there was no error in the graphic.

While this wasn't perhaps the worst mistake ever made, it was a mistake, and while there's no shame in making a mistake, there is shame in attempting to cover it up. For a major news organization to refuse to acknowledge such a clear error in reporting simple facts is unconscionable.

Math conversations: The Maker explores division

bledsoe — Tue, 01 Dec 2009 16:32:57 +0000

In the car the other day, the Maker, currently in 4th grade, asked me what 100 divided by 3 is. (Sometimes when he asks me arithmetic questions, I'll just toss it back to him and ask him to tell me the answer, but I knew he'd been working on understanding division so I told him it was 33 and 1/3.) "And what's 100 divided by 4?" he asked. "Twenty-five," I said.

When it appeared that he wasn't going to ask anything else, I said, "And what's 100 divided by 5?"

That slowed him down for a minute. He suggested the answer was 30, but I pointed out that 5 times 30 was 150, so that wouldn't work. Then he suggested 29, then 28, and so on down to 26, each time adding up five of the number (in his head), attempting to find one that would add up to 100.

When he got to 26 and that one didn't work, he declared that the answer must be a fraction between 25 and 26.

I asked him how he knew the answer wouldn't be a number below 25, and after thinking about it for a minute, he started trying the "add the number to itself" approach with 24, then 23, and so on until he got to 20, at which point he declared this to be the answer.

Later, I asked him why he initially thought the answer had to be greater than 25, and he got a piece of paper to show me. He explained that he had gotten division confused with multiplication. If you have two multiplication problems, and one answer (i.e., the product) is greater than the other, yet one of the multiplicands is the same in both problems, then you know the other multiplicand must be greater than the corresponding multiplicand in the first problem. In division, it's kind of the reverse, since, as The Maker explained, multiplication and division are opposites. In other words, as the divisor gets larger, your answer (i.e., the quotient), gets smaller.

In this case, The Maker's reasoning was perfectly sound; he understood that there was a pattern in the division problems we were talking about, and he was systematically following the pattern to find the correct answer. The problem was that he was using the pattern for multiplication rather than the pattern for division. Once he worked his way to the correct answer for the problem he was working on, he realized his mistake.

A professor at Swarthmore College, Heinrich Brinkmann, is said to have been well-known for being able to find something right in what every student said. No matter how outrageous a student's contribution or question, he could respond, 'Oh, I see what you are thinking. You're looking at it as if...'" (See the book, Math Power: How to Help Your Child Love Math, Even If You Don't.)

What a wonderful trait for a teacher (or parent) to have. As Jo Baeler notes in her book What's Math Got To Do With It?, "unless a child has taken a wild guess, there will be some sense in what they are thinking - the role of the teacher is to find out what it is that makes sense and build from there."

Vonage vs. VOIPo

bledsoe — Wed, 11 Nov 2009 14:00:15 +0000

A few months ago I compared my three-year experience with Vonage to my 6 month experience with Skype. After my Skype phone died, I decided to try VOIPo, the new VOIP service from HostGator, and wanted to share my experience with them.

VOIPo customer service can't be beat. Though it's not available 24/7 (only 9-7 Central, M-F), they're really good. Minimal hold times, the reps are technically competent, and they speak to you without a script, just like you're a real person. The few times I spoke with Vonage customer service, they were always trying to sell me some additional feature that I didn't want.

The prices are pretty similar. I give VOIPo a slight edge here, but only a slight one. It takes a little work to cut thru all the verbiage to get to the real price of the service, but once you do, you find the following:

VOIPo's introductory rate comes out to $11.25 a month, once you include the $36 annual taxes and fees, and assuming you buy a whole year of service at one time.
VOIPo's standard rate comes out to $19.67 a month, again including the $36/year taxes/fees and the annual contract, though according to VOIPo existing customers can always take advantage of any special promotional pricing that's being offered. So if the $11.25 a month price is available, you can always buy another year (or more) at that price.
Vonage's standard rate for its most popular plan with an annual contract (which they call Annual Prepay) is $239.99 a year (including all taxes and fees), which comes out to $20 a month, almost identical to VOIPo's standard annual price. Though Vonage publicizes this plan as costing $24.99 a month (with no annual contract), my experience with Vonage was that once taxes and fees were added in, that price was never less than $30 a month for me; if you get this plan with Vonage, I definitely recommend the Annual Prepay option.

When it comes to call quality, I found Vonage and VOIPo to be almost identical. Both provide high-quality sound, every bit as good as any standard landline. They also both have a nice online interface which you can use to check voicemail, set call forwarding, etc., though I found VOIPo's to be much simpler and easier to use.

Bottom line: I like VOIPo and plan to stick with it, though Vonage's features, quality, and prices are comparable, especially if you go with their Annual Prepay option.

I suspect at some point my wife and I will drop the landline altogether and just use our cell phones, but right now it's still handy to have a VOIP home phone line, especially since a) I work a lot from home and b) we have three teen/pre-teen sons and don't plan on getting cell phones for them.

How to change OpenOffice chart colors

bledsoe — Fri, 23 Oct 2009 17:48:32 +0000

As a frequent user of the OpenOffice apps, including the Calc spreadsheet (oo's version of Excel), I occasionally need to create a chart from some of my data. Typically, I'll create a pie or bar chart in Calc, then copy and paste it into Writer (oo's version of MS Word). Recently I created two pie charts from similar data and I needed the colors of the pie slices to be the same for corresponding categories in each chart; in other words, I had a Category A in Chart 1 and a Category A in Chart 2, and I wanted the pie chart slices for Category A to be the same color of blue in both Chart 1 and Chart 2.

I didn't figure this would be a huge problem, especially since when I created the charts in Calc, it gave the corresponding categories the same colors without me having to do anything. Unfortunately, when I copied and pasted the charts into Writer, Writer changed the colors! Wha?

I figured I would just manually set the proper color for each pie slice, but it's not at all obvious how to do this simple task, and the oo help documentation isn't that helpful. Here's what you do:

After pasting your chart into Writer, single-click the chart to make sure it's selected.
Double-click the chart to put it in "Editing mode."
Single-click on the pie; this will make a series of small green squares appear on your pie slices, one green square per pie slice.
Single click on one of the pie slices; this will select that one pie slice.
Double-click on this same "selected" pie slice; this will bring up the "Data Point" dialog box. Select the "Area" tab and select "Color" in the dropdown box.
Select the color you want the pie slice to have and click Save.

Repeat steps 4-6 for each pie slice and you're done. The key is to single-click and/or double-click at the right time and place; if you don't, you won't be able to get to the correct "Data Point" dialog box.

I'm not sure why Writer decided to spontaneously change my chart colors this way, but if any oo programmers happen to be reading, this might be a good thing to fix in the next release.

Book Review – The Drunkard’s Walk

bledsoe — Thu, 08 Oct 2009 18:01:27 +0000

Just wanted to send a quick shout out for The Drunkard's Walk, a really neat book on "how randomness rules our lives," written by Leonard Mlodinow, a physicist at Caltech and a collaborator with Stephen Hawking on the book A Briefer History of Time.

When I write a review of a math-related book, I generally assume that it will be largely ignored by anyone's who's not a math geek. While that may often be true, in this case I happen to know for a fact that this book has appeal beyond the math geek crowd because after I mentioned Mlodinow's description (in Chapter 3) of the controversy that surrounded a fairly well-known math problem (the Monty Hall Problem), my wife was so fascinated that not only did she read the chapter for herself, she actually wrote a blog post about it.

In much the same way that Levitt and Dubner's book Freakonomics drew us into the use of economics by applying it to fascinating real-world examples, Mlodinow draws us into understanding the role of probability and randomness in our lives by exposing the flaws in the way we typically think about a number of common situations such as the skill of successful stockbrokers, the quality of wine and vodka, and what makes a really good actor. Often, where we think we see clear patterns or signs of cause and effect, what we really see is just the role of chance.

Mlodinow really does an excellent job at making a confusing subject a little less confusing, and he also makes us feel a little better about how confused we all are by reminding us of Martin Gardner's comment that "in no other branch of mathematics is it so easy for experts to blunder as in probability theory."