Chapel Hill Flooding Video

I was eating lunch downtown at Mint with Joe and Anli when the heavy rains rolled in last Friday. We tried to wait it out, but it didn’t follow the usual pattern of a brief summer storm. After about an hour, it was still a decent shower, but Anli and I decided walk the six blocks or so to where we needed to be. Not sure what happened to Joe.

We were pretty soaked from the rain when we encountered a section of Franklin Street that was completely under a foot or so of water. After wading halfway, a whirlpool developed over the partially blocked drain.

I shot this video and later uploaded it to WRAL, where it was featured several times on the evening news.

Science Online 2010

The fourth Science Online conference just wrapped up, and it was as lively as ever. Unfortunately, my attendance was limited since I was coming down with a cold. I attended only a couple of sessions and tried to keep interactions to a minimum, which was hard to do at such an interactive conference with many friendly and familiar faces from previous years. Good thing I’ve been practicing most of my life at keeping to myself.

It was nice to see JMP 8, the product I help develop, on the desktop of one of the presentation machines, though I didn’t find out whose machine it was.

I did make it to Tara Richerson‘s session on Scientific Visualization, even though it was in a small conference room at about 3x capacity. (The facilities at Sigma Xi RTP were otherwise excellent.) She did a good job leading the discussion, especially considering the broadness of the topic and of the diversity of the audience. Given the amount of interest, visualization could be a separate track onto itself in the future. Tara posited that a good (online) visualization has: Story + Interactivity + Glanceability.

Stella at One

Our new puppy, Stella, turned one year old this week-end. She’s a very light coated golden retriever, a cross between the American and British types in hopes of reducing inbred genetic faults. So far she’s been quite healthy and full of puppy energy. I’m sure any day now she’ll realize she’s grown up and settle down, but for now she still plays hard:


and sleeps hard:


and chews holes in rugs when not entertained:


Chapel Hill Election Clustering Revised

I’ve updated the cluster analysis based on comments received. Thanks to Ed Harrison, I have included data from the Durham County precincts. And since other commenters explained away the apparent under-voting in some precincts, I recalculated the percentages to be based on the number of people voting in that race instead of the total ballots cast for the precinct. For town council, I approximated 4 votes per person which is necessarily on the high side, but makes the town council percentages comparable to the mayor percentages.

Two-way cluster of precincts and candidates
Two cluster of precincts and candidates

I also figured out how to color the clusters by absolute values rather than relative values, which helps to differentiate the candidates. They still fall into two large groups, but now it’s easier to see subgroups. Mayor-council alignments are highly sensitive to the council multiplication factor (4 here), so ignore Kleinschmidt and Czajkowski for candidate clustering.

For the record, low scoring candidates have been eliminated (otherwise they make all precincts look more similar), and absentee and provisional votes have been combined with One Stop precincts.

The precincts present a similar clustering as before, except the under-voters are now distributed into other clusters. The yellow group is fairly neutral. The green group is left leaning. The purple group is left-leaning with a focus on Harrison/Rich/Easthom. The blue group is left-leaning with a focus on Merritt/Kleinschmidt. The red group is right-leaning and includes two of the Durham precincts.

As a bonus, I thought this visual was attractive. It shows a smoothed trend line of the vote percentages (times four for town council candidates) by precinct, where the precincts are ordered by support for Kleinschmidt, the winner of the race for mayor. (Click graph for a larger version.)


The “left-leaning” candidates generally rise with Kleinschmidt while the “right-leaning” candidates (dotted lines) fall. Merritt’s strong showing at Lincoln and Northside is also evident. Unfortunately for him, those precincts had very low turn-out.

Chapel Hill Election Clustering

Damon Seils provided some great maps of the precinct results from this month’s local elections. I played around with the data, and found the results of a two-cluster analysis to be interesting. The ballots don’t include party affiliation, but candidates fell into two clusters, anyway, and the precincts fit several different profiles in support of those two candidate groups.

Two-way clustering of candidates and precincts
Two-way clustering of candidates and precincts

I’ll agree the diagram looks a bit complicated, but if you put in a little work, there’s a few gems to be found. Precincts are listed down the left side, and candidates across the bottom. The square at each precinct-candidate intersection is colored according to the candidate’s relative support at that precinct, red being strong, gray medium and blue weak. That part’s called a cell plot or heat map.

The tree-like parts are dendrograms, which show the results of the hierarchical cluster analyses. Similar items (precincts or candidates) are grouped together in the tree.

For the candidates, along the bottom, there’s a clear pair of clusters, which I’ll call left-leaning and right-leaning candidates. Coincidently, the left-leaning are on the left and the right-leaning are on the right.

The precincts are more interesting, though I have even less knowledge of their actual political orientations. I’ve colored the precincts into five groups. The first (red) and to a greater extent the second (yellow) cluster generally voted in favor of the right-leaning candidates. That is, the left six columns of the heat map are bluish and the right four columns are reddish. The opposite is true for the green and purple clusters; they’re more left-leaning, especially the purple precincts.

What puzzles me is the middle (blue) cluster. Those precincts don’t seem to like anyone. The numbers I used for clustering were percent of ballots cast, and apparently there were more voters in those precincts with incomplete ballots, voting in some but not all races. For instance, the two major mayoral candidates, Kleinschmidt and Czajkowski, only received votes on 28% and 21%, respectively, of the ballots at the Kings Mill precinct.

That leads to looking at votes per ballot for each race by precinct. Here’s a bar chart with the precincts ordered by town council votes per ballot.


Most precincts had near 100% participation in the mayoral race (exactly 100% for Booker Creek and Coker Hills), and most precincts averaged over three (of four available) votes in the town council race. So only the already-identified cluster of three (plus Dogwood Acres to a lesser degree) stand out regarding participation.

I imagine the One Stop (early voting for all precincts) totals reflect a lot of Carrboro voters. What makes the others different? Were people there to vote for a different race, like the school board? Or just voting for a favorite son/daughter candidate?

Small Town News

It’s not a prank, but I do have a little comedy for April Fool’s Day. “Small Town News” is probably my favorite segment on Letterman these days, and last week I submitted this item to the show from the Chapel Hill News Police Blotter section.

It’s not A material, but maybe it will make it on the show.

My favorite Small Town News piece involved a newspaper photo of an empty field and a fence. The caption read something like “Charles Smith reported two falcons on his fence Tuesday, but they had flown away before our photographer arrived.”

Gluten Freendly

I’ve been living gluten free since I tested positive for Celiac Disease about 8 months ago. That means no wheat, rye, or barley. Except the convenience of foods like pizza, sandwiches and crackers, I don’t feel like I’m missing too much thanks to Bonnie and local grocery markets that have lots of gluten-free alternatives. Gluten-free bread and pizza are just passable, but Pamela’s gluten-free pancake mix is as good as any.

Eating at restaurants is tough, but some are accommodating. As I learn which places or menus are friendly to gluten-free diets, I identify them as “gluten-freendly”. Amazingly, Google currently reports no hits for the two word term, so I’ll have to start promoting it. Maybe I should add a Wikipedia article on the topic …

Most high end local restaurants are gluten-freendly in that the staff is aware of gluten and can both point out gluten-free dishes and get the kitchen to make substitutions on other dishes. The Lantern in Chapel Hill and Acme in Carrboro both fall into that category. A couple of chain restaurants that are gluten-freendly are Bonefish Grill and PF Chang’s. Both have separate gluten-free menus. Most soy sauce contains wheat, but PF Chang’s will substitute a gluten-free soy sauce; I just wish they would put a little flag or something on the gluten-free plate so I could be more confident that it’s not getting mixed up with others.

Italian is out, but Indian restaurants are fairly safe, and Mexican places usually have a couple corn tortilla dishes. They will also substitute corn tortillas in other dishes, but the ones I’ve had were smaller and too weak to hold a burrito together well.