resources
visualizations
presentations
lunch break
Distractions and amusements, with a sandwich and coffee.
Alex — Internet's Most Popular Rat
Poster Rat for Rat Genome Sequencing
|
The rat genome sequencing project at the Baylor College of Medicine Human Genome Sequencing Centre is complete. The genome has been analyzed and published. I'd like to introduce you one of the faces of the project: Alex, the genomics rat idol. Arguably, Alex is the most popular rat on the internet. For the justification of this strong statement, read on. 
▲ Alex, the rat. Rattus norvegicus on an ABI 3700 genome sequencer.
(zoom)
▲ Alex, the rat. Rattus norvegicus on an ABI 3700 genome sequencer.
(zoom)
Alex's BiographyAlex was born in May 2000. It's well known that a rat's cuteness reaches maximum at about 3-4 weeks. After this critical time, a pet store rat is less likely to be purchased and may be asked to act as snake food. In Alex's case, she was perilously close to her deadline. Luckily for her, we paid a ransom of $6.99 to the Noah's Ark pet shop in Vancouver. She was on her last cute leg. 
▲ Portrait of Alex, the genome rat (Rattus norvegicus). Here, she is seen in a forced portrait position
(zoom)
From May 2000 Alex spent most of her time hoarding food pellets and riding on shoulders. 
▲ Portrait of Alex, the genome rat (Rattus norvegicus). Riding on shoulder.
Alex liked to bite. And rats only bite hard — they don't nibble. Her contention for this unattractive behaviour was the uncanny similarity between a finger and a pellet of food. Other than unpredictable bouts of biting (by far the most exciting aspect of her personality), Alex lacked other distinguishing characteristics. Alex died of a seizure in late 2002. She was buried outside of the Museum of Anthropology. A ratty pair of underwear served as a burial shroud. And I hope you got that last pun. |
DOWNLOAD ALL PHOTOS.
Photos are for public use. Use, modification and distribution of these photos is unrestricted. Alex's PopularityDespite my best efforts at meaningful work, this web page continues to be the most popular of all my online offerings, making for a somewhat embarrassing achievement. Alex's images consistently show up first in Google's web search for 'rat', 'rat image' and image search for 'rat'. 
▲ Alex image is the first for Google's 'rat' search query (retrieved 16 Mar 2013).
(rat Google search)
▲ Alex image is the first for Google's 'rat image' search query (retrieved 16 Mar 2013).
(rat Google search)
Finally, Alex appears as the first entry in Google images for 'rat'. 
▲ Alex image is the first for Google's 'rat image' search query (retrieved 16 Mar 2013).
(rat Google search)
Alex's Public AppearancesAlex is neither without modesty nor public fame. Her first cover-ratgirl appearance was on the April 2004 issue of Genome Research. 
▲ Alex the rat appeared on the cover of Genome Research (April 2004).
(zoom)
More recently, she's appeared on the cover of Ethnologie Francaise (Jan-Mar 2009 issue). 
▲ Alex the rat appeared on the cover of Ethnologie Francaise (1/2009).
(zoom)
The topic of the issue was the relationship between animals and humans. It is fitting therefore to recount here the relationship I shared with Alex during her sojourn with us. |
news + thoughts
Curse(s) of dimensionality
There is such a thing as too much of a good thing.We discuss the many ways in which analysis can be confounded when data has a large number of dimensions (variables). Collectively, these are called the "curses of dimensionality".
Some of these are unintuitive, such as the fact that the volume of the hypersphere increases and then shrinks beyond about 7 dimensions, while the volume of the hypercube always increases. This means that high-dimensional space is "mostly corners" and the distance between points increases greatly with dimension. This has consequences on correlation and classification.
Statistics vs Machine Learning
We conclude our series on Machine Learning with a comparison of two approaches: classical statistical inference and machine learning. The boundary between them is subject to debate, but important generalizations can be made.Inference creates a mathematical model of the datageneration process to formalize understanding or test a hypothesis about how the system behaves. Prediction aims at forecasting unobserved outcomes or future behavior. Typically we want to do both and know how biological processes work and what will happen next. Inference and ML are complementary in pointing us to biologically meaningful conclusions.
Statistics asks us to choose a model that incorporates our knowledge of the system, and ML requires us to choose a predictive algorithm by relying on its empirical capabilities. Justification for an inference model typically rests on whether we feel it adequately captures the essence of the system. The choice of pattern-learning algorithms often depends on measures of past performance in similar scenarios.
Bzdok, D., Krzywinski, M. & Altman, N. (2018) Points of Significance: Statistics vs machine learning. Nature Methods 15:233–234.
Background reading
Bzdok, D., Krzywinski, M. & Altman, N. (2017) Points of Significance: Machine learning: a primer. Nature Methods 14:1119–1120.
Bzdok, D., Krzywinski, M. & Altman, N. (2017) Points of Significance: Machine learning: supervised methods. Nature Methods 15:5–6.
Happy 2018 `\pi` Day—Boonies, burbs and boutiques of `\pi`
Celebrate `\pi` Day (March 14th) and go to brand new places. Together with Jake Lever, this year we shrink the world and play with road maps.
Streets are seamlessly streets from across the world. Finally, a halva shop on the same block!
Intriguing and personal patterns of urban development for each city appear in the Boonies, Burbs and Boutiques series.
No color—just lines. Lines from Marrakesh, Prague, Istanbul, Nice and other destinations for the mind and the heart.
The art is featured in the Pi City on the Scientific American SA Visual blog.
Check out art from previous years: 2013 `\pi` Day and 2014 `\pi` Day, 2015 `\pi` Day, 2016 `\pi` Day and 2017 `\pi` Day.