See How Yearbook Photos Have Evolved Over the Past Century

Cornell University Library
Cornell University Library

High school picture day is a tradition that dates back to the beginning of the 20th century. And while the basic formula of a front-facing pose against a neutral background hasn’t changed much in the past 100 years or so, facial expressions certainly have. For a better look at the similarities and differences between yearbook photos through the decades, researchers from the University of California, Berkeley recently compiled data on tens of thousands of images from the past 110 years [PDF].

The team's research marks one the first times machine-learning algorithms have been used to mine historic data from a collection of photographs. The high school yearbook photos were gathered from the digital databases of local libraries across the U.S. After downloading 150,000 pictures, the team eliminated all the photographs that weren’t front-facing portraits, leaving them with 37,000 samples from over 800 yearbooks from 26 states.

Next, they generated an “average” image for the men and women of each decade. By superimposing the groups of portraits together, they were able to then identify any trends exhibited in the composite images. One of the more interesting changes these pictures showed was the evolution of the subjects’ smiles.

When photography was still gaining popularity at the turn of the 20th century, it was normal for people to adopt a neutral expression for their portraits. According to the authors of the study, the earlier expressions might were partly a product of the beauty standards of the time: "Etiquette and beauty standards dictated that the mouth be kept small—resulting in an instruction to 'say prunes' (rather than cheese) when a photograph was being taken." (Not, it should be noted, due to long exposure times. By the late 19th century, innovations in photography had cut exposure time down to mere seconds.) 

As the 20th century wore on, the classic posed smile we adopt today began to emerge. An algorithm measuring the yearbook photos' shifting degrees of lip curvature supports this, and the trend can also be clearly observed in the composite images. Notably, this was around the same time that Kodak began releasing advertisements of happy people "smiling for the camera." The authors of the paper suggest this had a significant impact on how people chose to pose for their pictures.

The process also revealed data-backed proof of shifting trends in other areas, such as average hairstyles for each decade. While women of the '30s rocked finger waves, pin curls dominated the '40s and '50s, Afros took over in the '70s, and perms and bangs had their moment in the '80s and '90s. The data the team gathered on the progress of male fashion was slightly less interesting: men have been wearing standard suits in their high school yearbook pictures for over a century. 







Images Courtesy of the Cornell University Library.

[h/t: MIT Technology Review]

7 Top-Rated Portable Air Conditioners You Can Buy Right Now

Black + Decker/Amazon
Black + Decker/Amazon

The warmest months of the year are just around the corner (in the Northern Hemisphere, anyway), and things are about to get hot. To make indoor life feel a little more bearable, we’ve rounded up a list of some of the top-rated portable air conditioners you can buy online right now.

1. SereneLife 3-in-1 Portable Air Conditioner; $290

SereneLife air conditioner on Amazon.
SereneLife/Amazon

This device—currently the best-selling portable air conditioner on Amazon—is multifunctional, cooling the air while also working as a dehumidifier. Reviewers on Amazon praised this model for how easy it is to set up, but cautioned that it's not meant for large spaces. According to the manufacturer, it's designed to cool down rooms up to 225 square feet, and the most positive reviews came from people using it in their bedroom.

Buy it: Amazon

2. Black + Decker 14,000 BTU Portable Air Conditioner and Heater; $417

Black + Decker portable air conditioner
Black+Decker/Amazon

Black + Decker estimates that this combination portable air conditioner and heater can accommodate rooms up to 350 square feet, and it even comes with a convenient timer so you never have to worry about forgetting to turn it off before you leave the house. The setup is easy—the attached exhaust hose fits into most standard windows, and everything you need for installation is included. This model sits around four stars on Amazon, and it was also picked by Wirecutter as one of the best values on the market.

Buy it: Amazon

3. Mikikin Portable Air Conditioner Fan; $45

Desk air conditioner on Amazon
Mikikin/Amazon

This miniature portable conditioner, which is Amazon's top-selling new portable air conditioner release, is perfect to put on a desk or end table as you work or watch TV during those sweltering dog days. It's currently at a four-star rating on Amazon, and reviewers recommend filling the water tank with a combination of cool water and ice cubes for the best experience.

Buy it: Amazon

4. Juscool Portable Air Conditioner Fan; $56

Juscool portable air conditioner.
Juscool/Amazon

This tiny air conditioner fan, which touts a 4.6-star rating, is unique because it plugs in with a USB cable, so you can hook it up to a laptop or a wall outlet converter to try out any of its three fan speeds. This won't chill a living room, but it does fit on a nightstand or desk to help cool you down in stuffy rooms or makeshift home offices that weren't designed with summer in mind.

Buy it: Amazon

5. SHINCO 8000 BTU Portable Air Conditioner; $320

Shinco portable air conditioner
SHINCO/Amazon

This four-star-rated portable air conditioner is meant for rooms of up to 200 square feet, so think of it for a home office or bedroom. It has two fan speeds, and the included air filter can be rinsed out quickly underneath a faucet. There's also a remote control that lets you adjust the temperature from across the room. This is another one where you'll need a window nearby, but the installation kit and instructions are all included so you won't have to sweat too much over setting it up.

Buy it: Amazon

6. Honeywell MN Series Portable Air Conditioner and Dehumidifier; $400

Honeywell air conditioner on Walmart.
Honeywell/Walmart

Like the other units on this list, Honeywell's portable air conditioner also acts as a dehumidifier or a standard fan when you just want some air to circulate. You can cool a 350-square-foot room with this four-star model, and there are four wheels at the bottom that make moving it from place to place even easier. This one is available on Amazon, too, but Walmart has the lowest price right now.

Buy it: Walmart

7. LG 14,000 BTU Portable Air Conditioner; $699

LG Portable Air Conditioner.
LG/Home Depot

This one won't come cheap, but it packs the acclaim to back it up. It topped Wirecutter's list of best portable air conditioners and currently has a 4.5-star rating on Home Depot's website, with many of the reviews praising how quiet it is while it's running. It's one of the only models you'll find compatible with Alexa and Google Assistant, and it can cool rooms up to 500 square feet. There's also the built-in timer, so you can program it to go on and off whenever you want.

Buy it: Home Depot

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Google Teams Up With The Conscious Kid on a Book List to Promote Racial Equity in Classrooms

Tomi Adeyemi's Children of Blood and Bone is on the list, and for good reason.
Tomi Adeyemi's Children of Blood and Bone is on the list, and for good reason.
Craig Barritt/Getty Images for Glamour

Google has teamed up with The Conscious Kid—an organization that promotes racial equity in education—to curate a list of books and other resources aimed at helping teachers establish more inclusive classrooms and foster conversations about racism and acceptance.

The reading list groups works by grade level, and many of them have corresponding teaching guides with discussion questions, writing prompts, and other activities [PDF]. For Lupita Nyong’o’s Sulwe, which tells the story of a young girl bullied because of her dark skin, students in preschool through second grade are presented questions like “Why do you think Sulwe believes she must have lighter skin in order to make friends? What advice would you give to Sulwe?” For Tomi Adeyemi’s Children of Blood and Bone, high-schoolers are asked to create a travel brochure for the fictional country of Orïsha, “emphasizing its positive aspects and great variety.”

The online packet also contains a number of guidelines for teachers to consider when choosing their own reading material. One helpful tip, for example, is to re-evaluate the “classics” before assigning them to make sure they don’t reinforce racist, sexist, anti-Semitic, or other harmful messages. Another is to foster healthy racial identity by avoiding books “where characters of color can only succeed when conforming to white values or norms.”

It’s part of Google’s broader campaign to amplify diversity in public education by providing educators with the resources needed to do it. Last year, the company donated $5 million to DonorsChoose—a platform that teachers can use to crowdsource funds for classroom projects—for the launch of #ISeeMe, an initiative that highlights projects submitted by Black and Latinx teachers, as well as those that focus on diversity and inclusion. This year, Google pledged an additional $1 million to matching donations made to #ISeeMe projects.

You can see The Conscious Kid’s full reading list here [PDF], and learn more about contributing to #ISeeMe projects here.