Speed Perception & Lighthouse with Estelle Weyl & Parvez Ahammad
No one likes slow loading webpages, but what aspects of page loading contribute to user perception of speed & how can we measure it?
Since people primarily consume the web visually, the visual perception of the webpage loading process should be of primary importance. Traditional web performance metrics defined in W3C standards are objective metrics, focusing on timing each process along the content delivery pipeline, such as Time to First Byte (TTFB) & Page Load Time. What metrics are most correlated with how human end-users perceive the webpage loading process: the above-the-fold rendering in particular? Well discuss how we can try to objectively measure something as subjective as the notion of feels fast.
Speed Perception: Measuring Perceived Performance
Sites need to feel like theyre fast: perceived performance is key. Making it feel 25% faster is a valid goal, but perception is subjective & we need to demonstrate subjective improvements with objective measurements. Oddly, studies show perf metrics dont provide much insight into perceived performance. In this talk, well look at what page load aspects affect speed perception, introduce the Perceptual Speed Index (PSI) which is a component of Lighthouse, & discuss the results of the first SpeedPerception.com study which have led to a combo-metric that models speed perception, which we are currently studying in phase 2.
Clearly, no one likes slow loading webpages, but what aspects of page loading contribute to human end-user perception of speed? SpeedPerception is an open-source experimental framework & a study that we developed to understand what slow & fast mean to the human end-user.
Traditional web performance metrics defined in W3C standards focus on timing each process along the content delivery pipeline, such as Time to First Byte (TTFB) & Page Load Time. We wanted to tackle the web performance measurement challenge by looking at it from a different angle: one which puts user experience into focus. Since people primarily consume the web visually, we focused on the visual perception of the webpage loading process. SpeedPerception is a systematic study of how human end-users perceive the webpage loading process: the above-the-fold rendering in particular: objectively measuring the subjective notion of feels fast.
Studies have shown that instead of only focusing on page load time, if we shift the focus to address perceived performance directly, we can make our web applications feel even faster even if we have to download the same number of bytes. What metrics do we need to measure to objectively test if a site load feels fast? Were looking into the impact of blanks screens, long DOMContentLoaded events, pop ups, passive versus active wait times, jitter, & other factors have on perceived performance, & how to measure the improvements in these features. We looked at browser metrics like time to first byte, render start, visual completion, etc., to construct a fusion model that can give the most insight into subjective judgments of Speed Perception.
Speaker:Estelle Weyl
https://lh6.googleusercontent.com/vlgH4NueJigE4yggQlI_c_0Lj53sDlRAVEUyPuFUm2aF2D8GItRUsrjI1HUSrcpFjPKzJtWWQLoo61ouEnNZHEOtWZfFXPPvF-3PGm6kDSvfDM9kZl7N8BYoB6gmWyOSKIM34wPp
Estelle Weyl (@estellevw) started her professional life in architecture & then managed teen health programs. In 2000, Estelle took the natural step of becoming a web standardista. She is the Open Web & performance evangelist for Instart Logic & has consulted for Kodak Gallery, SurveyMonkey, Samsung, Yahoo, Visa, & Apple, among others. She is a coauthor of Mobile HTML5, CSS3: The Definitive Guide, & HTML5 & CSS3 for the Real World. While not coding, Estelle works in construction, de-hippifying her 1960s throwback abode.
Speaker:Parvez Ahammad
https://lh6.googleusercontent.com/N1Z1U63V4YlN8LynrDFLlilJAyBngU44WxPJvRL8YRXPzMlshPM6xpgvi0kUlxrE71vg67NnvcAPgJ3gzhBZudi3g6fvX8flkonAKk_jUG0vG5yyvnDNGi7JexpNKS1QDDAp-8jG
Parvez Ahammad (@perceptPA) leads the data science & machine learning team at Instart Logic. His group is focused on creating data-driven algorithms, & innovative product features that optimize & secure web application delivery at scale. Parvez has a PhD in Electrical Engineering & Computer Sciences from UC Berkeley, with an emphasis in computer vision & machine learning. When hes not busy designing algorithms to mimic human perception, he enjoys being a dad to his two young kids & perfecting new ways to make them laugh.
Event details
Note: Price: $10 online, $15 at the door. No refunds. No ticket transfers.
We charge this small fee to help reduce no-shows. Please contact the organizers (sfhtml5 at gmail dot com) if this is a financial hardship for you.
Schedule
5:00 PMDoors open, eat & drink (food & drinks catered by Google; limited veg/GF options available; special cocktail by Alcademics; wine tasting by Grant Marie Winery.
Note: The event is on the 7th floor.
6:30-6:40 PMAnnouncements
6:40-8:00Speed Perception: Measuring Perceived Performance" with Estelle Weyl & Parvez Ahammad
8:00-8:30 Break
8:30-8:35 Lightning Talks*
8:35-9:00 PM Q&A with both speakers
9:00 PM Raffle -- have a chance to win a Google Pixel phone or a Google Home (must be present to win)!
9:30 PMRoom cleared
* Contact the Organizers if you'd like to give a lightning talk.
** You must be present at the venueto qualify for raffle prizes.
Notes
* There is bicycle parking in the garage below the building, but you must bring your own lock & leave your bicycle at your own risk.
* There is also street & garage parking. Check all signs for restrictions & fees.
* Smile! We are recording & photographing this event. If you do not wish to be included in SFHTML5 video or audio recordings or photographs, you can watch the recordings of all of our events atbit.ly/sfhtml5videosfrom the comfort of your home.
Cocktails by Alcademics
Wine Tasting by Grant Marie Winery
