Konstantinos Stouras @stourask
A mathematician who, due to a miscalculation, works in a Business School. stouras.com Joined December 2017-
Tweets1K
-
Followers219
-
Following466
-
Likes1K
If you read Eliyahu Goldratt's "The Goal", you will know that a system's output is held hostage by its single slowest point. "The Goal" is a book I always recommend to professionals, because it gives the lightbulb moment. Improve anything except the bottleneck, and you have improved nothing. In reality, what happens is that far too many people spend years polishing stations that already run well, while completely neglecting that one upstream block which has been starving their entire career line. Wouldn't it be awesome if you knew what that block was, and what moves to take to fix it?
I am so happy to see this out, and I hope you will read and enjoy the paper! It took a while, but I am proud of how it turned out! We have been working on a package to implement it all: bcallaway11.github.io/contdid/ And I can tell you that much more is coming! So stay tuned!
Forthcoming in the AER: "Difference-in-Differences with a Continuous Treatment" by Brantly Callaway, Andrew Goodman-Bacon, and Pedro H. C. Sant'Anna. aeaweb.org/articles?id=10…
@joshgans Thank you for sharing this! I guess the next paper would be about "AI in tenure decisions", here is an early OR paper on the topic: pubsonline.informs.org/doi/10.1287/op…
OPEN SOURCED IT: github.com/AKMessi/smartie
IT REALLY WORKED!! i asked codex gpt 5.5xhigh to build a smart screen recorder that has smart effects like auto zoom, cursor tracking, etc. i had to iterate a bit, but now it works really well, planning to open-source it for windows, linux (currently supports only linux),
Wonderful interview by @Tim_Roughgarden and @skominers with @Pmilgrom . Gets at the heart of how economics works. youtube.com/watch?v=y60fmz…
How can an LLM switch between low-, medium-, and high-effort reasoning? And how does an LLM learn to reason more or less? I put together a “little” article explaining how these effort levels are implemented at inference time and during training.
New Accepted articles are available for Production and Operations Management at journals.sagepub.com/toc/PAO/0/ja
New OnlineFirst articles are available for Production and Operations Management at journals.sagepub.com/toc/PAO/0/0
Production and Operations Management Vol. 35, No. 8, August 1, 2026 is now available online. @subodha0
Big news: New Fed Chair Kevin Warsh just announced the members of his 5 tasks forces. It's a mix of academics, central bankers, and biz/tech leaders. Also a mix of left and right leaning
After 18 months of writing, coding, and experimenting, Build a Reasoning Model (From Scratch) is finally out! My first copies just arrived! 📚 440 full-color pages. Inference scaling, reinforcement learning, and distillation from scratch.
this is the weirdest possible demo of a very serious idea: objects are about to explain themselves. OpenAI took a normal houseplant and gave it a camera, memory, optional moisture/light sensors, and realtime voice. so now you can ask the plant how it's doing, and it can answer from its actual environment. here's how it works: 1. webcam sees the plant 2. ChatGPT analyzes the image 3. optional cheap sensors check soil moisture + light 4. the app saves recent observations 5. realtime voice turns the whole thing into a conversation so "are you thirsty?" becomes: it looks at the plant, checks the soil, remembers recent history, and answers in plain english the plant is a small example but there are infinite use-cases if you think about it
Our plants are chatty. Yours can be too. Give your plants a voice with our build guide: github.com/openai/plantta…
New research: Is AI making employers view labor as more of a commodity? In a large online labor market, we find that post-ChatGPT, clients place less weight on signals of human capital and more on price when hiring.
Jordan's former teammates seem to burn bridges long after their playing days are over. LeBron, on the other hand, has built relationships that extend far beyond basketball. Teammates, coaches, and peers continue to support and respect him years later. That says a lot about the man behind the game. 🏀
BREAKING: GLM-5.2 is now 1st on Design Arena. With an Elo of 1360, GLM-5.2 has jumped ahead of the now unavailable Claude Fable 5. And it's open weights. This is an improvement of 4 positions and 27 Elo points to achieve one of the highest Elo scores in our code categories since Design Arena started. Huge congratulations to the @Zai_org on the release!
CONFIRMED: Uber has now capped agentic coding tools at $1,500 per employee per month per tool after it blew through the entire annual budget in 4 months. Under CTO Praveen Neppalli Naga, reports say 10X of the blown output were driven by code commits from developers in India.
Uber blew through its entire annual AI budget in a single quarter, according to CEO Dara Khosrowshahi who said developers in India are driving 10X the code commits they used to tricky Indian programmers blowing up AI budgets to make sure they don’t get fired.
Today, the Stanford @DigEconLab launches the AI Economic Indicators, a new platform for tracking how AI is reshaping work, productivity, adoption, and the economy. 1/6
Andrej Karpathy spent 2h showing how he actually uses AI day to day he's a co-founder of OpenAI and led AI at Tesla, so when he shows how he works, it’s worth watching and the whole session is just him telling the machine what he wants in simple terms, like he's briefing a coworker watch what's actually happening the entire time: > he describes the task in normal words > it goes off and does the work > he glances at the result and nudges it with one more sentence that's the whole skill, and you've had it since you learned to talk the only gap between that and a worker that runs on its own is handing that sentence a schedule and the tools to act check his work, then build the version that keeps working when you stop
The @UChi_Economics rule is 2 minutes per slide. Mike Golosov also added that each slide should have at most four bullets. I found this rule to only be viable at @UChi_Economics . Audiences show a wide range of interaction, most way below the Uchicago level. So I follow this rule: - each slide should have only one idea, at most four bullets, and a bullet can never break a line - if I know that the audience wants interaction, I follow the Uchicago gold standard - if I am uncertain, I do one minute per slide and adjust during the talk.
Presenter slide decks in a four-paper session with 22 minutes per talk: • 49 slides • 36 slides • 32 slides • 40 slides
@aaryan_kakad Very useful! Will give it a try and let you know
Adam Elmachtoub @Adam235711
3K Followers 2K Following Associate Professor of Industrial Engineering and Operations Research @Columbia @CUSEAS @DataSciColumbia @DAP__Lab
Maxime Cohen @maxccohen
874 Followers 641 Following Scale AI Chair Prof @McGillU | Chief AI Scientist @CIUSSS_COMTL | Advisor in AI @ivadolabs | Ex @GoogleAI @MIT PhD
Tinglong Dai @TinglongDai
2K Followers 2K Following Ferrari Professor of Business @JohnsHopkins @JHUCarey @JHU_HBHI @HopkinsDSAI @JHUNursing @IDIESJHU; VP @INFORMS ✍🏻 AI, Supply Chains, & Healthcare
Qiuping Yu @QiupingYu
471 Followers 376 Following Associate Professor,@Georgetown, @msbgu, PhD @NorthwesternU - Business Analytics, Consumer Behavior, Labor Economics, Socially Sustainable Operations
Serguei Netessine @snetesin
3K Followers 427 Following Senior Vice Dean and Professor @Wharton, author The Risk-Driven Business Model, speaker on innovation, consultant, angel investor
kamalini ramdas @ramdask
785 Followers 564 Following Deloitte Chair in Innovation & Entrepreneurship, Professor of Management Science & Operations, London Business School
Mohamad Soltani @MohamadSoltani_
364 Followers 315 Following Assistant Professor of Operations Management @UAlbertaBiz, @UAlberta. Tweeting about #healthcare, #operations, #analytics, and #education.
Hitesh @Hitesh3p
0 Followers 30 Following
Auyon Siddiq @auyonomous
425 Followers 553 Following Associate Professor @UCLAAnderson. Market design, digital platforms, AI. @UCBerkeley PhD.
Constantine Caramanis @cmcaram
1K Followers 537 Following Professor at UT Austin, Research in Machine Learning/AI and Optimization. Always rethinking teaching (English & Greek). Aspiring accordion street musician.
ObenCeryan @obenc
52 Followers 366 Following Research & teaching @BayesBSchool; @UMich grad; Dynamic pricing, revenue management, management science, operations research
Elena Duran 🌹 @Edu2099533
29 Followers 444 Following
Yiota S @yiota_p
1 Followers 6 Following
Florian Buetow @bytetweets
210 Followers 541 Following Hi, I am Florian, AI Engineering Lead | Evals and Guardrails for Agents | Ex-Reddit Ads ML Platform | Petabyte-scale IR/NLP Systems | Blog 👇
Nelson Zepeda @NelsonZepeda733
162 Followers 2K Following Scaling data stacks and exploring LLM integrations. Deep in the world of Snowflake and Claude. Here to share what works, what breaks, and what’s next in data.
MD. Jewel Mia @JewelMia005
3 Followers 205 Following Graduate & Research Assistant at The University of Barishal. Senior Project Manager at NayTechs, Bangladesh.
Colin chen @ccshh996
0 Followers 56 Following
David Bell @davidbnz
9K Followers 2K Following Co-Founder and Consumer Investor, Author of Location Is (Still) Everything, #DigitalEconomy Speaker, Researcher, #Kiwi
Queathoud @QueathoudRBt
85 Followers 2K Following
Sasiofr @Sasiofrdfpsr
15 Followers 452 Following
YUSHENG CUI @EthanYSChui
2 Followers 38 Following
curryrice @anotheranalyst_
145 Followers 2K Following
Dara @dara_tourt
10 Followers 7K Following
Marios Papachristou @papachristoum
669 Followers 1K Following Assistant Professor at @ASU @WPCareySchool PhD from Cornell CS ex: @msftresearch, @twitter/@x, @ntua
buba juwara @bubajuwara17064
210 Followers 7K Following Actually life in Africa is not easy especially for the needy but we keep and praising God for better days I believe bo condition is permanent
Alireza Javadian Sabe... @ArjSabet
349 Followers 735 Following Inc. Postdoctoral Scholar @KnowLab, @UChicago | Fellow @DigEconLab, @StanfordHAI | Ph.D. in Information Science | Prev. @PittDINS, @PoliMi, @datascience_mi
Luke Byrne @Lukezo
1K Followers 4K Following Aspire fellow, musician and journalist - drums, guitars and storytelling. Likes loud music, cycling, running and Liverpool. Dislikes - mayonnaise.
Benjamin Manning @BenSManning
3K Followers 923 Following Phd Student @MIT | Economics, AI, & Behavioral Science | Research: https://t.co/DvYK0d3Hsb
Islam Zekry @IslamZekri
587 Followers 2K Following Group CFO - Commercial International Bank (Egypt)
BINYAMIN BASHEER BIN @cpbinyamin
16 Followers 133 Following
Ebusiness@Newcastle @ebusncl
907 Followers 3K Following Research in ebusiness, ecommerce, emarketing, and egovernment
Sunny Miura @XueAkemi_
799 Followers 4K Following If I see someone without a smile, I give them one of mine. 🇵🇭/🇯🇵 #Music #Foodie #Traveler #Sporty #Coffee
旧颜 @hyx_jiuyan
10 Followers 138 Following
Jun Li @Jun_W_Li
152 Followers 161 Following Associate Professor, Ross School of Business, University of Michigan
Weitong Zhang @WeitongZhang
1K Followers 3K Following Assistant Professor @UNC | CS Ph.D. @UCLA | Ex-intern @nvidia |@amazon fellow
Piaras @PiarasFahey
0 Followers 2 Following
Leon Leng @LeonLeng5
264 Followers 2K Following PhD @UW | Alumni @UCBerkeley @cuhksz | AI, Traveling Salesman
Léonce B. ANO @Leonceano
372 Followers 2K Following Program manager & Governance | Researcher & Consultant | AI x Value Chain Innovation |
Armin @ArminMokhtarii
62 Followers 559 Following a normal who's toiling relentlessly to transcend into an outlier
Neha Sharma @NSharma_001
122 Followers 206 Following Assistant Professor @Wharton @Penn || Interested in Market Design and Platforms || Likes “||”
Panos Ipeirotis @ipeirotis
4K Followers 449 Following Professor at @NYUStern. #ai #datascience #crowdsourcing I have opinions.
Dalith Steiger @DalithSteiger
109K Followers 101K Following Co-Founder of #swisscognitive #cognitivevalley - all #Switzerland companies using #AI and #cognitive #technologies united in one network – Why Wait? Act Now!
a&*QF@7t!4u@V @S3eee29Oys13mK6
16 Followers 224 Following
Subhajit Chakraborty @subhajitc
112 Followers 107 Following Research interests: Operations and Quality Management in services, including health care
Sylvia Lu @SylviaLuUk
1K Followers 822 Following Chartered Engineer & NED | Telecoms, Chipset, Tech, 5G, IoT, Industry 4.0, Metaverse | Strategy, Innovation | Cambridge Executive MBA & Oxford Uni Alumni
Giuliano Sansone, Ph.... @giulianosansone
1K Followers 3K Following Assistant Prof at @ucddublin of #management. Past: Assistant Prof @vsecz | PhD @PoliTOnews | Visiting PhD @MITSloan
Chris Knight @ChrisKnight
35K Followers 34K Following Artist & Free Spirit; Aerial Photography/Drones, Long-Exposure/Aurora/Aviation & Nature Photography.
Entrepreneurship Jour... @Entrepr61399735
1K Followers 4K Following Academy of Entrepreneurship Journal (AEJ) is a peer reviewed open access journal affiliated to Allied Business Academy. Whats app: +441518081136
Adam Elmachtoub @Adam235711
3K Followers 2K Following Associate Professor of Industrial Engineering and Operations Research @Columbia @CUSEAS @DataSciColumbia @DAP__Lab
Maxime Cohen @maxccohen
874 Followers 641 Following Scale AI Chair Prof @McGillU | Chief AI Scientist @CIUSSS_COMTL | Advisor in AI @ivadolabs | Ex @GoogleAI @MIT PhD
John Horton @johnjhorton
19K Followers 3K Following Mind and Hand. Co-founder of @ExpectedParrot (YC F25)
Ethan Mollick @emollick
376K Followers 592 Following Professor @Wharton studying AI. New book, Co-Existence, coming October 20. Preorder here: https://t.co/hsDYf1xU9K Substack: https://t.co/UIBhxu4bgq
Ben Golub @ben_golub
70K Followers 3K Following econ prof @NorthwesternU, co-founder at https://t.co/RSvoCbDuGc studying networks past: @Harvard | @Stanford'12 | @Caltech '07
Tinglong Dai @TinglongDai
2K Followers 2K Following Ferrari Professor of Business @JohnsHopkins @JHUCarey @JHU_HBHI @HopkinsDSAI @JHUNursing @IDIESJHU; VP @INFORMS ✍🏻 AI, Supply Chains, & Healthcare
Florian Ederer @florianederer
55K Followers 2K Following Austrian 🇦🇹(&🇺🇸) Economist 📈 But definitely not an Austrian economist! @nberpubs | @ecgiorg | @cepr_org | @BUQuestrom
Scott Kominers @skominers
31K Followers 12K Following Market Design/Entrepreneurship Professor @HarvardHBS & Faculty Affiliate @Harvard Economics; Research @a16zcrypto; Editor @restatjournal; Econ @Quora; … | #QED
Qiuping Yu @QiupingYu
471 Followers 376 Following Associate Professor,@Georgetown, @msbgu, PhD @NorthwesternU - Business Analytics, Consumer Behavior, Labor Economics, Socially Sustainable Operations
Jason Hartline @jasondhartline
2K Followers 426 Following Prof at @NorthwesternCS & @NUEconomics (by courtesy). Theory of computation and online markets. Building the #academicmetaverse with @TheVirtualChair.
Serguei Netessine @snetesin
3K Followers 427 Following Senior Vice Dean and Professor @Wharton, author The Risk-Driven Business Model, speaker on innovation, consultant, angel investor
kamalini ramdas @ramdask
785 Followers 564 Following Deloitte Chair in Innovation & Entrepreneurship, Professor of Management Science & Operations, London Business School
Abhishek Nagaraj @abhishekn
12K Followers 6K Following Associate Prof @berkeleyhaas, NBER RA. Dad to 2 girls. he/him/his. Interested in using tech, AI and data to drive progress. Using ideas as my maps.
Michal Feldman @MichalFeldman9
3K Followers 254 Following Professor of Computer Science, @TelAvivUni | @AcmSIGecom Chair | Research areas: Econ&CS, Algorithmic Game Theory, Market Design
Soroush Saghafian @Soroush_Saghaf
2K Followers 2K Following Associate Professor @Harvard | Founder & Director @PIASLab | #AnalyticsScience | #Healthcare | #MachineLearning | #AI | #DecisionMaking | #PublicPolicy | #ORMS
Jackie Ng Lane @jackienlane
891 Followers 352 Following Asst. Prof @HarvardHBS, Former postdoc @LISHarvard, curious about all things to do w/ finding high-impact innovations using humans + AI. 🇨🇦🇺🇸
ACM SIGecom @AcmSIGecom
2K Followers 2 Following ACM SIGecom encourages research and advanced applications at the interface between economics and computer science. See you at EC'26 #ACMEC26!
EconCS Preprints & Bl... @econ_cs
1K Followers 0 Following Posts from arXiv https://t.co/EStePwyRHm and EconCS blogs, maintained by @kiragoldner. Halting activity in the coming weeks; suggesting migration to bluesky.
Virtual Market Design... @VMDSeminar
1K Followers 94 Following Team: Olivier Bos, @FuggerNicolas, @PatrickLahr, Daniil Larionov & Marion Ott. Former organizers: V. Gretschko, H. Mass, M. Pollrich & N. Szech († 16.08.2023).
Matt Clancy @mattsclancy
10K Followers 2K Following Abundance and Growth Fund Program Director at @coeff_giving. Creator of https://t.co/dYDulHqlOs. See https://t.co/6EvVGkycU7 for more.
Epoch AI @EpochAIResearch
50K Followers 0 Following Investigating the trajectory of AI for the benefit of society.
Sebastian Raschka @rasbt
494K Followers 1K Following ML/AI research engineer. Ex stats professor. Author of "Build a Large Language Model From Scratch" (https://t.co/O8LAAMRzzW) & reasoning (https://t.co/5TueQKx2Fk)
Ole Lehmann @itsolelehmann
158K Followers 3K Following I cover AI + robotics. Helping business owners win in the AI era. eu/acc supporter, dad, techno-optimist
Alp Sungu @Alpsungu
1K Followers 2K Following Assistant Prof @Wharton I study the interplay between technology, policy and society.
Design Arena @DesignArena
22K Followers 14 Following World's first benchmark for real-world visuals with 5.6M+ creators and counting. Made by @intelligence_ai
Benjamin Netanyahu - ... @netanyahu
4.3M Followers 33 Following ראש הממשלה ויו״ר הליכוד https://t.co/jjO4V91WG1
Constantine Caramanis @cmcaram
1K Followers 537 Following Professor at UT Austin, Research in Machine Learning/AI and Optimization. Always rethinking teaching (English & Greek). Aspiring accordion street musician.
Investing visuals @InvestingVisual
117K Followers 117 Following See clearly. Invest independently. 10 years in tech | +350% since 2023 | Not financial advice | For much more content: https://t.co/oVrgIdpSx6
The Greek Analyst @GreekAnalyst
92K Followers 6K Following Updates and commentary on startups, economics, geopolitics, political risk, global markets and tech. Focus on Greece & Europe.
Claude @claudeai
1.7M Followers 2 Following Claude is an AI assistant built by @anthropicai to be safe, accurate, and secure. Talk to Claude on https://t.co/ZhTwG8dz3D or download the app.
Aniket Panjwani @aniketapanjwani
7K Followers 347 Following I teach agentic coding to economists || PhD Economics Northwestern || ~9k on YouTube
@Axiomofmind ⚡ @axiomofmind
136 Followers 551 Following AI tinkering: openclaw, image gen, video gen, robots Local AI rig: RTX PRO 6000, RTX PRO 5000, RTX PRO 4500, 2x RTX 5090
Brian Roemmele @BrianRoemmele
485K Followers 44K Following we can only see what we think is possible...
scott cunningham @causalinf
53K Followers 6K Following Economics professor paying it forward with 55 burgers, 55 fries, 55 tacos, 55 pies, 55 Cokes, 100 tater tots, 100 pizzas, 100 tenders, 100 meatballs
Peter Steinberger �... @steipete
573K Followers 2K Following Polyagentmorous ClawFather. Came back from retirement to mess with AI and help a lobster take over the world. @OpenClaw🦞 + @OpenAI
David Senra @davidsenra
221K Followers 115 Following Conversations with the greatest living founders.
OpenClaw🦞 @openclaw
543K Followers 25 Following Personal AI that actually does things. Your agent, your machine, your rules. Now a 501(c)(3) non-profit foundation — open and independent, forever. 🦞
Prof @TheProfInvestor
132K Followers 280 Following Canada's most followed trading voice 15 years of market execution Now decoding global macro, equities, risk & market psychology. Frameworks over forecasts
Jesse Genet @jessegenet
58K Followers 3K Following Startup builder (prev @lumi) turned family builder, currently vibe coding on my breaks from homeschooling four tots
This Week in Startups @twistartups
101K Followers 624 Following Your thrice weekly deep dive into startups, markets, & tech | Hosted by @jason and @lons We're hiring! Apply: [email protected] or [email protected]!
Alex @AlexanderTw33ts
19K Followers 1K Following making something agents want founder of @rentahumanx
Igor Babuschkin @ibab
111K Followers 888 Following CEO & Co-Founder @river_ai_inc. Previously @xAI, Research & Engineering
Nicola McClafferty @NikkiMcClaff
3K Followers 1K Following Partner @MoltenVentures (FKA Draper Esprit). 3 kiddos. Dublin, London 👩🏻💻☘️
Pliny the Liberator �... @elder_plinius
234K Followers 1K Following ⊰•-•⦑ latent space steward ❦ prompt incanter 𓃹 hacker of matrices ⊞ breaker of markov chains ☣︎ ai danger researcher ⚔︎ bt6 ⚕︎ architect-healer ⦒•-•⊱
Aditya Agarwal @adityaag
74K Followers 383 Following General Partner @SPC, Co-Founder @Bevel_Health | Ex: Early Eng @facebook, CTO @Dropbox, Board @Flipkart | Optimist, Builder, Dad
Andy Hall @ahall_research
12K Followers 3K Following Political economy of superintelligence @AnthropicAI Writing at https://t.co/K0BfKKhwDe Prof @StanfordGSB, Senior Fellow @HooverInst (On Leave)
Aaryan Kakad @aaryan_kakad
4K Followers 408 Following 19 | self taught ML guy | building ai agents | documenting the process | sharing what I learn
Ai2 @allen_ai
86K Followers 447 Following Breakthrough AI to solve the world's biggest problems. › Join us: https://t.co/MjUpZpKPXJ › Newsletter: https://t.co/k9gGznstwj
tom cunningham @testingham
11K Followers 3K Following Economics & AI @ @METR_Evals (ex-openai) https://t.co/FZobuYjdOc
OpenAI Developers @OpenAIDevs
394K Followers 1 Following Official updates for developers building with Codex & the OpenAI Platform • Service status: https://t.co/kZwnwdYYEq
Yiota S @yiota_p
1 Followers 6 Following
Sebastien Bubeck @SebastienBubeck
84K Followers 1K Following I work on AI at OpenAI. Former VP AI and Distinguished Scientist at Microsoft.
Zoe Wang @zoewangai
1K Followers 1K Following Co-Founder @OpenRead_HQ | sharing AI & trending research
Pierre | fresh market... @aipierrepierre
443 Followers 256 Following Get all the market signals delivered to your inbox👇
Florian Buetow @bytetweets
210 Followers 541 Following Hi, I am Florian, AI Engineering Lead | Evals and Guardrails for Agents | Ex-Reddit Ads ML Platform | Petabyte-scale IR/NLP Systems | Blog 👇
Isomorphic Labs @IsomorphicLabs
63K Followers 82 Following Solve all disease. Developing and applying frontier AI to unlock deeper scientific insights, faster breakthroughs, and life-changing medicines.
Disaster News @Top_Disaster
979K Followers 357 Following Disaster News is your source for news from across the world. Please Support my channel. DM for credit/removal/submission
Mechanize @MechanizeWork
14K Followers 1 Following We build environments and evals for training and evaluating frontier coding agents.
Joshua Gans @joshgans
20K Followers 759 Following Professor at the Rotman School of Management, University of Toronto. Chief Economist of Creative Destruction Lab https://t.co/a9ZbnBauCF
Anthropic @AnthropicAI
1.6M Followers 2 Following We're an AI safety and research company that builds reliable, interpretable, and steerable AI systems. Talk to our AI assistant @claudeai on https://t.co/FhDI3KQh0n.
Ιαν @Giannis726523
3K Followers 122 Following
Demis Hassabis @demishassabis
1.7M Followers 178 Following Nobel Laureate. Co-Founder & Chair @GoogleDeepMind; Chief Scientist of Alphabet. Founder & CEO @IsomorphicLabs. Building the future...
near @nearcyan
245K Followers 1K Following allow yourself to introspect and realize what was lost: twitter will never return to what it once was. close your phone; think about how you now spend your life























