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Jevon’s Paradox

Jevon's Paradox is the counterintuitive idea that improvements in fuel efficiency tend to increase, rather than decrease, overall fuel use. In 1865, William Stanley Jevons, a British economist, observed that despite significant improvements in coal efficiency in steam engines, total coal consumption actually rose. Rather than saving fuel, efficiency made coal-powered energy more economical, driving increased industrial use. This observation became known as Jevon's Paradox. Modern Examples of Jevon's Paradox Though first identified towards the end of the Industrial Revolution, Jevon's Paradox is still highly relevant today, particularly in discussions around energy efficiency, sustainability, and technology. Fuel-efficient cars – When vehicles become more fuel-efficient, the cost per mile driven decreases. As a result, people tend to drive more, offsetting the efficiency gains. AI and computing power – Advances in AI and computing efficiency reduce the cost of processing power, leading to increased overall usage of AI models and cloud computing. Battery technology – More efficient batteries lead to the proliferation of battery-powered devices rather than reducing energy consumption. Water-saving devices – Low-flow showerheads and toilets may save water per use, but in some cases, they lead to longer showers or more frequent flushing. Lighting — Though LED lights are vastly more efficient than their predecessors, we are continually finding new ways to use our low-wattage lights that we had never dreamed of before. Household appliances – In her book More Work for Mother, Ruth Cowan addresses the ironies of household appliances, such as washing machines and vacuum cleaners, and how improvements in efficiency often led to more work through more frequent washing, not less. This tendency is sometimes referred to as the rebound effect, where changes in behaviour partially or fully cancel out expected energy or resource savings. Jevon's Paradox and AI With the rise of AI and automation, Jevon's Paradox is playing out again in new ways: Computational efficiency – Though AI models are becoming more efficient—DeepSeek a case in point—the demand for AI-generated content, large language models, and deep learning applications is growing rapidly. Automated processes – Instead of reducing overall workloads, automation often leads to more tasks being completed rather than fewer tasks needing to be done. Cloud computing – More efficient data centres have not reduced overall energy use because the demand for cloud services and machine learning applications continues to skyrocket. Can Jevon's Paradox Be Overcome? Understanding Jevon's Paradox can help in designing better policies and strategies to ensure efficiency gains lead to real reductions in resource consumption. Some approaches include: Carbon pricing and regulation – Ensuring that energy efficiency is paired with policies that discourage excessive consumption. (see Goodhart's Law) Shifting behaviors – Encouraging individuals and businesses to actively reduce energy use, rather than simply taking advantage of efficiency improvements. Technology with constraints – Implementing smart grid systems, time-based energy pricing, and consumption limits to prevent unchecked increases in demand. Jevon's Paradox reminds us that efficiency alone is not a guaranteed solution for reducing resource consumption. Instead, it often requires complementary policies, incentives, and behavior changes to make efficiency gains truly effective. Read more about Jevon's in the NYT. Related Ideas to Jevon's Paradox Also see: The Fifth Fuel: energy efficiency The Automation Paradox – The better the machines get, the more we struggle when they fail Wishcycling — Hoping something can be recycled Save some landfill with reusable diapers/nappies…Jevon's Paradox is the counterintuitive idea that improvements in fuel efficiency tend to increase, rather than decrease, overall fuel use. In 1865, William Stanley Jevons, a British economist, observed that despite significant improvements in coal efficiency in steam engines, total coal consumption actually rose. Rather than saving fuel, efficiency made coal-powered energy more economical, driving increased industrial use. This observation became known as Jevon's Paradox. Modern Examples of Jevon's Paradox Though first identified towards the end of the Industrial Revolution, Jevon's Paradox is still highly relevant today, particularly in discussions around energy efficiency, sustainability, and technology. Fuel-efficient cars – When vehicles become more fuel-efficient, the cost per mile driven decreases. As a result, people tend to drive more, offsetting the efficiency gains. AI and computing power – Advances in AI and computing efficiency reduce the cost of processing power, leading to increased overall usage of AI models and cloud computing. Battery technology – More efficient batteries lead to the proliferation of battery-powered devices rather than reducing energy consumption. Water-saving devices – Low-flow showerheads and toilets may save water per use, but in some cases, they lead to longer showers or more frequent flushing. Lighting — Though LED lights are vastly more efficient than their predecessors, we are continually finding new ways to use our low-wattage lights that we had never dreamed of before. Household appliances – In her book More Work for Mother, Ruth Cowan addresses the ironies of household appliances, such as washing machines and vacuum cleaners, and how improvements in efficiency often led to more work through more frequent washing, not less. This tendency is sometimes referred to as the rebound effect, where changes in behaviour partially or fully cancel out expected energy or resource savings. Jevon's Paradox and AI With the rise of AI and automation, Jevon's Paradox is playing out again in new ways: Computational efficiency – Though AI models are becoming more efficient—DeepSeek a case in point—the demand for AI-generated content, large language models, and deep learning applications is growing rapidly. Automated processes – Instead of reducing overall workloads, automation often leads to more tasks being completed rather than fewer tasks needing to be done. Cloud computing – More efficient data centres have not reduced overall energy use because the demand for cloud services and machine learning applications continues to skyrocket. Can Jevon's Paradox Be Overcome? Understanding Jevon's Paradox can help in designing better policies and strategies to ensure efficiency gains lead to real reductions in resource consumption. Some approaches include: Carbon pricing and regulation – Ensuring that energy efficiency is paired with policies that discourage excessive consumption. (see Goodhart's Law) Shifting behaviors – Encouraging individuals and businesses to actively reduce energy use, rather than simply taking advantage of efficiency improvements. Technology with constraints – Implementing smart grid systems, time-based energy pricing, and consumption limits to prevent unchecked increases in demand. Jevon's Paradox reminds us that efficiency alone is not a guaranteed solution for reducing resource consumption. Instead, it often requires complementary policies, incentives, and behavior changes to make efficiency gains truly effective. Read more about Jevon's in the NYT. Related Ideas to Jevon's Paradox Also see: The Fifth Fuel: energy efficiency The Automation Paradox – The better the machines get, the more we struggle when they fail Wishcycling — Hoping something can be recycled Save some landfill with reusable diapers/nappies

2 Dec 2018

Marchetti’s constant

Marchetti's constant is the idea that people throughout history have budgeted, on average, about an hour a day for travelling. Originally observed by Yacov Zahavi, it came from the observation that even as our means of transport sped up, instead of travelling less each day, we would just travel further. This leads to the conclusion that the size of our cities increases partly according to how efficiently we can travel in and out—they generally increase to a size that maintains about an hour of round-trip travel time. Cesare Marchetti observed that Greek villages and ancient walking cities, as marked by ancient city walls, tend to share a radius of about 2.5km. Walking at a typical 5km/hr makes a one-hour round-trip journey. He also pointed out that: “Even people in prison for a life sentence, having nothing to do and nowhere to go, walk around for one hour a day, in the open.” Unfortunately, if you live in London, the average round-trip seems to be an exception of 1h30. This is also known as the constant travel time budget hypothesis. Also see: Isochrones. It might be interesting to look at these according to transport method Our senses are built to take in information at human pace Image adapted from: Marchetti, C., 1994: Anthropological Invariants in Travel Behavior, Technological Forecasting and Social Change , 47 :75–88, Internal Publication, International Institute for Applied Systems Analysis.…Marchetti's constant is the idea that people throughout history have budgeted, on average, about an hour a day for travelling. Originally observed by Yacov Zahavi, it came from the observation that even as our means of transport sped up, instead of travelling less each day, we would just travel further. This leads to the conclusion that the size of our cities increases partly according to how efficiently we can travel in and out—they generally increase to a size that maintains about an hour of round-trip travel time. Cesare Marchetti observed that Greek villages and ancient walking cities, as marked by ancient city walls, tend to share a radius of about 2.5km. Walking at a typical 5km/hr makes a one-hour round-trip journey. He also pointed out that: “Even people in prison for a life sentence, having nothing to do and nowhere to go, walk around for one hour a day, in the open.” Unfortunately, if you live in London, the average round-trip seems to be an exception of 1h30. This is also known as the constant travel time budget hypothesis. Also see: Isochrones. It might be interesting to look at these according to transport method Our senses are built to take in information at human pace Image adapted from: Marchetti, C., 1994: Anthropological Invariants in Travel Behavior, Technological Forecasting and Social Change , 47 :75–88, Internal Publication, International Institute for Applied Systems Analysis.

25 Nov 2018

The Availability Heuristic illustration: Plane crashes, cold snaps, and winning lottery tickets are shown as examples of uncommon but widely reported events that might affect the significance we associate with them.

The availability heuristic (and bias)

The availability heuristic is a deceptively simple, almost too simple to notice, heuristic where we consider the likelihood of events by the ease with which relevant instances come to mind. In simple terms, things that we can easily recall or where we can think of examples, we generally consider as more important or more common than other things. A heuristic is a mental shortcut to solve a common problem. If we were asked to consider the divorce rate in the community, we might evaluate that by considering how many of our acquaintances are divorced. If none of your friends are divorced, you’re naturally less likely to think the divorce rate locally will be high. In many situations, it makes good sense to give credence to what you remember easily. However, in situations involving probabilities, in particular, the heuristic will lead us predictably astray such that more often I think of it as an availability bias — a predictable pattern of thought and behaviour leading to incorrect conclusions. So, the vividness of shark attacks causes us to overrate how likely they are to actually occur. Or we’re more likely to worry about lions than hippos, even though hippos kill more people each year than lions. Or the risk of being struck by lightning vs stuck by a car crossing a road. Or, the prevalence of violent crime on the news compared to the likelihood of you being a victim. Or the fact that it’s cold outside and yet the planet is gradually warming. Here’s a 1973 Kahneman and Tversky paper: Availability: A Heuristic for Judging Frequency and Probability…The availability heuristic is a deceptively simple, almost too simple to notice, heuristic where we consider the likelihood of events by the ease with which relevant instances come to mind. In simple terms, things that we can easily recall or where we can think of examples, we generally consider as more important or more common than other things. A heuristic is a mental shortcut to solve a common problem. If we were asked to consider the divorce rate in the community, we might evaluate that by considering how many of our acquaintances are divorced. If none of your friends are divorced, you’re naturally less likely to think the divorce rate locally will be high. In many situations, it makes good sense to give credence to what you remember easily. However, in situations involving probabilities, in particular, the heuristic will lead us predictably astray such that more often I think of it as an availability bias — a predictable pattern of thought and behaviour leading to incorrect conclusions. So, the vividness of shark attacks causes us to overrate how likely they are to actually occur. Or we’re more likely to worry about lions than hippos, even though hippos kill more people each year than lions. Or the risk of being struck by lightning vs stuck by a car crossing a road. Or, the prevalence of violent crime on the news compared to the likelihood of you being a victim. Or the fact that it’s cold outside and yet the planet is gradually warming. Here’s a 1973 Kahneman and Tversky paper: Availability: A Heuristic for Judging Frequency and Probability

17 Nov 2018

What is the Pomodoro Technique in 3 steps: plan your tasks, complete one 25-minute pomodoro with a 5-minute break, and repeat for four pomodoros before taking a longer break.

The Pomodoro Technique: Stay Focused and Get More Done

The Pomodoro Technique® is a simple and effective time management method that helps you stay focused and get your tasks done. It's named after a kitchen timer shaped like a pomodoro (Italian for tomato) and is great for studying, working, and managing ADHD. Here's how it works: How to Use the Pomodoro Technique 1. Plan Your Tasks Decide what you want to accomplish and estimate how many pomodoros (usually 25-minute focus sessions) you'll need for each task. 2. Do One Pomodoro Set a timer for 25 minutes. Focus entirely on your task until the timer rings, then take a 5-minute break. Avoid multitasking or distractions during this time. That's one pomodoro.` 3. Repeat for Four Pomodoros After completing four pomodoros, take a longer break of about 30 minutes to recharge. Why Use the Pomodoro Technique? The Pomodoro Method is popular because it's simple and effective. It's particularly helpful for: Improved Focus: Short, timed sessions make it easier to stay on task. Better Time Management: By breaking your day into pomodoros, you can plan and track progress easily. Studying: Great for staying productive during long study sessions. ADHD: Some say it helps manage focus and provide structured breaks. Tips for Success Some tips: Protect your pomodoro from distractions— make sure you spend the full 25 minutes on your task. If people want things, tell them you'll get back to them after your pomodoro. Properly break in your breaks — no sneaky working. Step away, move around, or grab a snack. It’s flexible, not rigid — If you need longer or shorter times, that's OK. It's about what helps you focus. You only need a timer, but some simple Pomodoro technique apps can help, too. I like this nice one with a bear and natural sounds while you work: Bear Focus Timer. Francesco has also created Pomodoro timers, which you can run on the web or your computer. The Pomodoro Technique ® was created and named by Francesco Cirillo. He explains that it came to him very simply. He was struggling to stay on task as a student and challenged himself to stay productive for 2 minutes using a timer he had in the kitchen. It worked. He then tried extending the length of the focus session. An hour was too much, 10 minutes too little, and the sweet spot was right around 25 minutes. The kitchen timer was a pomodoro. More Productivity Ideas Looking for other ways to stay productive? Here are my other favourite sketches on productivity: Productivity tools and techniques Forcing Function Public Commitment Pledge Commitment Devices Implementation Intentions Checkbox To Do lists Eat the Frog The Eisenhower Matrix: Important/Urgent Thinking About Productivity Manager Time, Maker Time The First Draft is Always Perfect The Power of Streaks Goldilocks Tasks Flow Looking to get started on a new project or a daring step? Here are my sketches on Getting Started. About this site Welcome to Sketchplanations! If this is your first time here, I've packed this site with simple sketches that explain ideas in clear and engaging ways. From productivity tips to insights on science, writing, human behaviour, and wellbeing, it's becoming, I hope, a treasure trove of visual explanations. If you like the Pomodoro Technique, I think you might also like the other sketches of my toolkit for life in my book Big Ideas Little Pictures, which even has a lovely review from Bill Gates.…The Pomodoro Technique® is a simple and effective time management method that helps you stay focused and get your tasks done. It's named after a kitchen timer shaped like a pomodoro (Italian for tomato) and is great for studying, working, and managing ADHD. Here's how it works: How to Use the Pomodoro Technique 1. Plan Your Tasks Decide what you want to accomplish and estimate how many pomodoros (usually 25-minute focus sessions) you'll need for each task. 2. Do One Pomodoro Set a timer for 25 minutes. Focus entirely on your task until the timer rings, then take a 5-minute break. Avoid multitasking or distractions during this time. That's one pomodoro.` 3. Repeat for Four Pomodoros After completing four pomodoros, take a longer break of about 30 minutes to recharge. Why Use the Pomodoro Technique? The Pomodoro Method is popular because it's simple and effective. It's particularly helpful for: Improved Focus: Short, timed sessions make it easier to stay on task. Better Time Management: By breaking your day into pomodoros, you can plan and track progress easily. Studying: Great for staying productive during long study sessions. ADHD: Some say it helps manage focus and provide structured breaks. Tips for Success Some tips: Protect your pomodoro from distractions— make sure you spend the full 25 minutes on your task. If people want things, tell them you'll get back to them after your pomodoro. Properly break in your breaks — no sneaky working. Step away, move around, or grab a snack. It’s flexible, not rigid — If you need longer or shorter times, that's OK. It's about what helps you focus. You only need a timer, but some simple Pomodoro technique apps can help, too. I like this nice one with a bear and natural sounds while you work: Bear Focus Timer. Francesco has also created Pomodoro timers, which you can run on the web or your computer. The Pomodoro Technique ® was created and named by Francesco Cirillo. He explains that it came to him very simply. He was struggling to stay on task as a student and challenged himself to stay productive for 2 minutes using a timer he had in the kitchen. It worked. He then tried extending the length of the focus session. An hour was too much, 10 minutes too little, and the sweet spot was right around 25 minutes. The kitchen timer was a pomodoro. More Productivity Ideas Looking for other ways to stay productive? Here are my other favourite sketches on productivity: Productivity tools and techniques Forcing Function Public Commitment Pledge Commitment Devices Implementation Intentions Checkbox To Do lists Eat the Frog The Eisenhower Matrix: Important/Urgent Thinking About Productivity Manager Time, Maker Time The First Draft is Always Perfect The Power of Streaks Goldilocks Tasks Flow Looking to get started on a new project or a daring step? Here are my sketches on Getting Started. About this site Welcome to Sketchplanations! If this is your first time here, I've packed this site with simple sketches that explain ideas in clear and engaging ways. From productivity tips to insights on science, writing, human behaviour, and wellbeing, it's becoming, I hope, a treasure trove of visual explanations. If you like the Pomodoro Technique, I think you might also like the other sketches of my toolkit for life in my book Big Ideas Little Pictures, which even has a lovely review from Bill Gates.

10 Nov 2018

Mercator Projection illustration: shows the consequences of flattening out a spherical globe. Whilst it's a handy exercise for navigating and producing maps, it can inflate the size of land masses the in the north and the south. In a Mercator projection Greenland is comparable in size with Africa. In reality, it's much smaller.

The Mercator projection

All maps involve decisions. Whenever you compress real life onto something smaller and less detailed you have to choose what to keep in and what to leave out. And in the case of printing a map of the Earth, you have to figure out how to get something that is curved onto something that is flat, and this involves trade-offs and decisions as well. 3 dimensional space just doesn’t flatten to 2 dimensional paper without choices. In 1569 Gerardus Mercator created a map that brilliantly solved a pressing problem — that of being able to follow a straight line while sailing and it correspond to a straight line on the map. His map also did a good job of preserving the shape of countries. But to do this you have to stretch the areas at the top and bottom of the Earth. Because most of the land on Earth is in the Northern hemisphere, and because that land is generally further north than the land in the southern hemisphere is south, it has the effect of enlarging Northern countries such as Europe, the US and Canada, Scandinavia and Russia as compared to countries closer to the equator and in the Southern hemisphere. Most world maps you see are still similar to Mercator’s projection. In fact Google Maps desktop used it until just recently. It could well be that this distorts our worldview by emphasizing Northern countries in size and therefore importance. When I see a more size accurate Gall-Peters projection I have to say it’s hard to argue. The West Wing did this brilliantly. HT: Paul Lewis…All maps involve decisions. Whenever you compress real life onto something smaller and less detailed you have to choose what to keep in and what to leave out. And in the case of printing a map of the Earth, you have to figure out how to get something that is curved onto something that is flat, and this involves trade-offs and decisions as well. 3 dimensional space just doesn’t flatten to 2 dimensional paper without choices. In 1569 Gerardus Mercator created a map that brilliantly solved a pressing problem — that of being able to follow a straight line while sailing and it correspond to a straight line on the map. His map also did a good job of preserving the shape of countries. But to do this you have to stretch the areas at the top and bottom of the Earth. Because most of the land on Earth is in the Northern hemisphere, and because that land is generally further north than the land in the southern hemisphere is south, it has the effect of enlarging Northern countries such as Europe, the US and Canada, Scandinavia and Russia as compared to countries closer to the equator and in the Southern hemisphere. Most world maps you see are still similar to Mercator’s projection. In fact Google Maps desktop used it until just recently. It could well be that this distorts our worldview by emphasizing Northern countries in size and therefore importance. When I see a more size accurate Gall-Peters projection I have to say it’s hard to argue. The West Wing did this brilliantly. HT: Paul Lewis

3 Nov 2018

The Diderot Effect

The Diderot effect describes how new purchases can lead to a negative spiral of replacing possessions that no longer live up to the new standard. In a capitalist or consumerist society, it highlights the dangers of material possessions on ourselves and our finances. "Regrets on Parting with My Old Dressing Gown." The effect is named after 18th-century French philosopher Denis Diderot, who wrote the entertaining and unusually-titled essay "Regrets on Parting with My Old Dressing Gown." In the essay, Diderot relates how his possessions no longer seemed up to scratch after being given a flashy new scarlet dressing gown. Seeing this, he replaced his old straw chair with a leather one, a plank bookshelf with an inlaid armoire, a clay statue with a bronze statue, and so on. In the process, he emptied his carefully earned savings. His tale is an example of the Diderot Effect in action. What's more, Diderot complains that whereas he was the master of his old dressing gown, he became a servant to the new one, needing to guard it from his clumsiness, spills, or burns. Our possessions can begin to control us rather than us control them. New and Old Identities More generally, the effect also highlights that we surround ourselves with objects that fit our sense of identity. When we receive something that reflects a new, aspirational identity, rather than rejecting the new thing, we may find ourselves replacing our old objects and selves to fit the new. Sometimes, we may be excited about embracing a new identity. Clearing out items reflecting our old selves may be a blessing and reflect aspects of our lives we wish to leave behind. Yet it perhaps pays to consider whether it's driven by the products or ourselves—whether we're still the masters or whether they are. As I learned from Dev Patnaik, products are created by culture and create culture. Examples of the Diderot Effect Here are some examples of the Diderot Effect in action that I could relate to: Denis Diderot gradually replacing his possessions with fancier more expensive ones and becoming poor as a result. Replacing my hastily bought student furniture with smarter furniture for our own home. Adding a new smart painting to a wall causing you to take down your old music posters. A new pair of shoes causing me to reconsider the whole outfit. Notes Cultural anthropologist Grant McCracken introduced the Diderot Effect, which I learned about from James Clear's Atomic Habits. As I learned from Seth Godin's Akimbo podcast episode — The Deletionists, Diderot also played a key role in the development of the encyclopedia. The Diderot Effect appears in my book Big Ideas Little Pictures. Here's a translation of Denis Diderot's essay "Regrets for my Old Dressing Gown, or A warning to those who have more taste than fortune" Related Ideas The paradox of choice The Streisand effect Front stage, back stage The Paradise Paradox Sharpen the saw Enough molehillls make a mountain Implementation intentions…The Diderot effect describes how new purchases can lead to a negative spiral of replacing possessions that no longer live up to the new standard. In a capitalist or consumerist society, it highlights the dangers of material possessions on ourselves and our finances. "Regrets on Parting with My Old Dressing Gown." The effect is named after 18th-century French philosopher Denis Diderot, who wrote the entertaining and unusually-titled essay "Regrets on Parting with My Old Dressing Gown." In the essay, Diderot relates how his possessions no longer seemed up to scratch after being given a flashy new scarlet dressing gown. Seeing this, he replaced his old straw chair with a leather one, a plank bookshelf with an inlaid armoire, a clay statue with a bronze statue, and so on. In the process, he emptied his carefully earned savings. His tale is an example of the Diderot Effect in action. What's more, Diderot complains that whereas he was the master of his old dressing gown, he became a servant to the new one, needing to guard it from his clumsiness, spills, or burns. Our possessions can begin to control us rather than us control them. New and Old Identities More generally, the effect also highlights that we surround ourselves with objects that fit our sense of identity. When we receive something that reflects a new, aspirational identity, rather than rejecting the new thing, we may find ourselves replacing our old objects and selves to fit the new. Sometimes, we may be excited about embracing a new identity. Clearing out items reflecting our old selves may be a blessing and reflect aspects of our lives we wish to leave behind. Yet it perhaps pays to consider whether it's driven by the products or ourselves—whether we're still the masters or whether they are. As I learned from Dev Patnaik, products are created by culture and create culture. Examples of the Diderot Effect Here are some examples of the Diderot Effect in action that I could relate to: Denis Diderot gradually replacing his possessions with fancier more expensive ones and becoming poor as a result. Replacing my hastily bought student furniture with smarter furniture for our own home. Adding a new smart painting to a wall causing you to take down your old music posters. A new pair of shoes causing me to reconsider the whole outfit. Notes Cultural anthropologist Grant McCracken introduced the Diderot Effect, which I learned about from James Clear's Atomic Habits. As I learned from Seth Godin's Akimbo podcast episode — The Deletionists, Diderot also played a key role in the development of the encyclopedia. The Diderot Effect appears in my book Big Ideas Little Pictures. Here's a translation of Denis Diderot's essay "Regrets for my Old Dressing Gown, or A warning to those who have more taste than fortune" Related Ideas The paradox of choice The Streisand effect Front stage, back stage The Paradise Paradox Sharpen the saw Enough molehillls make a mountain Implementation intentions

28 Oct 2018

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