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Scientists find that coin tosses aren't 50/50. Here's how you can get an advantage

The age-old method isn't as fair and practical as we originally thought.

coin toss, math, probability, science, science news, Persi Diaconis
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Coin tosses aren't 50/50 like we've been led to believe

Settling things by coin toss has been around for centuries. The ancient Romans called it “‘Heads or Ships.” Britains of the Middle Ages knew it as “Cross or Pile.” Throughout history, this game of chance was believed to be a fair, unbiased way to settle a dispute, choose which team goes first in a sports game and make decisions.

And the thought behind this makes sense. After all, there are only two sides to a coin, making the odds for each outcome an even 50/50. It doesn’t get more even than that.

However, a team of scientists, led by former magician and American mathematician Persi Diaconis, have discovered that this age-old method isn’t as evenly split as we believed. And there's even a way to slightly cheat the odds to your advantage.


Diaconis made a name for himself by studying (and debunking) randomness, one of his more famous feats being determining how many times a deck of cards must be shuffled in order to truly mix up the deck. Even as a teenager, he exposed how casino scammers would shave their dice to improve their chances against customers.


When it comes to coin games, Diaconis has long argued that while it’s “pretty close to fair,” it’s definitely not 50/50. Especially when a little wobble is introduced into the toss, which increases the chance that the coin will land on the same side it started.


A group of scientists set out to test Diaconis' findings and their study, currently in preprint, revealed that coins did indeed land on the same side they were tossed from around 51 percent of the time.

“According to the [Diaconis] model, precession causes the coin to spend more time in the air with the initial side facing up,” they wrote. “Consequently, the coin has a higher chance of landing on the same side as it started (i.e., ‘same-side bias’).”

The study recorded 350,757 coin flips, carried out by 48 people using 46 different currencies. In the end, there turned out to be a 50.8 percent chance of the coin showing up the same side it was tossed from.

They also found that some tossers showed a strong same-side bias while others had none at all, indicating that coin tosses may come down to the tosser, ever so slightly.

While this might not seem like a huge margin, the advantage becomes clear when you put into a betting scenario. "If you bet a dollar on the outcome of a coin toss (i.e., paying 1 dollar to enter, and winning either 0 or 2 dollars depending on the outcome) and repeat the bet 1,000 times, knowing the starting position of the coin toss would earn you 19 dollars on average,” the team explained.

"This is more than the casino advantage for 6 deck blackjack against an optimal-strategy player, where the casino would make 5 dollars on a comparable bet, but less than the casino advantage for single-zero roulette, where the casino would make 27 dollars on average."

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You could also use physics to your advantage, not just probability. Diaconis also proved that the head side of a coin is a tiny bit heavier than its tails counterpart, causing it to land on tails more often. Especially when it comes to Lincoln Memorial pennies.

So next time you are fighting with a loved one over whose turn it is to do the dishes, you can still settle it with a coin toss. Just conceal the starting position first. Or take a peak a use this hard earned knowledge. No judgement.

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Her groundbreaking theory on the origin of life was rejected 15 times. Then biology proved her right.

Lynn Margulis had the audacity to challenge Darwin. And we're lucky she did.

lynn margulis, lynn margulis symbiosis, biology, scientific breakthroughs, darwin, darwinism, women in science
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A photo of Lynn Margulis.

Throughout her prolific and distinguished career, biologist Lynn Margulis made several groundbreaking contributions to science that we take for granted as common knowledge today. For example, she championed James E. Lovelock’s “Gaia concept,” which posited that the Earth self-regulates to maintain conditions for life.

But by far, her most notable theory was symbiogenesis. While it was first written off as “strange” and “aesthetically pleasing” but “not compelling,” it would ultimately prevail, and completely rewrite how we viewed the origin of life itself.

In the late 1960s, Margulis wrote a paper titled "On the Origin of Mitosing Cells," that was quite avant-garde. In it, she proposed a theory: that life evolved through organisms merging together to become inseparable.

In essence, cooperation is the driver of life, not competition and domination. This directly went against Darwin’s “survival of the fittest” principle that was considered gospel in scientific circles. Margulis’ paper was rejected by fifteen journals before getting accepted into the Journal of Theoretical Biology.

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Time would be on Margulis’ side, however. By the late ‘70s and early ‘80s, research proved that the two major building blocks of plants and animals, chloroplasts and mitochondria were at one time independent bacteria. This solidified the fact that on a biological level, connection trumps autonomy for longevity. And now that fact is written in textbooks, with no real story of the adversity it overcame to get there.

While it is customary for most new scientific theories to be met with criticism, especially those that completely shift the current narrative, many have noted that sexism played a key part in Margulis’ initial lack of acceptance. On more than one occasion, she herself had hinted that women were seen as mothers and wives first, and scientists second. She recalled that while married to fellow scientist Carl Sagan that “Carl would finish his sentence, unperturbed” while she was expected to “handle all the duties of a 1950s housewife, from washing dishes to paying the household bills.”

And yet, Margulis would have other ideas that were controversial that had nothing to do with her gender. Most famously, she did not believe that AIDS was caused by HIV, and instead believed it was cause by a syphilis-causing type of bacteria, despite there already being decades of research proving otherwise. That view was seen as an endorsement of AIDS denialism, which undermined prevention and treatment effort. Then later in life, Margulis became a vocal proponent of 9/11 conspiracy theories suggesting government involvement the in Twin Towers attacks.

And yet, perhaps this is one of those “you gotta take the good with the bad” situations. Margulis’ inherent contrarian nature gave us both these unfounded, even harmful stances, in addition to entirely new paradigms that altered our understanding of life itself.

And if nothing else, it illuminated the need for science to include multiple points of view in order to unlock the truth. It seems life is, after all, about coming together.

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Most Americans agree bed sheets get 'gross' after 35 days. Experts say it's much sooner.

This is how often you should wash your sheets, according to experts.

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The rest of your bedding doesn't need to be washed as often.

There's nothing better than hopping into bed with clean sheets. But let's be honest: washing your sheets can be a pain. From stripping the bed to putting sheets back on post-washing, it's a chore. But you may want to re-think how often you should be washing your bed sheets.

According to a survey of 1,000 Americans conducted by Mattress Advisor, the average time between sheet changings or washings in the U.S. is 24 days—or every 3 1/2 weeks, approximately. The same survey revealed that 35 days is the average interval at which unwashed sheets are "gross."

If that sounds about right to you, prepare to be shocked. According to experts, you should be washing your sheets *a lot* sooner than that for hygiene reasons.

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How often should you wash your sheets?

Hint: It's a lot more frequent than 24 days.

While there is no definitive number of days or weeks, most experts recommend swapping out used sheets for clean ones every week or two.

Dermatologist Alok Vij, MD told Cleveland Clinic that people should wash their sheets at least every two weeks, but probably more often if you have pets, live in a hot climate, sweat a lot, are recovering from illness, have allergies or asthma, or if you sleep naked.

We shed dead skin all the time, and friction helps those dead skin cells slough off, so imagine what's happening every time you roll over and your skin rubs on the sheets. It's normal to sweat in your sleep, too, so that's also getting on your sheets. And then there's dander and dust mites and dirt that we carry around on us just from living in the world, all combining to make for pretty dirty sheets in a fairly short period of time, even if they look "clean."

Maybe if you shower before bed and always wear clean pajamas you could get by with a two-week sheet swap cycle, but weekly sheet cleaning seems to be the general consensus among the experts. The New York Times consulted five books about laundry and cleaning habits, and once a week was what they all recommend.

Sorry, once-a-monthers. You may want to step up your sheet game a bit.

sheets, bed sheets, clean sheets, how often should you wash your sheets, how often should you wash your bed sheets Experts agree that this is how often you should wash your bed sheets.Photo credit: Canva

What about the rest of your bedding? Blankets and comforters and whatnot?

Olivia Parks, Owner + Lead Organizer at Nola Organizers, told Upworthy that duvet covers should be cleaned every week or so.

"Even though the cover protects the insert, the insert still collects body odor, sweat, body oils from lotions or other body products, crumbs if you eat in your bed, dog hair or cat hair, and more," she explained.

Somewhere between the Gen X and Millennial eras, young folks stopped being about the top sheet life, just using their duvet with no top sheet. If that's you, wash that baby once a week. If you do use a top sheet, you can go a couple weeks longer on the duvet cover.

For blankets and comforters and duvet inserts, Sleep.com says every 3 months. And for decorative blankets and quilts that you don't really use, once a year washing will suffice.

What about pillows? Pillowcases should go in with the weekly sheet washing, but pillows themselves should be washed every 3 to 6 months. Washing pillows can be a pain, and if you don't do it right, you can end up with a lumpy pillow, but it's a good idea because between your sweat, saliva and skin cells, pillows can start harboring bacteria.

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Baking soda absorbs moisture and or odor and breaks down any residue that builds up! If you have allergies you should be doing this more often! #cleaning #lifehack #tiktokshopcybermonday #tiktokshopblackfriday #mattressvacuumcleaner

Finally, how about the mattress itself? Home influencers on TikTok can often be seen stripping their beds, sprinkling their mattress with baking soda, brushing it into the mattress fibers and then vacuuming it all out. Architectural Digest says the longer you leave baking soda on the mattress, the better—at least a few hours, but preferably overnight. Some people add a few drops of essential oil to the baking soda for some extra yummy smell.

If that all sounds like way too much work, maybe just start with the sheets. Pick a day of the week and make it your sheet washing day. You might find that climbing into a clean, fresh set of sheets more often is a nice way to feel pampered without a whole lot of effort.

This article originally appeared two years ago. It has been updated.

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Stanford researchers find a single question could be the key to changing someone's mind

Curiosity goes a lot further than we might think.

discussion, debate, disagreement, conversation, communication, curiosity
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How do you get someone to open their minds to another perspective?

The diversity of humanity means people won't always see eye to eye, and psychology tells us that people tend to double down when their views are challenged. When people are so deeply entrenched in their own perspectives they're refusing to entertain other viewpoints, what do we do?

Frequently, what we do falls into the "understandable but ineffective" category. When we disagree with someone because their opinion is based on falsehoods or inaccurate information, we may try to pound them with facts and statistics. Unfortunately, research shows that generally doesn't work. We might try to find different ways to explain our stance using logic and reasoning, but that rarely makes a dent, either. So often, we're left wondering how on Earth this person arrived at their perspective, especially if they reject facts and logic.

According to Stanford researchers, turning that wondering into an actual question might be the key.

discussion, debate, disagreement, conversation, communication, curiosity Questions are more effective than facts when it comes to disagreements.Photo credit: Canva

The power of "Tell me more."

Two studies examined how expressing interest in someone's view and asking them to elaborate on why they hold their opinion affected both parties engaged in a debate. They found that asking questions like, "Could you tell me more about that?” and ‘‘Why do you think that?" made the other person "view their debate counterpart more positively, behave more open-mindedly, and form more favorable inferences about other proponents of the counterpart’s views." Additionally, adding an expression of interest, such as, ‘‘But I was interested in what you’re saying. Can you tell me more about how come you think that?” not only made the counterpart more open to other viewpoints, but the questioner themselves developed more favorable attitudes toward the opposing viewpoint.

In other words, genuinely striving to understand another person's perspective by being curious and asking them to say more about how they came to their conclusions may help bridge seemingly insurmountable divides.

discussion, debate, disagreement, conversation, communication, curiosity Asking people to elaborate leads to more open-mindedness.Photo credit: Canva

Stanford isn't alone in these findings. A series of studies at the University of Haifa also found that high-quality listening helped lower people's prejudices, and that when people perceive a listener to be responsive, they tend to be more open-minded. Additionally, the perception that their attitude is the correct and valid one is reduced.

Why curiosity works

In some sense, these results may seem counterintuitive. We may assume that asking someone to elaborate on what they believe and why they believe it might just further entrench them in their views and opinions. But that's not what the research shows.

Dartmouth cognitive scientist Thalia Wheatley studies the role of curiosity in relationships and has found that being curious can help create consensus where there wasn't any before.

“[Curiosity] really creates common ground across brains, just by virtue of having the intellectual humility to say, ‘OK, I thought it was like this, but what do you think?’ And being willing to change your mind,” she said, according to the John Templeton Foundation.

discussion, debate, disagreement, conversation, communication, curiosity Curiosity can help people get closer to consensus. Photo credit: Canva

Of course, there may be certain opinions and perspectives that are too abhorrent or inhumane to entertain with curious questions, so it's not like "tell me more" is always the solution to an intractable divide. But even those with whom we vehemently disagree or those whose views we find offensive may respond to curiosity with more open-mindedness and willingness to change their view than if we simply argue with them. And isn't that the whole point?

Sometimes what's effective doesn't always line up with our emotional reactions to a disagreement, so engaging with curiosity might take some practice. It may also require us to rethink what formats for public discourse are the most impactful. Is ranting in a TikTok video or a tweet conducive to this shift in how we engage others? Is one-on-one or small group, in-person discussion a better forum for curious engagement? These are important things to consider if our goal is not to merely state our case and make our voice heard but to actually help open people's minds and remain open-minded in our own lives as well.

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A girl's pet pig ate her homework. Teachers were stunned when mom sent them video proof.

"Okay, I have to admit this is a first for me!"

pigs, pets, homework, school, teachers, kids, dog ate my homework, excuses, funny, humor
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An Arizona girl claimed "My pig ate my homework!" Luckily, she had proof.

Believe it or not, "the dog ate my homework" excuse is over 100 years old. The first known anecdote involving a dog eating important documents came about around 1905. A professor was later recorded in 1929 writing, "It is a long time since I have had the excuse about the dog tearing up the arithmetic homework," suggesting the phrase had been around for some time.

In the century since, teachers the world over have heard every variation of excuse about why a student can't turn in their homework. But, in 2026, we may have fortuitously stumbled on a new one most teachers have never dreamed of.

Jacey Tinsley, a mom from Arizona, recently posted a story to social media that has to be seen to be believed. In the now viral post, she explains that her daughter Taylee was unable to turn in her homework for multiple subjects... because their pet pig ate it.

Yes, the Tinsleys have racked up quite a following on social media documenting life with their three mini-pigs, so it is certainly in the realm of possibility that one of the pigs could have gotten into Taylee's homework.

But would the teachers buy it?

Luckily, Tinsley was able to catch the whole thing on video via indoor Ring cam. In the footage, their pig Polly is caught red-handed snatching the backpack off of the counter, dragging it to the floor, and rifling through it—destroying several papers in the process. Tinsley took the initiative to email her daughter's teachers and school administrators with the indisputable photographic evidence.

Jacey Tinsley took full accountability for her daughter's missing work. "If/when you see any work that's partially eaten/chewed, that is 100% on us, not Taylee," she confessed.

Then, she hoped for the best.

The school staffers had no choice but to accept Jacey's ludicrous tale, and they got quite a kick out of it, too.

Taylee's principal was first to reply: "Okay, I have to admit this is a first for me!! I'm trying not to laugh hysterically..."

The science teacher chimed in next: "This is a first time in my teacher career to hear this and I find it hilarious."

The math teacher was a person of few words: "Oh my goodness, that is so funny."

Over two million people viewed the reel on Instagram and TikTok combined. Commenters were delighted by the ridiculous footage and had plenty of their own hard-to-believe stories of lost homework:

"I turned in homework once that was half eaten by my rabbits but all the answers weren't eaten so I got an A"

"That happened with my piggy she ate three page, so I sent a picture of our piggy Then the damn teacher wanted me to bring her to show and tell her"

"Had a classmate who brought in his homework that was literally eaten by his dog. My teacher thought it was so funny that he displayed the chewed up paper on his wall"

"My baby sister ate my homework once. I wish I was joking"

"My dog ate my homework which was a book I picked to read and it was about lying and saying that your dog ate your homework. I told my teacher and got yelled at so my Dad had to come in with the torn up book to prove I wasnt lying"

If there's anything to learn from the massive response to Tinsley's post, it's that, sometimes, the dog really does eat your homework. And if not the dog, then the rabbit, cat, or even pig.

Pigs can make terrific pets in the right home. They are surprisingly intelligent, playful, affectionate, and can be trained to do many of the tricks and tasks dogs can do.

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Pigs can, however, be quite destructive. Because they're so smart, any hint of boredom can drive them into a frenzy of activity; a favorite activity of many pigs is rooting. Rooting is when they use their powerful snout to push and dig at the ground—or whatever items happen to be around (like a backpack that smells like yesterday's lunch). It's an instinctual behavior that calms them and helps them find snacks.

Taylee got lucky this time that the whole incident was caught on camera. "The pig ate my homework," doesn't seem like the kind of excuse that's going to fly more than once without proof.

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'Remarkable' UPS driver runs into burning home to save 101-year-old woman

"I just did what I thought was right."

ups driver, ups, hero, house fire, elderly woman, orange county, california, local news, good news, ktla
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A delivery driver with a determined expression; a house on fire.

Fate often tests our courage at the most unexpected times. For UPS driver Willy Esquivel, that moment came on January 15 while he was completing a delivery in Orange County, California.

According to KTLA, Esquivel was on his routine route in Santa Ana when he noticed neighbors attempting to smother a blaze coming from the condo of Ann Edwards, a 101-year-old woman who lives alone.

Esquivel wasted no time entering the smoke-filled building to rescue Edwards, who seemed "very disoriented" and reluctant to leave. Nevertheless, Esquivel "picked her up and carried her safely outside," according to KTLA and a statement from the Orange County Fire Authority (OFCA).

A video posted on the OFCA's X account showed just how thick the smoke was pouring from Edwards' condo as firefighters arrived. The OFCA also acknowledged the resourceful neighbors who aided in the rescue.

"At the same time, the neighbors used fire extinguishers to knock down the kitchen fire," the OCFA wrote on X. "One of them, a roofer by trade, grabbed his ladder, climbed to the roof, and used a garden hose to spray water into the kitchen vent."

Thankfully, while Edwards was taken to the hospital, she was expected to make a full recovery. Her son, Rick, told KTLA that he was grateful to Esquivel for "sticking with her and getting her out of there."

As for Esquivel, rather than seeing himself as a hero, he told KTLA that he was "just a UPS driver who was in the right place at the right time."

"I just did what I thought was right," he added. "At the end of the day, she's someone's mother, someone's grandmother, great-grandmother."

- YouTube www.youtube.com

Moments like this rarely announce themselves ahead of time. They unfold in the middle of ordinary days, on familiar streets, while people are simply doing their jobs or moving through their routines. Delivery drivers like Esquivel travel through neighborhoods every day, often unnoticed, yet uniquely positioned to sense when something is wrong. On this day, being present and paying attention made all the difference.

Just as striking as Esquivel's bravery was the way neighbors instinctively sprang into action. Without hesitation, they grabbed fire extinguishers, ladders, and garden hoses, each contributing whatever they had in the moment. Together, their quick thinking and collaboration helped prevent an even greater tragedy.

"A remarkable outcome made possible by quick action, teamwork, and people looking out for one another in a moment of need," the OCFA wrote on X.

It's easy to assume someone else will step in. That it's not your fight. That it's not your responsibility. Heroism requires the opposite mindset. And at a time when the world can feel increasingly short on that quality, this story is a refreshing reminder that yes, there are still good people out there willing to help, even when it means helping complete strangers while on the job.

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