Tag Archives: scientific literacy

Correlation is Not Causation: “Fat is Catching” Theory Exposed

“Fat is catching” theory exposed

Their study was reported to have shown that you can “catch” obesity from having fat friends and that obesity is so contagious, it can be spread long-distance by email and instant messaging. Even healthcare professionals, who didn’t understand the etiology of true obesity or how statistics can be misused, failed to detect the implausibility of “second-hand obesity.” In fact, some doctors became so enamored with the new “science of networking” they believed it should be a new medical specialty: network medicine.

Jason M. Fletcher, Ph.D., assistant professor at the Yale School of Public Health in New Haven, Connecticut, along with Boston economist, Ethan Cohen-Cole, Ph.D., designed an ingenious study. They selected conditions that no one would seriously believe were spread by social networking and online friendships: height, headaches and acne. They then applied the same standard statistical methods used in Christakis and Fowler’s social networking research to “find” that acne, height and headaches have the same “social network effect.”

As they explained, patterns of association among people can lead to correlations in health conditions between friends that are not caused by direct social network effects at all.

There is a need for caution when attributing causality to correlations in health outcomes between friends using non-experimental data. Confounding is only one of many empirical challenges to estimating social network effects.

Excellent reminder of the risks of analyzing data for correlations. We continue to, far to often, fail to interpret data properly. Both authors of the study, received PhD’s from the University of Wisconsin-Madison which strengthens my belief that it is teaching students well (just kidding).

Also another example of the scientific inquiry process where scientists challenge the conclusions drawn by other scientists. It is a wonderful system, even if confusing and not the clean idea so many have of how science works.

Related: Correlation is Not CausationSeeing Patterns Where None ExistsStatistics for Experimenters500 Year FloodsPlaying Dice and Children’s NumeracyThe Illusion of UnderstandingAll Models Are Wrong But Some Are UsefulData Doesn’t Lie But People Can Draw Faulty Conclusions from Data

Fund Teacher’s Science Projects

With donorschoose.org teachers submit project proposals for materials or experiences their students need to learn. These ideas become classroom reality when concerned individuals, whom we call Citizen Philanthropists, choose projects to fund.

Such as: Budding Scientists Need Basics!!! – “My students need 9 hands-on science equipment such as graduated cylinders, magnifying glasses, and vivid photographic books about weather and life cycles so they can experience science first-hand. The cost of this proposal is $386”

Hands On Science! – “My students need a human body model, a skeleton model, a skull model, 2 microscopes, beakers and graduated cylinders. The cost of this proposal is $1,060”

Eyes On Observation! – “My students need 4 Brock Magiscopes. The cost of this proposal is $688”

Let’s Rock the Rocks – “My students needs 2 complete sets of classroom Rock, Fossil & Mineral Collections and a Rock & Soil Activity Tub for science. The cost of this proposal is $351”

You can target high poverty schools, if you wish. If you want to help make a difference in the science literacy of the USA go ahead and find a project you want to help fund and make a donation. Or if you are a teacher, add a project for others to fund.

Related: Hands-on High School Engineering Education in MinnesotaThe Economic Consequences of Investing in Science EducationBuilding minds by building robotsEducation Resources for Science and Engineering

Poor Reporting and Unfounded Implications

Correlation is not causation. And reporting of the form, “1 time this happened” and so I report it as though it is some relevant fact, is sad. Take any incident that happened and then state random traits you want to imply there is some relevant link to (blue eyes, red hair, people that watch IT Crowd, people that bought a banana yesterday, tall, overweight, did poorly in math…) and most people will know you are ignorant.

Looking at random data people will find patterns. Sound scientific experimentation is how we learn, not trying to find anything that support our opinions. Statistics don’t lie but ignorant people draw faulty conclusions from data (when they are innumerate – illiteracy with mathematical concepts).

It’s not what the papers say, it’s what they don’t by Ben Goldacre

On Tuesday the Telegraph, the Independent, the Mirror, the Express, the Mail, and the Metro all reported that a coroner was hearing the case of a toddler who died after receiving the MMR vaccine, which the parents blamed for their loss. Toddler ‘died after MMR jab’ (Metro), ‘Healthy’ baby died after MMR jab (Independent), you know the headlines by now.

On Thursday the coroner announced his verdict: the vaccine played no part in this child’s death. So far, of the papers above, only the Telegraph has had the decency to cover the outcome.

Measles cases are rising. Middle class parents are not to blame, even if they do lack rhetorical panache when you try to have a discussion with them about it.

They have been systematically and vigorously misled by the media, the people with access to all the information, who still choose, collectively, between themselves, so robustly that it might almost be a conspiracy, to give you only half the facts.

Science education is important. Even if people do not become scientists, ignorance of scientific thinking is dangerous. The lack of scientific literacy allows scientifically illiterate leaders to make claims that are lacking scientific merit. And results in people making poor choices themselves, due to their ignorance.

Related: Bad Science blog by Ben GoldacreIllusion of Explanatory DepthIllusions – Optical and Otherposts on vaccinesposts on scientific literacy

Compounding is the Most Powerful Force in the Universe

A talking head with some valuable info. I remember my father (a statistics professor) getting me to understand this as a small child (about 6 years old). The concept of growth and mathematical compounding is an important idea to understand as you think and learn about the world. It also is helpful so you understand that statistics don’t lie but ignorant people can draw false conclusions from limited data.

It is unclear if Einstein really said this but he is often quoted as saying “compounding is the most powerful force in the universe.” Whether he did or not, understanding this simple concept is a critical component of numeracy (literacy with numbers). Also quoted at times as: “Compound interest is the eighth wonder of the world.” My guess is that people just find the concept of compounding amazing and then attribute quotes about it to Einstein.

I strongly encourage you to watch at least the first 2 segments (a total of 15 minutes). And then take some time and think. Take some time to think about compounding in ways to help you internalize the concepts. You can also read his book: The Essential Exponential For the Future of Our Planet by Albert Bartlett.

Related: Playing Dice and Children’s NumeracySaving for Retirement (compound interest)Bigger Impact: 15 to 18 mpg or 50 to 100 mpg?Sexy MathThe Economic Benefits of Math

The Science of Gardening

Photo of a bee by Justin Hunter

The Science of Gardening

Linda Chalker-Scott, an associate professor at Washington State University, is the author of The Informed Gardener and producer of the column “Horticultural Myths.” In The Truth About Garden Remedies: What Works, What Doesn’t, and Why, Jeff Gillman, associate professor at the University of Minnesota, is just as rational and informative

Do go ahead and dig in soil improvements, Chalker-Scott advises, for vegetable gardens or annual flowerbeds, in which nutrients need replacing yearly. But there’s really no need to dig organic amendments—manure and peat moss, etc.—into landscapes that are permanent. Treat those plantings of trees and shrubs as if they were forest ecosystems, not agricultural fields—wood chips and decaying leaves on top, no tilling-in of fertilizer.

It must drive both authors nuts to hear people say, “I’m an organic gardener. I never use chemicals.” Everything on earth is composed of chemicals.

The last line calls to mind the recent Royal Society of Chemistry attempt to reclaim the word chemical from the advertising and marketing industries: £1,000,000 for 100% chemical free material. A good example for our scientific literacy posts.

Photo by Justin Hunter.

Related: Curious Cat Cool Garden ConnectionsResearchers Learn What Sparks Plant GrowthSave Money on Food with a GardenThe Science Barge

Understanding the Evolution of Human Beings by Country

graphic showing countries understanding of evolution I recently wrote about evolution and scientific literacy. The graph on the left shows the percentage of the population that understands evolution is a core scientific principle. The graph based on data from 2005 for 34 countries.

Blue indicates those that know that “human beings, as we know them, developed from earlier species of animals.”
Yellow are those that are unsure
Red are those that don’t know that it is true

Evolution Less Accepted in U.S. Than Other Western Countries, Study Finds, from National Geographic News:

A study of several such surveys taken since 1985 has found that the United States ranks next to last in acceptance of evolution theory among nations polled. Researchers point out that the number of Americans who are uncertain about the theory’s validity has increased over the past 20 years.

The United States is is second to last place in this question of scientific literacy with only 40% of the population knowing the truth. The USA was between Cyprus and Turkey in this measure of understanding of scientific knowledge. The most knowledgeable countries have about twice the rate of knowledgeable respondents (with nearly 80% knowing).

Related: Scientific Illiteracy by Country (the USA managed to stay in the top 10 for overall scientific literacy rate of 8th graders in 2003) – Understanding Evolution (University of California at Berkeley)Scientifically IlliteracyRetrovirusesDNA Repair ArmyMassive Project Will Reveal How Humans Continue to EvolveGene Study Finds Cannibal PatternNigersaurusRare Chinese Mountain Cat

Playing Dice and Children’s Numeracy

My father, Willaim Hunter, a professor of statistics and of Chemical Engineering at the University of Wisconsin, was a guest speaker for my second grade class (I think it was 2nd) to teach us about numbers – using dice. He gave every kid a die. I remember he asked all the kids what number do you think will show up when you roll the die. 6 was the answer from about 80% of them (which I knew was wrong – so I was feeling very smart).

Then he had the kids roll the die and he stood up at the front to create a frequency distribution of what was actually rolled. He was all ready for them to see how wrong they were and learn it was just as likely for any of the numbers on the die to be rolled. But as he asked each kid about what they rolled something like 5 out of the first 6 said they rolled a 6. He then modified the exercise a bit and had the kid come up to the front and roll the die on the teachers desk. Then my Dad read the number off the die and wrote on the chart 🙂

This nice blog post, reminded me of that story: Kids’ misconceptions about numbers — and how they fix them

in the real study, conducted by John Opfer and Rober Siegler, the kids used lines with just 0 and 1000 labeled. They were then given numbers within that range and asked to draw a vertical line through the number line where each number fell (they used a new, blank number line each time). The figure above represents (in red) the average results for a few of the numbers used in the study. As you can see, the second graders are way off, especially for lower numbers. They typically placed the number 150 almost halfway across the number line! Fourth graders perform nearly as well as adults on the task, putting all the numbers in just about the right spot.

But there’s a pattern to the second-graders’ responses. Nearly all the kids (93 were tested) understood that 750 was a larger number than 366; they just squeezed too many large numbers on the far-right side of the number line. In fact, their results show more of a logarithmic pattern than the proper linear pattern.

Science and Engineering in Politics

Politics of engineering by Patrick Mannion, EE Times:

Engineering interests historically haven’t been at the forefront of the political debate, at least not compared with those of, say, farming, law or health care. But given the importance of the technological advances that engineers help effect and the need to maintain our competitive edge in a rapidly changing global environment, that situation needs to change, and fast.

Then came word of the $25 billion being handed to farmers in yet another subsidy, loudly denounced by some as welfare for the wealthy. I’m not going to get into the right or wrong of the subsidies–but I am amazed at the ability of agribusiness to get them at all. It shows the power of the farm lobby. Ditto for pharmaceuticals, HMOs, lawyers, “big oil” and so on. It underscores the relative political weakness of the engineering community.

If the science and engineering community are not well represented to our representatives the interests of the science and engineering community will get short changed. Especially since so few politicians in the USA have even a basic understanding of science and the scientific method. And a very small percentage have any advanced degrees in science and engineering fields or work experience in them. That being said the political arena is much like a tar pit: that is it is difficult to interact with without becoming entangled in a big mess. And it is not as though the scientific and engineering community are even close to unified but still the impact of political decisions is very significant and science and engineering leaders need to be heard.

China’s Economic Science Experiment – China’s 9 most senior government official are all engineers (in 2006 – I am not sure now):

When China’s leaders meet with Hu each week in Beijing’s government district, Zhongnanhai, they could spend hours discussing cables, switches, tool-making machines and control devices. That’s because every one of them has a degree in engineering. The president himself, the son of a tea merchant from Jiangsu Province, trained to build hydroelectric power stations, while the others hold degrees in electrical engineering, metallurgy and geology.

Related: Larry Page on Marketing ScienceThe A to Z Guide to Political Interference in ScienceDiplomacy and Science ResearchOpen Access LegislationProposal to Triple NSF Graduate Research Fellowship AwardsScience Interview with John EdwardsProposed Legislation on Science and EducationHouse Testimony on Engineering EducationGermany’s Science ChancellorNanotechnology Investment as Strategic National Economic PolicySingapore Supporting Science ResearchersFarming Without Subsidies in New Zealand

People Have More Bacterial Cells than Human Cells

Humans Carry More Bacterial Cells than Human Ones

All the bacteria living inside you would fill a half-gallon jug; there are 10 times more bacterial cells in your body than human cells

The infestation begins at birth: Babies ingest mouthfuls of bacteria during birthing and pick up plenty more from their mother’s skin and milk—during breast-feeding, the mammary glands become colonized with bacteria. “Our interaction with our mother is the biggest burst of microbes that we get,”

there are estimated to be more than 500 species living at any one time in an adult intestine, the majority belong to two phyla, the Firmicutes (which include Streptococcus, Clostridium and Staphylococcus), and the Bacteroidetes (which include Flavobacterium).

probiotics – dietary supplements containing potentially beneficial microbes – have been shown to boost immunity. Not only do gut bacteria “help protect against other disease-causing bacteria that might come from your food and water,” Huffnagle says, “they truly represent another arm of the immune system.”

But the bacterial body has made another contribution to our humanity – genes. Soon after the Human Genome Project published its preliminary results in 2001, a group of scientists announced that a handful of human genes – the consensus today is around 40 – appear to be bacterial in origin.

How cool is science? Very, I think 🙂

Related: Tracking the Ecosystem Within UsBeneficial BacteriaEnergy Efficiency of DigestionLarge Number of Bacteria on our SkinWhere Bacteria Get Their GenesAmazing Science: Retroviruses

Open Source: The Scientific Model Applied to Programming

xo-laptop: On the Open-Sourcing of Business – interesting post worth reading, though I disagree with some points:

There is no obligation to “give back” anything, though it often makes sense to participate in the community based on a particular open-source project. However, that is a strategic decision for you to make. Your sole obligation is to respect the license terms.

There is a difference between your sole legal obligation and your sole obligation. I agree legally all you are obliged to do is comply with the legal requirements. That does not mean that is your sole obligation. I don’t see any problem making money in efforts involving open source efforts but I do believe that as that happens an obligation (perhaps not legal but real none-the-less) grows to give back to the community (Google’s summer of code is a great example of giving back). Most open source efforts require that any additions you make to the software be given back to the community (those involved in open souce know this, I add this just for the information of those not familiar with open source practices). Legal obligations are the minimum you can be forced to do, not the only obligations one has. Great quote (emphasis mine):

I think the best is one I have often seen expressed by Linus Torvalds, and it was one of the explanations I gave in a talk to the New York City Linux User Group in a talk in December, 1999.

Simply put, free and open-source software is just the scientific model applied to programming: free sharing of work open collaboration; open publication; peer review; recognition of the best work, with priority given to the first to do a meaningful new piece of work; and so forth. As a programmer, it is the best arena in which to work. There are no secrets; the work must stand on its own.

Another great post on this topic: What Business Can Learn from Open Source.

Related: Open Source for LEGO MindstormsYoung Scientists Design Open-Source Program at NASAOpen-Source BiotechPublishers Continue to Fight Open Access to Science