【推荐1】When consuming information, we try to acquire more signals and less noise. We feel like the more information we consume the more signals we receive. While this is probably true on an absolute basis, Nassim Taleb argues in the book Antifragile that it is not true on a relative basis. As you consume more data and the ratio (比率) of noise to signals increases, you know less about what’s going on and you are likely to cause more unintentional trouble.

The supply of information to which we are exposed under modernity is transforming humans from a calm person to a neurotic (神经质的) one. For the purpose of our discussion, the first person only reacts to real information, and the second largely to noise. The difference between the two will show us the difference between noise and signals. Noise is what you are supposed to ignore; signals are what you need to heed.

In science, noise is a generalization beyond the actual sound to describe random information that is totally useless for any purpose, and that you need to clean up to make sense of what you are listening to. You can use and take advantage of noise and randomness, but noise and randomness can also use and take advantage of you, particularly with the data you get on the Internet or through other media. The more frequently you look at data, the more noise you are likely to get, and the higher the noise-to-signal ratio is.

Say you look at information on a yearly basis—the changes you see will all be large ones. The ratio of signals to noise is about one to one—this means that about half the changes are real improvements or degradations, and the other half come from randomness. But if you look at the very same data on a daily basis, the composition would change to 95 percent noise and 5 percent signals, and the changes you see daily will certainly be small.

【推荐2】Each year, more than 27 million U.S. and Canadian kids get to school by bus. Most of those buses run on diesel (柴油) fuel, which give out pollution that riders can take in. Pollution levels can be several times higher inside a diesel school bus than outside it. Why? Pollution can leak in from the floor or blow in through windows.

A U.S. government program started in 2012 offered schools’ money spent on cleaner school buses but not all schools could get it. Five years later, emissions from buses in the winning districts fell. And a year after getting new buses, student attendance had improved in those districts. For an average district of 10, 000 students, about six more students attended ‘school each day’ in the winning districts, compared to the losing districts. Winning schools with higher rates of bus-riding kids had an average of 14 more students in class each day. And winning districts that replaced the oldest school buses? They had an average of 45 more students in school each day.

Those numbers may sound small, but they add up. And school attendance matters for student achievement. Almost 3 million U. S. kids ride school buses more than 20 years old. If U. S. school districts had replaced all of those older buses, there would have been 1. 3 million fewer student absences each year.

There might be other reasons for better attendance. For example, maybe kids preferred new buses. However, the most-likely reason for fewer student absences was better health. A study done on adults showed that a brief exposure to diesel emissions reduced “network connectivity” in the brain. In other studies, such network-connectivity changes have been linked to worsened memory and mental tasks. A Washington State program upgraded pollution controls in old diesel buses. Afterward, fewer kids were hospitalized in those districts than in schools without bus upgrades.

Almost all U. S. school districts can apply for the program. But schools in low-income areas, in tribal areas and, in rural areas will get priority. Kids in these areas tend to face the most health risks from older buses.

【推荐2】Plastic recycling is a hot topic. But what’s the real face behind it? You diligently sort your rubbish; you dutifully wash your plastic containers; then everything gets thrown in a landfill or in the ocean anyway. According to one analysis, only 9% of all plastic ever made has likely been recycled. Here’s the kicker: the companies making all that plastic have spent millions on advertising campaigns lecturing us about recycling while knowing full well that most plastic will never be recycled.

A new investigation by National Public Radio (NPR) and the Public Broadcasting Service (PBS) reports that the large oil and gas companies that manufacture plastics have known for decades that recycling plastic was unlikely to ever happen on a broad scale because of the high costs involved. “They were not interested in putting any real money or effort into recycling because they wanted to sell raw material,” Larry Thomas, former president of one of the plastic industry’s most powerful trade groups, told NPR. There is a lot more money to be made in selling new plastic than reusing the old stuff. But, in order to keep selling new plastic, the industry had to clean up its wasteful image. “If the public thinks that recycling is working, then they are not going to be so concerned about the environment,” Thomas noted.

We have been successfully convinced that people start pollution and people can stop it and that if we just recycle more, the planet will be OK. To some degree, that is right: there must be a level of personal responsibility when it comes to the climate emergency. We all have to do our part. But individual action is a tiny drop in a heavily polluted ocean. We need systematic change to make a real difference. And, more than anything, we need to change what we value.