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Comment: Re:It is a start (Score 2) 233 233

Better idea - use sophisticated computer programmed learning + continuous testing. Since students are learning and continually being retested on the material, and the questions are rarely the same for two different students (or even the same student 10 minutes later), nearly all cheating other than just standing there and answering for the student becomes impossible or at least impractical - IOW actually continuously monitor the students progress and help them actually _learn_ instead of faking it.

Of course, the education establishment really doesn't want to know a student's real capability, as this would elicit questions of actual performance, and ability - completely politically incorrect.

Comment: Re:How to REALLY lie with statistics (Score 4, Interesting) 233 233

Cheating has been a serious problem among asian students at every grade level in Southern California, for at least two decades. Not only cheating but a variety of other ploys, such as harassing teachers into giving out extra credit assignments to those who pester them, which can be used to artificially increase their grades. (Extra credit improves grades more than poor test scores bring them down.)

Comment: Re:'Doctor'? So why spout mistruth? (Score 1) 573 573

According to Wikipedia, atmospheric levels of CO2 have ranged as high as 7000 ppm (during the Cambrian period), at which time the rate of plant growth was as high or higher than any other time in the history of life. Present levels are scarily close to the lowest ever found, 180 ppm during the last glaciation.'' So I think you have your facts wrong. There is also satellite data and associated research showing that today, the deserts are greening up more than any time in recent history, due entirely to increased CO2.

It seems to me that being only a factor of two greater than the 'iceball Earth' level, out of a range of almost a factor of 20, puts us at present in the bot tom of the range. The geometric mean of 7000 and 200 is about 1180, which seems to be a not-unreasonable number compared to the geological record. This may, of course, mean that Florida is a rather small island and Bangladesh will need to hire the Dutch to build dikes.

Comment: Re:Not only about temperature (Score 1) 573 573

And yet in previous epochs, atmospheric CO2 has ranged as high as 7000 ppm - more than 16 times the 'worst case' of 400 ppm presently under discussion. In fact, except during ice ages, it's been higher than the present value almost all the time. But the oceans were not (AFAIK) more acidic - or at least they had lots of life in them, including a majority of shelled creatures. If so, then perhaps the acidity (if it is actually occurring) may be a transition phenomenon.

Comment: Re:Golden Rice (Score 1) 573 573

I've always thought that, if you believe 'everyone' should live a certain way, then you should live that way. If you are correct, eventually others will follow. By extension, if you believe that humans are evil and should all die off, then be my guest, start the trend.

Comment: Re:Climate Engineering (Score 1) 573 573

I guess you've never heard about the intense growing season in Alaska, resulting in giant vegetables and other crops - 65 lb. cabbages feet in diameter. 24 hour sunlight has amazing effects on some plants. (Of course in some cases this natural phenomenon has been encouraged by selective breeding, etc. but that's beside the point.)

Also, increased CO2 has been shown to be a powerful plant growth stimulant.

Comment: Re:Climate Engineering (Score 1) 573 573

present-day economists pretty much agree that the 1930s depression would have lasted about two-three years if the Fed had not used a tight money policy, while the government used Keynesian methods to try to artificially induce growth with inefficient make-work and dependency programs. Both were wrong - one removes the incentives for businesses (and agencies) to alter their behavior, and the other removes the incentives for individuals to change their behavior, while both incentivize their respective groups to become dependent on government handouts. Prior to government interventions the hundred years prior had a number of short, sharp recessions that resolved themselves within three years. It is only since we've had government interventions that these long, drawn-out painful decades have become common.

Comment: Re:Claims should be easily verified (Score 1) 573 573

Reading your commen, I was inspired to do a bit of 'research' (aka googling). This from WIkipedia:

Carbon dioxide is well mixed in the Earth's atmosphere and reconstructions show that concentrations of CO2 in the atmosphere have varied, ranging from as high as 7,000 parts per million during the Cambrian period about 500 million years ago in ancient-Earth biospheres to as low as 180 parts per million during the Quaternary glaciation of the last two million years.

So this bears out the thesis that even the 400 ppm figure that everyone is so worried about is on the very low end of what Life is used to. As you point out, much lower than the present 300ppm and plants are essentially starving. It's already been shown that as CO2 has increased, various deserts are starting to 'green up' - the plants there were not suffering from lack of water but lack of CO2. If the viable range is, say, 200 ppm to 7000 ppm, then it's arguable to say that a reasonable mean would be either 3400 ppm (arithmetic mean) or about 1180 (geometric mean).

Comment: Re:Going against consensus is scientific ... (Score 1) 573 573

Hendrik Svensmark, one of the original members of IPCC, is just one of several original well-respected scientists who left IPCC in disgust a number of years ago after their results were doctored in the official report, eliminating all mention of any results that contradicted the official message - this is just bad science. IIRC some of the results were left in the largely-unread-by-politicians complete science publication. It's also plain from his own statements that Rajendra Pachauri who ran the IPCC from the beginning until recently not only has a religious belief in Global Warming regardless of any evidence, but is also somewhat of a sociopathic personality, who won't let anyone or anything stand in his way to get what he wants - the most recent scandal had to do with sexual misconduct in India, which finally has caused him to resign from IPCC. Perhaps now IPCC will be allowed to become a true scientific effort.

Comment: Re: GPG is another TrueCrypt? (Score 1) 309 309

Well put. I work for a company that provides a secure "Proof of Knowledge" support for web logins. (Proofs of knowledge include text passwords, picture passwords, Captcha, etc. - things that require personal knowledge or cognitive self-tests.) The security model for this SAAS is highly motivated by user privacy and security concerns. The actual proof - the password, or whatever - is encrypted into a hash in the browser, and stored as a doubly-encrypted hash in the server. The SAAS never knows the user's identity, only an encrypted code that identifies the user to the requesting website. So connecting the user, the website's user ID, and the proof requires hacking or compromise of all three pieces of the puzzle.

It is even possible (though we haven't rolled out this capability to production yet) for the actual challenge to be encoded by the user in such a way that it's impossible for anyone but the user to even know what the test to be performed is. I won't say how this is done, as the patent is pending.

A fail-safe circuit will destroy others. -- Klipstein