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Comments

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The Documents From Google's First DMV Test In Nevada

JimFive Re:Who would have thought (193 comments)

The thing that bugs me the most is when the driver in front of me stops at the yield before the roundabout because someone is approaching (not in) the roundabout from the left or just got in the roundabout from the right. The whole point is that you can get on the roundabout AND the person to the left can get on the roundabout at the same time. It's not a one car at a time thing.
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JimFive

5 days ago
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Link Between Salt and High Blood Pressure 'Overstated'

JimFive Re:Obviously. (291 comments)

Isn't the entire point of this article, and nutrition research in general, that we don't have a clue what constitutes "a well balanced diet". It's all very cute and snarky to say "eat right and exercise" but when the topic is "What does it mean to eat right?" it isn't a very useful response.
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JimFive

5 days ago
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Information Theory Places New Limits On Origin of Life

JimFive Re:Gibbs Free Energy (211 comments)

The point that confuses me is: the energy on the outside lens surface can't light a fire, but the energy produced by the glass can. What work was done on the outside energy? It was redirected inside the lens, but how is that work? Doesn't work in thermodynamics reduce to the lifting of a mass in a gravitational field? How is the lens doing any work, in that sense?

There is (approximately) the same amount of energy on both sides of the lens (presumably a small loss into the lens itself). If you measure that energy directly off of the lens on both sides there won't be much difference (you can touch both sides of the lens without getting burnt), but because the direction of the energy has changed, the density of the energy at the focal point is higher than at the lens. So, there is more energy per square mm at the focal point, and presumably less energy per square mm in the area around the focused light than in the ambient area unaffected by the lens shadow (I wonder if that is measurable).
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JimFive

5 days ago
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Surprising Result of NYC Bike Lanes: Faster Traffic for Cars

JimFive Re:Bikes lanes are nice (213 comments)

Walkers can stop instantly, Cyclists take a bit longer. In addition, there is a much longer time window for the car and pedestrian to see and avoid each other at a driveway than there is for a car and a cyclist.

Cyclists are, generally, safer on the road than on sidewalks. Drivers see and stop for road traffic, not for sidewalks. By being in the road, a cyclist is where the drivers are looking. In addition, sidewalks have many more crossing intersections than roads do. Every driveway crosses the sidewalk, but none of them cross the road.

It should also be noted that in many places bicycles are forbidden from being ridden on the sidewalks.

The truly important thing is for everyone to follow the rules. Cyclists on the road must stop at stop signs, not pass on the shoulder, signal turns and stops, etc. And the cars around them should treat them respectfully, move over to pass, don't pass and turn, don't honk, etc. Cyclists on the sidewalk are pedestrians and should act as such, ride more slowly, cross in crosswalks, wait for cross signals and traffic, etc. Additionally, cyclists transition from sidewalk to road (pedestrian to vehicle) should do so safely and should not do so for convenience (don't pop up on the sidewalk to avoid traffic and then pop back onto the road).

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JimFive

about a week ago
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Low-Carb Diet Trumps Low-Fat Diet In Major New Study

JimFive Re:Please stop spreading such drivel (588 comments)

The healthiest diet is what your body needs, and what your body needs depends on your individual body chemistry, your environment, your lifestyle, and probably a half a dozen other factors.

You seem to be implying that we can never know anything about diet because each specific case differs from the general case. That seems to be a fairly pessimistic attitude regarding the ability of experimental science to tease out commonalities and processes in human biology.
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JimFive

about two weeks ago
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Low-Carb Diet Trumps Low-Fat Diet In Major New Study

JimFive Re:Personal mistakes vs. governmental ones (588 comments)

it also leaves millions directly controlled by the government — such as pupils in government schools [nytimes.com] — without choices at all.
...
and parents, rather than the Federal government, be allowed to control the children's nutrition

You realize that the existence of school lunch standards does not preclude the parent from packing a lunch for their children, right? The school lunch program is not shoving food down the kids' throats. If you want your kid to have whole fat, white milk, then pack it for them.

I do agree that the standards are wrong in places, maybe in lots of places, but the existence of those standards doesn't take away parental choice and responsibility.
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JimFive

about two weeks ago
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U.S. Senator: All Cops Should Wear Cameras

JimFive Re:so adjust the rules (643 comments)

That should give officers incentive to ensure their cameras are in working order.

And encourage miscreants to find ways to remotely disable the camera.

I actually agree with your statement, missing camera footage should be treated as destroyed evidence (which, as I understand it, is treated as if it would support the other side). But there is potential for abuse on the other side, also.
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JimFive

about three weeks ago
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Writer: Internet Comments Belong On Personal Blogs, Not News Sites

JimFive Re:Also, this is silly: (299 comments)

And as in real life, the only way to deal with those people is to physically remove them from the conversation. That is, have a moderator whose job it is to delete the posts and evict the poster, even if it is a throwaway account.

Threading helps, too. It is a huge pain to try to follow a conversation on an unthreaded comment system.
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JimFive

about a month ago
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Writer: Internet Comments Belong On Personal Blogs, Not News Sites

JimFive Re:Fix netnews instead (299 comments)

I would actually like it if all commenting interfaces gave up, and we fixed netnews,

I agree with this, I would very much like to be able to use a preferred, threaded client with offline capabilities.
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Jimfive

about a month ago
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Writer: Internet Comments Belong On Personal Blogs, Not News Sites

JimFive Re:Don't allow jpg or gif or ... (299 comments)

Post to remove accidental moderation. --- Sorry

about a month ago
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Passport Database Outage Leaves Thousands Stranded

JimFive Re:Change management fail (162 comments)

How about, instead of asking "Do you have an action plan?" ask, "What is your action plan?" or "Please send me your action plan."

about a month and a half ago
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'Just Let Me Code!'

JimFive Re:"Just let me build a bridge!" (372 comments)

We need thinkers who can define requirements precisely, designers who can describe processes to produce those results, and then turn the design (UML. Warnier-Orr, Flowchart, etc.) over to a generator

We already do this, that generator is called a compiler. By the time you have specified a design to the same detail as an engineer specifies a bridge you have already written all the code. Engineers specify a design down to every individual bolt. Software specifications do not design down the individual line of code. This is the difference between engineering and programming: in engineering when a design is completed then the object still has to be built, in programming when the design is completed then the program is done.
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JimFive

about 2 months ago
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How One School District Handled Rolling Out 20,000 iPads

JimFive Re:We shall see. (285 comments)

We definitely had that multiplication table nonsense when I was in school. The result was that most people forgot most of them and ended up having to calculate them manually.

Seriously? You think that MOST people in your class forgot single-digit multiplications (even as they continued to use them daily) and started counting on their fingers (or drawing dots on paper)? Because that's what "calculate them manually" means, doing it by hand. There are 3 ways to do single digit multiplication: memorize, count, or restate the problem into problems that you have already memorized. Restating requires that you have a sufficient number of the problems memorized for it to work.

They are. I saw it in action myself. The 'teaching' methods you describe don't go into the full picture at all.

The teaching methods I describe are first grade and addition/multiplication using tokens is a perfect example of what those operations actually are and quite helpful in moving from physical manipulation to the symbolic manipulation of arithmetic. If you think that there is more to either of those operations than can be shown by an array of stones on a table then please, enlighten me. That grid of tokens can show commutation, distribution, association, primality, squareness, divisibility, etc. Moving that physical representation to a symbolic system is what arithmetic in lower elementary is about. I submit that knowing the answer to those 45 problems without having to spend time figuring them out every time is useful to the student and everyone who has ever complained about cashiers being unable to make change agrees with me.
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JimFive

about 2 months ago
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How One School District Handled Rolling Out 20,000 iPads

JimFive Re:We shall see. (285 comments)

So, when you do the problem 7*8 what is your thought process?

You seem to be hung up on the idea of a literal table of math problems, while I think I've been pretty clear that I'm referring to a figurative table that is the collection of 45 single digit problems that make up the basics of symbolic arithmetic manipulation. And, I think it is safe to say that you have a significant number of them memorized.

about 2 months ago
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How One School District Handled Rolling Out 20,000 iPads

JimFive Re:We shall see. (285 comments)

If you know 9x6

I actually don't. I had to think about it for a split second.

Sure and what did you think? You certainly didn't think 9+9 is 18 and 18+9 is 27 and 27+9 is 36 and 36+9 is 45 and 45+9 is 54, which is what you get from "an understanding of multiplication" without having any memorized answers. You seem to believe that you haven't memorized these things but if you are not counting on your fingers to add numbers together then you HAVE memorized these things, and you probably memorized them so long ago that you can't remember not knowing them. Certainly, there are tricks that make mental math easier, but those tricks still rely on you having memorized a sufficient set of single digit addition and multiplication problems.

I don't buy your logic that because someone has to think about it for a second, then they suddenly won't know what's going on.

It's not a second. If it's a second then they have enough stuff memorized to do the arithmetic. It seems that you've never worked with a student struggling with basic arithmetic such that it takes them 15-30 seconds to do 15+27, if they do it all without giving up. By that time the teacher is on a different problem and the student is falling further behind.

Using a tool often does not mean you don't understand how and why multiplication works.

Using a calculator before you understand how and why multiplication works means that you are likely to never understand. You seem to be under the impression that memorizing of tables is used in place of teaching how the operations work. Children are taught to add using tokens on a desk, dots on a line, and marks on a page, then they are pushed to memorize the single digit answers. Multiplication, similarly, starts with making rectangles of tokens and then moves onto paper before memorization of the answers.

The basic material is important. Memorizing a table or results, however, not so much

In arithmetic the only thing more basic than single digit addition is the numbers themselves.

The problem with rote learning is not in the memorization of simple arithmetic facts. The problem with rote learning in mathematics comes when you start doing mathematics instead of arithmetic.
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JimFive

about 2 months ago
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How One School District Handled Rolling Out 20,000 iPads

JimFive Re:We shall see. (285 comments)

Did you know that current tests are absolute garbage and are part of the reason the education system itself is abysmal?

You're talking about standardized tests, I'm referring to in classroom tests.

I never truly memorized the table and yet I understand math

You are being disingenuous. If you know 9x6 without thinking about the answer then you have memorized it, whether you ever filled out a grid with the answers is irrelevant to whether you have memorized the material.

It's absolutely ridiculous to say that someone cannot follow along in a fucking algebra class if they don't memorize the results of calculations

If the teacher is demonstrating a problem, e.g. 6x-27 = 15 and for the next step writes 6x=42 it is surely easier for the student to follow along if they can quickly see that 27+15 = 42 without having to write it out and calculate it.

tool-using creatures

You can't gain understanding if you fall back on a calculator for basic knowledge. Now, whether you think it is valuable to be able to do long division it is practically impossible if you don't know single digit multiplication. A student who knows the multiplication table will be able to complete a quiz on division while the student who doesn't, won't. I'm not saying that students should never use calculators, I'm saying that learning the basic material is important and until you've learned it a calculator is a hindrance.

As an aside, they don't seem to actually teach it as a table any longer, which is good because learning them as separate facts prevents relying on the patterns of the table format.
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JimFive

about 2 months ago
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How One School District Handled Rolling Out 20,000 iPads

JimFive Re:We shall see. (285 comments)

Math is not about speed to begin with.

It is when you have maybe 45 minutes a day to teach it and you have to give timed tests. Memorization of the addition and multiplication tables is not done just for its own sake; it is done to facilitate later learning. It is done so that in classes such as algebra the teachers can skip a couple of details and still expect the students to follow along. It's done because dealing with big numbers is easier if you already know the answers for small numbers without having to calculate it out every time.
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JimFive

about 2 months ago
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How One School District Handled Rolling Out 20,000 iPads

JimFive Re:Yeah, students will use bandwidth (285 comments)

Funding overall may be going up, but at least around here, general funding isn't very good. iPods, etc are bought with grant funds while teachers are paying out of pocket for basic classroom supplies.
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JimFive

about 2 months ago
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How One School District Handled Rolling Out 20,000 iPads

JimFive Re:Yeah, students will use bandwidth (285 comments)

That is not happening in a household where the single parent works 3 jobs.

The way to fix that is after school clubs and activities.

No, the way to fix that is to structure our society so that a person only needs to work 1 job to support their family. Potential ideas might include subsidized daycare, wage supports, basic income, increased availability of and respect for adult education, better transit systems, etc.
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JimFive

about 2 months ago

Submissions

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Flying Cars

JimFive JimFive writes  |  more than 4 years ago

JimFive (1064958) writes "For years we've been waiting for the flying car to arrive. The FAA has made an exemption that moves this one step closer to reality. Terrafugia has been granted a weight limit exemption for a "Roadable Airplane". Next up is passing the federal highway safety tests. The press release is here.."
Link to Original Source

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