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Post by ka9q on Jul 21, 2011 0:32:05 GMT -4
I hate to tell you lot this, but the general idea of "simple language" around here seems to presuppose you not only took and passed calculus I understand, and I'm always looking for better and clearer ways to express technical ideas. Your suggestions are appreciated. |
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Post by gillianren on Jul 21, 2011 1:45:09 GMT -4
The problem is that, for a lot of us, the numbers literally don't mean anything. This is one reason a lot of uneducated people get fooled by HBs. Your numbers could be right or theirs could; we don't know. (Note that I'm hardly uneducated, but my math and science education is at a much lower level than a lot of people here. I've never taken calculus, and while my physics class was fun, that wasn't from learning physics.) Now, the numbers are important. I have a great respect for the numbers--and those who can make sense of them. And if you understand them, they are literally the simplest way to explain what you're talking about. But I don't, Fattydash didn't, and quite a lot of other people don't.
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Post by redneckr0nin on Jul 21, 2011 1:53:16 GMT -4
The problem is that, for a lot of us, the numbers literally don't mean anything. This is one reason a lot of uneducated people get fooled by HBs. Your numbers could be right or theirs could; we don't know. (Note that I'm hardly uneducated, but my math and science education is at a much lower level than a lot of people here. I've never taken calculus, and while my physics class was fun, that wasn't from learning physics.) Now, the numbers are important. I have a great respect for the numbers--and those who can make sense of them. And if you understand them, they are literally the simplest way to explain what you're talking about. But I don't, Fattydash didn't, and quite a lot of other people don't. It is not hard to understand the numbers if you put a little time in. I did that last year when I first started studying this theory. In part I also started to study one of the most fascinating topics to me in life......Black Holes. Now in the beginning I had no clue what the physics were telling me about them( I studied physics in High School but like you I don't have the best grasp of all the math). So I started slow and with the help of a great site WolframAlpha.com I started to slowly learn what it was telling me. Now after that there is not one subject I am afraid to tackle knowing that if I dedicate myself to learning it I can and will eventually figure it out! |
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Post by nomuse on Jul 21, 2011 1:57:50 GMT -4
I'm still largely innumerate but I've been getting slowly better. Learning details about Apollo has helped. I also have a long-term friend who does NOT suffer from that problem. We frequently do napkin sketches over brunch in which he fires off a lot of basic measures; "So, a two-story wooden house weighs n tons, and the powerplant of a diesel locomotive puts out n watts, and the density of thorium is n, so multiply by the speed of sound in dry air and you get..."
It is HARD to get an instinct for just how heavy a car is, how much Ke it carries when moving at freeway speeds, et al. This is part of how H.B.s (and other conspiracy theorists) get so conflicted where their instincts tell them how something will behave, and the actual scale of the numbers involved does something very different. You see this all the time; "The batteries would have been huge!" or "It would have taken too much water!" or "It wasn't moving fast enough!"
And, I think, it goes one step deeper. They aren't used to working in numbers, so to them actually calculating the necessary battery weight for the Rover doesn't feel as "real" as letting instinct tell them how many kg of batteries would be needed. Whereas us recovering innumerate can at least know that the calculation -- if performed correctly -- trumps instinct: even if we lack the experience with the typical range of the numbers to be able to know instinctively the ballpark of the calculation before we even do it.
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Post by redneckr0nin on Jul 21, 2011 2:02:18 GMT -4
I'm still largely innumerate but I've been getting slowly better. Learning details about Apollo has helped. I also have a long-term friend who does NOT suffer from that problem. We frequently do napkin sketches over brunch in which he fires off a lot of basic measures; "So, a two-story wooden house weighs n tons, and the powerplant of a diesel locomotive puts out n watts, and the density of thorium is n, so multiply by the speed of sound in dry air and you get..." It is HARD to get an instinct for just how heavy a car is, how much Ke it carries when moving at freeway speeds, et al. This is part of how H.B.s (and other conspiracy theorists) get so conflicted where their instincts tell them how something will behave, and the actual scale of the numbers involved does something very different. You see this all the time; "The batteries would have been huge!" or "It would have taken too much water!" or "It wasn't moving fast enough!" And, I think, it goes one step deeper. They aren't used to working in numbers, so to them actually calculating the necessary battery weight for the Rover doesn't feel as "real" as letting instinct tell them how many kg of batteries would be needed. Whereas us recovering innumerate can at least know that the calculation -- if performed correctly -- trumps instinct: even if we lack the experience with the typical range of the numbers to be able to know instinctively the ballpark of the calculation before we even do it. Exactly and also being the ones that didn't understand the numbers once I feel we can translate that to the few HB that are unsure but will honestly put in a effort to see for themselves if we landed on the moon! |
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Post by nomuse on Jul 21, 2011 2:12:01 GMT -4
There are some HBs who do numbers.
What I'm not sure of is if they are more to the side of treating numbers with the same essential dishonesty of everything else they do; using them as a club to convince others, and making up numbers as they please, instead of using them as a tool to learn something. Or if they are more to the side of trying honestly to do numbers but being so misled by their previous beliefs they rationalize sticking in the wrong ones or not bothering to look up the right ones, leaving out important factors or putting in fudge factors, in order to get results they like.
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Post by redneckr0nin on Jul 21, 2011 2:17:34 GMT -4
There are some HBs who do numbers. What I'm not sure of is if they are more to the side of treating numbers with the same essential dishonesty of everything else they do; using them as a club to convince others, and making up numbers as they please, instead of using them as a tool to learn something. Or if they are more to the side of trying honestly to do numbers but being so misled by their previous beliefs they rationalize sticking in the wrong ones or not bothering to look up the right ones, leaving out important factors or putting in fudge factors, in order to get results they like. I agree with that totally. With numbers....or any other part of the debate used as proof I argue both sides to myself and see what part makes more sense. You are right in the fact that every HB seems to omit something from the big picture. The best example was one tried to tell me that if I watched Apollo:Dark side of the Moon I would discover that Henry Kissinger and Donald Rumsfeld are in it admitting to the government faking the whole thing. Now he was right but in typical HB fashion he never zoomed out and looked at the big picture. That movie is FICTIONAL and everything in there taken out of context...I find that to be the case with all HB. I try not to get into arguments with them as much just noticing when there is someone that genuinely wants to know if we achieved this feat or not is when I get involved for the most part! |
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Post by gillianren on Jul 21, 2011 2:41:38 GMT -4
I've tried learning the numbers. They won't stick in my brain. Putting "a little time in" doesn't do it for me. My eyes just slide right over them.
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Post by nomuse on Jul 21, 2011 6:03:18 GMT -4
For me the main part of the trick was -- err, is -- working with the numbers a lot. Over years. Decades. I still get pretty far off in a lot of magnitude stuff though. And that's what I mean about the sense of the number; not knowing the joules in a battery down to the decimal point, but knowing whether it makes more sense to describe the storage of a AA battery in joules or kilojoules.
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Bob B.
Bob the Excel Guru?
Posts: 3,072
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Post by Bob B. on Jul 21, 2011 9:24:11 GMT -4
The problem is that, for a lot of us, the numbers literally don't mean anything. This is one reason a lot of uneducated people get fooled by HBs. Your numbers could be right or theirs could; we don't know. (Note that I'm hardly uneducated, but my math and science education is at a much lower level than a lot of people here. I've never taken calculus, and while my physics class was fun, that wasn't from learning physics.) Now, the numbers are important. I have a great respect for the numbers--and those who can make sense of them. And if you understand them, they are literally the simplest way to explain what you're talking about. But I don't, Fattydash didn't, and quite a lot of other people don't. I can appreciate your problem. And I acknowledge that I’m probably the guiltiest among us at throwing numbers around. The problem is that many of the claims made by HBs require a quantitative argument that they are ill-equipped to make. Most recently, pleasedebunkme’s claim about the structural strength of the CM. He threw something out there that simply couldn’t be discussed until he put some numbers to it. Jay immediately challenged him to provide a quantitative and quantified argument. When he couldn’t do it, the whole thing was pretty much dropped, though he never officially retracted the claim. On the flip-side, if we make a claim and not put forward a quantitative and quantified argument when required, then we’re doing the same thing as the HBs. Sometimes the numbers just have to be put out there to make the argument complete. I realize that many people, probably most, are not going to understand the numbers. Even if only 10% of the people have the adequate math skills, then that’s 10% of the people who now understand. That’s a good thing. To the other 90% we have to try to explain without math, but that’s not a reason to not put the mathematical argument out there for the mathematically inclined minority. I do the math just to get it on the record and say here it is, if you want to challenge the numbers I here and I’m willing to discuss it. If the HBs don’t challenge the numbers, then either they agree with them or, more likely, they don’t understand them. In either case, they are exposed as charlatans. Often I try to provide some narrative to go along with the math, which I hope reaches few more people who may not understand the math per se. And I’m always willing to discuss the meaning or consequences of the quantitative argument in plain words if I'm asked questions. I rarely get questions, however. Gillianren, even if you don't understand the math, don't be afraid to ask "what does that all mean." We may be able to boil it down into a simpler non-mathematical argument. |
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Post by grmcdorman on Jul 21, 2011 9:51:05 GMT -4
I think fattydash had an even more basic problem: he couldn't - or wouldn't - understand the difference between precision and accuracy. That was one of the issues with the landing coordinates.
OT: I have a wireless temperature sensor. The display, in Celsius, has a precision of 0.1 degree. The manual says it has an accuracy of +/- 1 degree. What is the point of the extra digit on the display? ;-)
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Post by gillianren on Jul 21, 2011 12:29:47 GMT -4
Often I try to provide some narrative to go along with the math, which I hope reaches few more people who may not understand the math per se. And I’m always willing to discuss the meaning or consequences of the quantitative argument in plain words if I'm asked questions. I rarely get questions, however. I think quite a lot of the time, the response to the numbers is not a question about what they mean because there can be a feeling around here that any idiot should know what they mean. As I said, I know exactly how important the numbers are, and I know that numbers are the language of science. (Hey, I watched "Donald in Mathmagic Land" the other day!) However, the people who come here because they genuinely have questions have often been sent here by someone else's numbers which they're trusting because they don't understand numbers. I think it's important to be sure the narrative is always there, to make sure that the numbers attach to something. This is in part because I believe that, the more cohesive a unit you make of Apollo, the more obvious it is that there's no "lynchpin." I know that because I study history. Most of you know it because you've studied science and engineering. But I don't think a lot of people have ever learned that. It doesn't come into their world. They've been persuaded by people who told them that any little error can mean the whole thing is bogus, and by showing where the numbers relate, we can help dispel that notion, which is a dangerous one to have. |
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Post by JayUtah on Jul 21, 2011 13:28:00 GMT -4
I think fattydash had an even more basic problem: he couldn't - or wouldn't - understand the difference between precision and accuracy.I agree, and the difference is vital to anyone who works with measurement for a living, be he a doctor or an engineer. Accuracy means how closely the measurement matches the actual value. If your thermometer is said to be accurate to +/- 1 degree C (roughly 2 degrees F), that means the number on the dial will be within a degree either side of the actual temperature as measured by some theoretical, magical thermometer that's never wrong. Put in non-measurement terms, a rifle is accurate if you place the crosshairs on the bullseye and the bullet hits the bullseye. If it lands somewhere else on the target, your rifle is less accurate. My car's analog speedometer reads 80 mph when the actual ground speed is 75 mph, as measured by timing over a measured mile and by GPS. This would be poor accuracy if you needed to know your ground speed down to a single mile per hour. Precision is a statistical understanding of how closely repeated measurements give the same answer for the same subject quantity. That is, does the speedometer needle wiggle as you drive a constant speed? In the rifle example, it's the size of the shot group assuming the rifle was locked into a vise and couldn't move. If all the bullet holes fall within a very small circle, the rifle is precise. Now that shot pattern may be some distance from the bullseye, and that would be a rifle that is precise but not accurate. In contrast, a rifle that is accurate but not precise would have a wide shot pattern nevertheless centered on the bullseye. Similarly if my speedometer needle wiggles around 75 mph when I am actually driving 75 mph, it too would be accurate but not precise. An imprecise thermometer's dial reading would change rapidly over time, even if there's no change in the temperature. Instruments that are accurate but not precise can yield useful measurements if their results are statistically treated -- i.e., filtered, say by a rolling average. Instruments that are precise but not accurate can yield useful measurements if a calibration function is known. To bring this home, the IMU in an Apollo spacecraft is precise to around a thousandth of a degree of arc. That is, if the spacecraft doesn't move, repeated sampling of the IMU gimbal angle measurements will not change by more than 0.001 degree. However, the accuracy of the IMU is determined by how far its orientation drifts off true over some period of time. It may be giving you repeatedly stable measurements of 36.776 degree, but that may be well off the actual angle of 39 degrees. IMU alignment corrects accuracy. Proper engineering and operating methods provide precision. Inaccuracy often derives from the lack of fidelity in the underlying measurement model. That's a fancy way of saying that what you're really measuring is rarely the quantity that you're directly interested in. Measuring temperature is typically really to measure the height of a mercury column, or the degree of deflection in a bimetallic strip, or the change in electrical properties in a semiconductive material. All these methods rely on measurable physical effects that are proportional to temperature and causally related to it, but are not absolutely covariant. ("Covariant" means "changes at the same time for the same reason.") Mercury columns are affected also by bulk modulus and capillary effects. Bimetallic strips are affected by elasticity, age, and chemical contamination. Semiconductors are subject to electromagnetic interference and molecular breakdown. Being able to convert the measured quantity into a usable estimation of the desired quantity is an art and science to itself. Old scientific instruments employed calibration charts to help the operator convert the indicated value to the actual value. One looks up the indicated value on a graph and reads the corresponding real value. These are derived by measuring known reference quantities and plotting between them by curve-fitting techniques (typically a pen and a French curve). Modern calibration can be done electronically or computationally in digital logic. The calibration for my speedometer is in my head. I know there is an approximately linear relationship between the indicated ground speed and the true ground speed such that for an indication of 80 I can take an actuality of 75. By "linear" I mean that it's a simple multiplication factor in all cases. What is the point of the extra digit on the display? ;-)The sensor may actually achieve a precision of 0.1 C, and the display would be appropriate in that case. The inaccuracy can be compensated for by making your own calibration curve. From their data sheet you know that the true temperature is not likely to vary by more than 1 C from the indicated temperature. By taking a series of samples over the useful range of the instrument an applying an appropriate curve fit, you can calibrate the display. If your sensor is precise, and well-calibrated, you can know the true temperature to comparable precision as the indicated temperature. So if it always indicates 28.4 C (to that precision) for a precise true temperature of 28.9, then you can rely upon the indication.
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Bob B.
Bob the Excel Guru?
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Post by Bob B. on Jul 21, 2011 14:07:53 GMT -4
I think it's important to be sure the narrative is always there, to make sure that the numbers attach to something. I usually make an effort to do that but I don't always succeed. I'll try to do better, at least when posting in the forum. I don't know if you've ever read my moon hoax page, but there I tried to avoid math as much as possible because I knew most people reading won't understand it. On the other hand, the simulations are analyzes that I did here are extensively mathematical, but they have to be because it's rocket science. I realize the percentage of people who can follow what I did is small, but the point is to put it all out there on the table and show every source, every assumption, and every calculation. I'm exposing everything so it can be challenged and debated. I'm not trying to blow smoke or dazzle and befuddle people with numbers. I'm trying to show the correct way to deal with these issues, which are mathematical by nature. HB handwaving doesn't cut it. |
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Post by ka9q on Jul 21, 2011 14:31:09 GMT -4
My car's analog speedometer reads 80 mph when the actual ground speed is 75 mph, as measured by timing over a measured mile and by GPS. Are your tires underinflated? |
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