Distance metric learning is a branch of machine learning that aims to construct task-specific distance metrics from weakly supervised data in a machine learning manner. This learned distance metric can be used for various tasks, such as k-NN classification, clustering, and information retrieval. Distance metric learning enhances the performance of similarity-based algorithms, such as nearest neighbors classifiers.
This tutorial covers the mathematical foundations, algorithms, experimental analysis, prospects, and challenges of distance metric learning. Metric-learn package with scikit-learn is used to compute pairwise distances between samples using various metrics, such as Euclidean, Manhattan, Hamming, and more. Distance metrics play an important role in machine learning, providing a strong foundation for several machine learning algorithms like k-nearest neighbors for supervised learning.
In this ninth segment, we will explore deep distance metric learning, its motivation behind using it, wide range of methods proposed, and its applications. Many algorithms rely critically on being given a good metric over their inputs, such as data being clustered in many “plausible” ways.
MLKR is an algorithm for supervised metric learning that learns a distance function by directly minimizing the leave-one-out regression error. The technique discussed in this article comes under Deep Metric Learning (DML), which uses neural networks to construct distance metrics from weakly supervised data.
In summary, distance metric learning is a crucial aspect of machine learning that enhances the performance of similarity-based algorithms. By understanding the mathematical foundations, algorithms, experimental analysis, prospects, and challenges of this branch, users can improve their machine learning models for classification tasks and clustering.
📹 Rule of Thumb – Distance(EASY !!! ). NoMath Needed
Hallo, after watching some Videos about Messuring Distance with your Thumb, and they were all very out of Space Mathematic …
How to calculate distance metrics?
The Manhattan distance and Euclidean distance are two metrics used in machine learning models. The Manhattan distance is faster to calculate due to its smaller values, while the Euclidean distance takes the square root of the sum of squared vector values. The choice between these metrics depends on accuracy and speed tradeoffs. Manhattan distance is faster as the data dimension increases, but it is not necessary to square differences. It is best to use the distance metric that matches the model used, such as the contrastive loss function in a Siamese Neural Network (SNN) or the loss function in a sentence transformer.
The CosineSimilarityLoss is a common choice for calculating similarity based on cosine similarity between two embeddings. For more information on distance metric usage in high-dimensional spaces, refer to Aggarwal et al.’s paper.
What is the rule of thumb for distance?
The distance between your eyes and your thumb is about 10 times the distance between your eyes, making the distance of a faraway object about 10 times the width your thumb seems to move from that object. Parallax exists because humans have two eyes positioned apart, allowing the eye to gain depth perception and estimate distances. Some animals use motion parallax, moving their heads to gain different viewpoints, such as birds with monocular vision, pigeons using motion parallax, and owls with binocular vision.
This simple eye-to-finger rule is useful for estimating the distance to distant landmarks, such as trees, water towers, or trailhead parking lots. With practice, you can perform a quick thumb estimate in seconds and test the accuracy of this estimate.
What is the distance learning metric?
Distance metric learning is a method that aims to identify the optimal metric for comparing instances of the same person with those of different individuals. The method entails the utilisation of cookies for the purpose of monitoring user behaviour, with the objective of ensuring that instances are correctly classified as either similar or different. This approach is particularly useful in the context of text and data mining, AI training, and similar technologies.
How do I choose a metric?
To select the right metrics for your organization, it’s essential to understand their purpose and impact on your business goals, customer needs, and decision-making process. Focus on metrics that drive customer choice and satisfaction to ensure your measurement efforts are fit for purpose. Once you’ve identified the right metrics, make them actionable by defining clear thresholds for success and failure, and regularly analyzing and interpreting them to gain valuable insights and guide decision-making.
Metrics should inform your business strategy, help identify improvement opportunities, and drive growth. By understanding different categories of metrics and their relevance, you can avoid collecting non-actionable or misleading data. Focus on customer fitness criteria, monitor health indicators, utilize improvement drivers, and be cautious with vanity metrics. Choosing the right metrics will empower your organization to thrive in today’s competitive landscape.
What is the easiest way to measure distance?
The ruler is the simplest type of length measurement tool, defined by printed marks or engravings on a stick. The metre was initially defined using a ruler before more accurate methods became available. Gauge blocks are a common method for precise measurement or calibration of measurement tools. For small or microscopic objects, microphotography can be used with a graticule, which has lines for precise lengths etched into it.
A transit-time measurement of length involves sending a signal from one end of the length to the other and back again. The time for the round trip is the transit time Δt, and the length ℓ is then 2ℓ = Δt*”v”, with v the speed of propagation of the signal. If light is used, the speed depends on the medium in which it propagates, with a defined value c0 in the reference medium of classical vacuum.
Length measurements are not subject to knowledge of the source frequency, but are subject to errors in measuring transit times, particularly due to response times of pulse emission and detection instrumentation. Additionally, a refractive index correction relating the medium used to the reference vacuum is also an uncertainty.
How do you calculate distance quickly?
The calculation of distance is based on the principle of dividing speed by time.
How do you learn distance formula?
The distance between two points is calculated by first squaring the difference between the two coordinates, then subtracting the y-coordinates, adding them together, and finally taking the square root.
How do you choose metric distance?
The choice of a distance metric in machine learning significantly impacts the performance and accuracy of predictions. It is crucial to consider the data’s nature, the problem statement, and the algorithm used when selecting a distance metric. Distance is the space between two things, and it is used in machine learning to understand how similar or different things are from each other. Different ways to measure distance affect how things are grouped, and there are different distance metrics used in machine learning.
The right distance metric for a problem can significantly impact the results obtained. To learn more about distance metric selection, subscribe to the YouTube channel and follow the author on Instagram.
What is a learnable distance metric?
Distance metric learning is a machine learning technique that automatically constructs task-specific distance metrics from weakly supervised data. These metrics can be used for tasks like k-NN classification, clustering, and information retrieval. Traditionally, standard distance metric measures are chosen based on domain knowledge, but designing metrics that are well-suited to the specific data and task can be challenging.
Metric learning problems can be categorized into two main types based on the type of supervision available about the training data. This approach can help improve machine learning techniques and improve the accuracy of data classification and retrieval.
How to do metric conversions easily?
The metric system is a widely used method of measuring distance, height, and other everyday items. It is based on the International System of Units (SI) and is used in various fields such as science, medicine, governance, and defense. Common conversion formulas include multiplying m to cm by 100, cm to mm by 10, km to m by 1000, kg to grams by 1000, and grams to mg by 1000.
The metric system is based on the decimal system, which includes numbers in powers of 10. It is used in various fields such as science, medicine, governance, and defense, and is used to convert various units such as liters to meters, meters to meters, and grams to meters. The conversion formulas for m to cm, cm to mm, km to m, kg to grams, and grams to mg are all part of the metric system.
What is the distance learning formula?
The distance formula, d = (x 2 – x 1 ) 2 + (y 2 – y 1 ) 2, is a mathematical concept that is typically introduced in the eighth grade and then revisited in high school geometry as a means of expressing geometric properties with equations. The distance formula assists students in determining the distance between two coordinates and is consistent with standards-aligned one-on-one tutoring in mathematics for educational institutions and their respective districts.
📹 Distance Metric Learning On The L1000 Connectivity Map
Ian Smith, Ph.D., with the University Health Network, gave a short talk at the BioConductor Conference 2022. Smith gave his …
I use a different technique but instead of distance I measure time until dark, something I’m learned as a pilot to calculate how much daylight remained. Simply extend an arm before you and set the edge index finger on horizon. Add fingers till you touch the bottom of the sun. Each finger equal 15 min. Eg, index finger and 3rd fingers between horizon and sun is 30 mins. Works very accurately. Granted if sun is obscured it does present challenges. Otherwise it’s a very quick calculation.
Years ago I noticed my Thumbnail was the same height as an “E Type” target at 300m, later on at an important test course I judged the distance of the target at 600m, I was taken back and grilled, almost expelled from the course before I explained my “Thumb/target” method, After a visiting SGM was called to supervise the situation I was given a “Pass” on that part and asked to explain the method again to the others (The target was exactly 600m). Good article.
Thanks for that. The reason it works is because the distance to the thumb from your eye of the outstretched arm is approximately 10 times the distance between your pupils. This means that both measurements will have a ratio of one to ten, the distance being 10 times that of the width. The distance of the object is from the thumb, so for very close objects you would need to consider that.
This is a great tip. Keep in mind that different people may see more or less of a shift when alternating their view with each eye. The effect this has, is their multiplier may be different than yours (you used “multiply by 10” in the article), but it should still be proportional so it should still work. For example, when I do this, the “shift” I see is perhaps considerably more, so the multiplier, for me, should be less, perhaps 7 or 8 rather than 10. A person can figure out their “personal multiplier” either by: 1) Trial and error repeating the process trying different multipliers until you find the most accurate multiplier, or 2) By pacing off say 100m from an object (tree) and setting a pole or tall stake marking your second “thumb-view” (a second person can help with this), then measure the separation of the tree to the pole (say it was 9m), and calculate the multiplier as the “tree-distance” divided by the “offset-distance”, in this example, it would be 100 / 9, so the multiplier would be about “11”. If the “offset-distance” measured 14m, it would be 100 / 14 and the multiplier would be about “7”.
Very interesting. I never thought of using one eye, and then the other, but this is calculating based on trigonometry. You make a triangle from the tree to one eye, and then the other. You estimate the difference between the tree (as seen by the first eye) and the position in line with your thumb with the second eye. I didn’t know about multiplying it by ten to estimate the distance. The pace count is taught by the US Army to follow a map. You pace off 100 meters so that you know how many paces to walk a certain distance. Thanks for an interesting and informative article.
I was taught a similar technique as a sawyer, but it was for finding where a tree would land when you fell it. You take a stick the length of your arm and hold it out at arms length, then get it so the top of your hand is at the spot you’re going to do your cut and walk from the tree to where the tree and the stick look like the same height and thats where the top of your tree will fall.
Additional tip: You can use an height to guess a width in a distance. Target a person (5-6 ft) or an house (10 ft per floor) with a stick. Visualize the height of your target from the top of the stick to your finger. Take your landmarks with each eye. Then turn the stick horizontally and measure how many “heights” you have between the two landmarks. The distance is the height x number of heights x 10. For example I target an house of two stores with no roof (20 ft). Closing each eye, I have two landmarks. Using the stick, I measure they are apart by 3 heights of the house. So the distance from me is 20 ft. x3 x10 = 200 yards. Of course the greater the distance the bigger the inaccuracy.
What’s great about this tip is that it works with any unit. You could use it to approximate miles, meters, or even feet of difference, because the ratios will always be the same. It only relies on a strong ability to estimate the distance between the two positions of your thumb in whatever unit you prefer.
Hallo, and thank you for your post. I have dyslexia. It is a severe learning disorder of reading and memory. I took algebra 5 times (Spanish 5 times, and other racademic courses, in Jounior and Senior HIgh School, and finally was told to leave at age 19 because I was too old to stay in school) but never could get past it. The U.S. Air Force understands how difficult math is for some people, and has developed their teaching of complicated subjects by simple methods. Distance-measuring would be one of them, but it’s not. I look forward to seeing more. At about age 40 I earned a seat in the course on Flight Engineering of fixed wing jets, past it, and became a qualified aircrew member of military cargo jets. No math, just techniques. After military service, I went on to earn an M. A. in English and J.D. (Law). I had to learn how to teach myself, everything. Most dyslexics become class clowns, and juvinile delinquents, or become billionairs, and peopel who design space ships (Elon MusK). Most billionairess in America are dyslexic, as are Hollywood entertainers and prison inmates. You get two thums up! Sgt. Brill, UAF (Ret), THAILAND
Interesting. One important factor is not mentioned, and that’s the distance you must hold the stick away from your eyes. The simplicity of this method depends on the ratio of the distance between your eyes (about 60 mm for adults) and the distance from your eyes (or the bridge of your nose) to the stick (about 60 cm for adults). There is an isosceles triangle with a base of 60 mm (distance between eyes) and an altitude of 60 cm, which is the source of the 10:1 ratio. If you remember from geometry that 1) vertical angles are congruent and 2) similar triangles have the same relative proportions, you can then understand that there is a second isosceles triangle with the base being the apparent distance the object moves, and the altitude is the distance from the stick to the object. I suppose you could “calibrate” yourself by marking off a known distance and finding out your true multiplier ratio, which for most people is around 10.
This works really well over short distances where you can accurately estimate the distance on the ground between both sightings. Estimating that distance eg between two trees with no reference is more difficult. The presence at that distance of a known measurement eg a person or a cow etc greatly helps.
I have determined that my thumb, held at arms’ length, covers up one foot at 10 yards. I can use that to estimate the distance to a recognized object. If I see a person in the distance (assumed 5 or 6 feet tall) and my thumb just covers the person up, the distance is 50 to 60 yards. If the person is twice as high as my thumb, the distance is half that. If the person is half the height of my thumb, it is double that. etc…
It is a simple trygonometry. Your arm length is about 10 times longer the the distance between your left and right eye (usually 50 cm long arm and 5 centimeters from lef to right eye). So you have one tringle on your side of thumb. And there is a second tringle on oposite side of thumb with the same proportions 10:1. Therefore if your thumb moves semingly 20 meters on the landscape this means that the object is 20meters x 10 from you = 200 meters.
Hey works pretty good! Tried it in my living room, there’s a wheel chair on the other side of the room so I held my thumb up and sure enough eye to eye it looked like one foot between so I multiplied by 10 and guess what the chair IS ten feet away! Thanks dude that a good trick to have in your bag!🤠👍🙋♂️
This is based on similar triangles; the triangle consisting of the two eyes and the thumb and the triangle consisting of the thumb and the projected points of the thumb on the distant location. The distance between the eyes is about 2 1/2″. The distance from the eye to the extended thumb is about 2 1/2 feet, so the ration is closer to 12:1. The entire thing depends on the estimated distance between the two projected points at distance. Without something to establish scale, this is more or less a wild guess.
You can also check the height of something using ur right thumb and pinky finger. Hold your right arm straight out about eye level, then extend your thumb and pinky out up and down both ways. Turn your wrist inward toward you, then walk forward or back and put the tip of your thumb at the top of the object and tip of pinky at bottom. Then once inline- pace out steps towards the object. However many paces you take should be close to height of object in feet.
Hi Albert. Let me return the favour 🙂 And this is crucial….. when making tea NEVER bring to boil with the bag in the pot – I shudder. Boil water throw bag in and immediately take pot from heat. let sit maybe 30 – 60 sec. Do NOT squash the bag – yuk. Happy trails matey. ps. now that looks like a comfy bench. wish it was international standard. seeya.
Two things: First, not everyone is right eye dominant. Just blink your eyes alternately and you’ll see the jump yyAlbert described. Second, my interocular (eye separation) distance is 10 cm. The distance from my eye to my thumb (arm in front, not to the side) is 70cm. Someone commented on using the arm-eye ratio instead so in my case the multiplier would be 7. I’ll have to do some field testing but I really like this rule of thumb and appreciate your article.
When I saw the title of this article I figured it was trigonometry related, but I could only figure that you knew the angles, and you can’t solve for sides without knowing at least one side. It didn’t even occur to me to use the distance between your eyes as the known side. You could get some pretty accurate measurements just using that trick, although it’s not quite the same as this one. I remember being a kid and finding it neat that by alternating which eye was open, it would make it look like things had moved. But I never thought about it any further until perusal this article.
I’ll give this a try, but you’re still having to guess/estimate the difference in distance between left & right eye view. The farther the object the more room for error there will be. I’ve found with enough practice I’m able to reckon distance to an object within a couple hundred meters fairly well. Beyond that it doesn’t really matter in most situations.
If you also have an elevation map, you can use nearby mountain peaks, to roughly estimate how many days it will take to travel that distance. *Take note, if you are using a trail, or bushwhacking, those times of travel will be greatly different. But if you’re out there with a map, and walking to the nearest mountain peak, you probably already know this. >If you are new to backcountry travel, and deciding on what to put in your pack, or what to leave behind, a compass, and a map of your surroundings are a few things that are certainly worth the weight to carry.
This is so cool. I feel experiments coming on. Also, to determine the direction of a slow- moving cloud or storm you can close one eye and line up an object – a tree branch as example – with the cloud or storm. I frequently use “natural” methods of measurement, comparing object with object without using a measuring tape, or discretely marking size of on my hand or arm – I don’t want to use my ruler in a store and get accused of stealing it!
It might be a little easier to estimate a smaller distance in the horizon, perpendicular to your line of sight, than a longer distance between you and an object, but it all still rests on your estimate. If you are good at estimating one, you’ll be good as well at estimating the other. I’ve never felt I needed such tricks to estimate the distance of an object and I doubt it is going to improve anyone’s estimates. It’s hard to imagine a situation where this can help, but it is curious nonetheless.
This is because the ratio of distance between both eyes and distance from your nose to you thumb is 1:10. Mathematically, if we draw a line from our left eye through thumb to right side of view point. and one more line right eye through thumb to left side of view point, it will make two similar triangles. i.e. the ratio of sides of both triangles is same.
How do you know that your thumb appearing to move that much is 2 meters? Do you have to test it out on some known distances, kind of like figuring out how long your paces are? If you hold your thumb out arm’s length and look through each eye, your thumb will always seem to move the same amount. If you’re looking at a mountain peak in the distance, what would that tell you about the distance of the mountain peak? I think I must have missed something …
You need to explain why “multiply by 10”, because it is important! The distance between your eyes is – say – 6 cm (60 mm). To use this method the distance from your eyes to your thumb must be around 10 times longer, i.e. ~60 cm. So! It is important how you hold your arm when you looking through your thumb (or stick) to the distant objects. You cannot hold your arm “just like that” like in the article (arbitrarily bent in your elbow joint or turned to a side). You need to take the position when eyes-to-thumb distance is about 10 times your optical RC and also hold it and look right in front of you. In my case RC is 60mm, while the fully extended arm is 700mm, so I need to adjust. Also, you can hold your eyes both open – so you will see two images of your one thumb at once while looking at the distant object.
You my friend I’m sorry there’s not a word I can think to use that would describe the joy of what I just learned from you I love learning little stuff like that and then going out and testing it cuz I’m wanting to get an in the process of getting to where I can go hiking and things of that nature anyway awesome thank you so much
Here’s the math of it. the triangle between your pupils and your thumb is a set thing. The average pupilary distance is 63mm (or about 2.5 inches). The average person can reach about 2 feet (24 inches… but we’ll call it 25) in front of their face, and generally speaking, even with tall or short people, these numbers remain reasonably proportional. So that means (through angular geometry) that for every 25 inches forward you follow the line coming from our right pupil, if you follow the line coming from your left eye the same 25 inches, it will land at a spot the same distance forward, but 2.5 inches to the right… and this too scales. If you are looking 100 inches ahead of your thumb (4x the distance from your eye to your thumb) and you put a flag at the 100 inch spot on your left and right eyelines separately, you will see that the flag that’s on your left eyeline will be 10 inches (4x the distance between your pupils). This holds true no matter the scale. Why does this help though? Because as humans we are much much much better at discerning the distance between 2 objects that are perpendicular to our line of sight than any other possible angle. Also, humans are more accurate in measuring small distances than large ones.
another way to consider this rule is that there are two distances you are considering here. the distance your thumb appears to move sideways from your target, and the distance from your body to the target. more or less, the distance from your body to target will always be 10 times the distance that your thumb appears to move sideways from your target. all this is really doing is changing your guess of distance to a sideways guess instead of a range guess. this is really nice though be cause its way, WAY easier to guess how far something has moved sideways. imagine if you see a deer in the distance and it takes a few steps to the side in your view. you will have a very good idea of how far the deer went. if the deer walks directly towards or away from you, it will not be quite such a good guess. the real nice trick to this method is when you KNOW the distance of something near your target. this is most often the width of a road. i have used the method to survey an unmapped road to great accuracy. if you are standing on a road and there is a tree way in the distance on the same road, you first pace the road right where you are. then you do the thumb trick with the side of the road in the distance as your target. you then see how far your thumb has moved sideways, and you can count that in terms of how many road-widths it moved. maybe it move 3 times the width of the road in the distance. this means you do some simple math of (3 road-widths at the target * x paces per road width * 10) = paces to the target.
Every aircraft has a black box which is very strong and doesn’t easily gets damaged even incase of an aircraft crash. It records every detail happening inside and around aircraft . Eg: air pressure inside and outside aircraft, oil inside oil tank, humidity, wind speed, wind direction, aircraft altitude, aircraft speed, conversation by pilots etc. This will reveal whether the aircraft crashed on some mountain or whether it was hit by missile or rocket.
This works because of proportionality of similar objects, in this case right triangles. If you assume the distance between your thumb and eye is about ten times the distance between your eyes, then it works perfectly. In general, it’s approximate because the distance between our eyes is about 2.4 inches and the distance between our eye and thumb (held out in front) is about 24 inches (ten times the distance between our eyes).
There’s a fundamental flaw in this. Even though it may work, it’s contingent on you being able to estimate the left right distance that the image of your thumb moves. And the fundamental problem with that step is when you’re trying to estimate the distance between objects that you can’t tell the scale of. You might be trying to estimate the distance between a tree and a hill, or between a boulder and a valley, or between a building and a bridge, and unless you know how big the bridge is, or how big the boulder is, or how big the tree is, you’ll have a really poor time accurately estimating the distance between them.
Is it easier to guess the distance between thumbs with something that is 200m away though? Or just guess the distance to the thing. You really did a great job of explaining this on a article though. The camera work and showing the perspective when you were facing the camera vs facing the object clarified it.
I used trigonometry amd a ruler to do sth like that, but its not easy to measure because eyes are like 10 cm away from each other, and when you need to see how far is sth more than 5 meters away you simply cannot see the coresponding angle and use the equation on the triangle … Its better to build a 50cm wide tool with 2 aiming devices in order to mark the angle and use : x = tanθ*50 and find with better accuracy the distance in cm and later convert to meters
This technique is belongs to India…….. Britishers got this technology from India. The person who surprised Britishers by this technology called “Pathani Samanta,lives in Odisha a state of India.That time Pathani Samanta surprised Britishers when he told them the accurate height of a mountain by using two sticks only ….. We Proud to be Indian….. My India is Great….🇮🇳 Jai Hind ✊✊✊ Jai Bharat ✊✊✊
I have one for you! How much time do I have until the sun sets? In late afternoon? Extend your hand at arms length turn your hand so that finger are 90 degrees to your arm. Place your little finger on the horizon, if the sun is still above your fingers add finger from other hand to fill the gap between the sun and your lower fingers. Each finger is worth 15 minutes before sunset. 😁🛫
I understand how it works, but you showed examples that were quite close with pretty much known sizes of objects. The tree truck is about 0.5 meter and such towers are about 20 meters. Short distances are easy to just estimate the distance by eye. How accurate of a reference distance can you glean from looking at a the tree covered hillside several Km in the distance? Which would be a more realistic distance of which you would need to use this method to approximate the distance.
How long should be the distance between of your thumb and an eye ? because if i bring it closer to the eye, and then do measurements, the difference of results between the left/right eyes will be much larger, than if my thumb is at its maximal distance that my hand allows it. So i think it doesn’t work, because each human will measure it differently due to individual length of the hands and preferences of measurement.
what I do not understand, is where the initial measurement of “two meters” derived from. Are you saying the estimated distance of the point of perspective between the right eye, and the left eye’s perspective.. estimated to be two meters distance? so you multiply this random distance by 10, giving an computed extimated
when you figure the movement is 2m or 20m you’ve already measured the distance. because – if I’m understanding the instructions right – you’re saying the tree, for example, seems to have moved 20 metres sideways. Well why did you say 20 m and not 200 metres? Because you are applying a distance ‘correction’. At that distance you judge that much ground horizontally would be about 20 m. Kinda like looking at two hilltops on the horizon and judging how far apart they are.
Very Good Idea. ! But my point is why we have not come up with some elec. sensing device yet which can give us a pretty close estimate of the distance. Whenever I sit down & watch the mountains near by this thought of distance is in my mind. ! After some rea. done & the product comes in the market then Hindu. {brahmin} will say it is already in the vedas. Ah ! ah.! ah.!
Ok asking a dumb question. I get all of this except the first guesstimate of 2 meters and 20 meters in your examples. The very first measure you calculate by your eyes’ differences. How do you get “2 meters” from what appears to be several inches at most? Between your eyes’ vantage points, I mean. All the rest I get. Lol I’m slow witted I guess. Thanks, this was great, and I know this is a year old. Hoping you might notice this and reply so I can grasp that part. 🙂
Suppose it is before sunset, but you want to know the time until the sun goes below the horizon. Hold out your hand with your index finger resting just on the horizon. Count the number of fingers up until the sun. Each finger is supposed to be about fifteen minutes (give or take a bit depending on how fat or skinny your fingers are).
when I was a Little Boy, my father told me this, but he said they used it to know where a bomb was going to hit, he said if it moves behind a bullet then it will miss you, if it falls in front of the bullet it will hit in your area. he used this in WW2. I am 79 now and remembered this theroy,, he came home safe so could be a lot of truth in this.
So to check the 10x measurement I went to my mirror & measured with a Ruler my inter pupil distance. Important not to use a tape measure as you can poke yourself in the eye with the hook. All kidding aside I measured 2.7 inches. Just a hair less than 3/4″ & then measured the bridge of my nose to my thumb as near to the edge you would reference point for this trick. 26.5″. Pretty dang close to the 10:1 ratio I would say.