TedTest

From the Ted Talk by Matt Anticole: What's the difference between accuracy and precision?

Unscramble the Blue Letters

As the story goes, the legendary marksman William Tell was forced into a cruel challenge by a curprot lord. William's son was to be executed unless William could sohot an apple off his head. William succeeded, but let's imagine two variations on the tale. In the first variation, the lord hires a bandit to steal William's tsrtuy crossbow, so he is frcoed to borrow an inferior one from a peasant. However, the borrowed crossbow isn't adjusted perfectly, and William finds that his practice shots ctselur in a tight spread beneath the bullseye. forlnettauy, he has time to crocert for it before it's too late. Variation two: William begins to doubt his skills in the long horus before the cghlaelne and his hand develops a tremor. His practice sthos still cluster around the alppe but in a random pattern. Occasionally, he hits the apple, but with the wblboe, there is no guarantee of a bullseye. He must settle his nruevos hand and restore the certainty in his aim to save his son. At the heart of these variations are two terms often used interchangeably: accuracy and precision. The dosiicttinn between the two is actually citarcil for many scientific endeavours. Accuracy iolnevvs how close you come to the correct result. Your accuracy improves with tools that are calibrated ccorlerty and that you're well-trained on. pcsirioen, on the other hand, is how consistently you can get that rulset using the same mtheod. Your precision improves with more finely incremented tools that require less estimation. The story of the soletn crossbow was one of precision without accuracy. William got the same wrong result each time he fired. The variation with the shaky hand was one of accuracy without precision. William's bolts clustered around the correct result, but without certainty of a bullseye for any given shot. You can probably get away with low accuracy or low precision in everyday tasks. But engineers and rcrhaseeres often rqiuree accuracy on microscopic levels with a high certainty of being right every time. Factories and labs increase precision through better equipment and more detailed procedures. These improvements can be exesvinpe, so marngeas must diedce what the acceptable uncertainty for each prejoct is. However, investments in precision can take us beyond what was poiluevsry possible, even as far as Mars. It may surprise you that NASA does not know exactly where their probes are going to touch down on another planet. Predicting where they will land requires extensive calculations fed by measurements that don't always have a precise answer. How does the Martian atmosphere's dntisey change at different elevations? What angle will the probe hit the atmosphere at? What will be the speed of the probe upon ernty? Computer simulators run thousands of different landing scenarios, mixing and matching values for all of the variables. Weighing all the possibilities, the computer sitps out the potential area of impact in the form of a landing eilsple. In 1976, the landing ellipse for the Mars Viking Lander was 62 x 174 melis, nearly the area of New jeesry. With such a limitation, NASA had to ignore many ietntrensig but rkisy landing areas. Since then, new iofainmtorn about the Martian atmosphere, improved spacecraft technology, and more powerful computer simulations have drastically reduced uncertainty. In 2012, the landing ellipse for the Curiosity Lander was only 4 miles wide by 12 miles long, an area more than 200 times smaller than Viking's. This allowed NASA to target a specific spot in Gale Crater, a previously un-landable area of high scientific interest. While we ultimately strive for accuracy, precision reflects our certainty of reliably achieving it. With these two principles in mind, we can shoot for the stars and be cfnoedint of hitting them every time.

Open Cloze

As the story goes, the legendary marksman William Tell was forced into a cruel challenge by a _______ lord. William's son was to be executed unless William could _____ an apple off his head. William succeeded, but let's imagine two variations on the tale. In the first variation, the lord hires a bandit to steal William's ______ crossbow, so he is ______ to borrow an inferior one from a peasant. However, the borrowed crossbow isn't adjusted perfectly, and William finds that his practice shots _______ in a tight spread beneath the bullseye. ___________, he has time to _______ for it before it's too late. Variation two: William begins to doubt his skills in the long _____ before the _________ and his hand develops a tremor. His practice _____ still cluster around the _____ but in a random pattern. Occasionally, he hits the apple, but with the ______, there is no guarantee of a bullseye. He must settle his _______ hand and restore the certainty in his aim to save his son. At the heart of these variations are two terms often used interchangeably: accuracy and precision. The ___________ between the two is actually ________ for many scientific endeavours. Accuracy ________ how close you come to the correct result. Your accuracy improves with tools that are calibrated _________ and that you're well-trained on. _________, on the other hand, is how consistently you can get that ______ using the same ______. Your precision improves with more finely incremented tools that require less estimation. The story of the ______ crossbow was one of precision without accuracy. William got the same wrong result each time he fired. The variation with the shaky hand was one of accuracy without precision. William's bolts clustered around the correct result, but without certainty of a bullseye for any given shot. You can probably get away with low accuracy or low precision in everyday tasks. But engineers and ___________ often _______ accuracy on microscopic levels with a high certainty of being right every time. Factories and labs increase precision through better equipment and more detailed procedures. These improvements can be _________, so ________ must ______ what the acceptable uncertainty for each _______ is. However, investments in precision can take us beyond what was __________ possible, even as far as Mars. It may surprise you that NASA does not know exactly where their probes are going to touch down on another planet. Predicting where they will land requires extensive calculations fed by measurements that don't always have a precise answer. How does the Martian atmosphere's _______ change at different elevations? What angle will the probe hit the atmosphere at? What will be the speed of the probe upon _____? Computer simulators run thousands of different landing scenarios, mixing and matching values for all of the variables. Weighing all the possibilities, the computer _____ out the potential area of impact in the form of a landing _______. In 1976, the landing ellipse for the Mars Viking Lander was 62 x 174 _____, nearly the area of New ______. With such a limitation, NASA had to ignore many ___________ but _____ landing areas. Since then, new ___________ about the Martian atmosphere, improved spacecraft technology, and more powerful computer simulations have drastically reduced uncertainty. In 2012, the landing ellipse for the Curiosity Lander was only 4 miles wide by 12 miles long, an area more than 200 times smaller than Viking's. This allowed NASA to target a specific spot in Gale Crater, a previously un-landable area of high scientific interest. While we ultimately strive for accuracy, precision reflects our certainty of reliably achieving it. With these two principles in mind, we can shoot for the stars and be _________ of hitting them every time.

Solution

shoot
risky
critical
involves
miles
apple
shots
fortunately
researchers
corrupt
ellipse
nervous
correct
expensive
confident
forced
method
precision
managers
spits
decide
trusty
distinction
information
previously
result
wobble
correctly
entry
stolen
interesting
challenge
require
cluster
hours
density
jersey
project

Original Text

As the story goes, the legendary marksman William Tell was forced into a cruel challenge by a corrupt lord. William's son was to be executed unless William could shoot an apple off his head. William succeeded, but let's imagine two variations on the tale. In the first variation, the lord hires a bandit to steal William's trusty crossbow, so he is forced to borrow an inferior one from a peasant. However, the borrowed crossbow isn't adjusted perfectly, and William finds that his practice shots cluster in a tight spread beneath the bullseye. Fortunately, he has time to correct for it before it's too late. Variation two: William begins to doubt his skills in the long hours before the challenge and his hand develops a tremor. His practice shots still cluster around the apple but in a random pattern. Occasionally, he hits the apple, but with the wobble, there is no guarantee of a bullseye. He must settle his nervous hand and restore the certainty in his aim to save his son. At the heart of these variations are two terms often used interchangeably: accuracy and precision. The distinction between the two is actually critical for many scientific endeavours. Accuracy involves how close you come to the correct result. Your accuracy improves with tools that are calibrated correctly and that you're well-trained on. Precision, on the other hand, is how consistently you can get that result using the same method. Your precision improves with more finely incremented tools that require less estimation. The story of the stolen crossbow was one of precision without accuracy. William got the same wrong result each time he fired. The variation with the shaky hand was one of accuracy without precision. William's bolts clustered around the correct result, but without certainty of a bullseye for any given shot. You can probably get away with low accuracy or low precision in everyday tasks. But engineers and researchers often require accuracy on microscopic levels with a high certainty of being right every time. Factories and labs increase precision through better equipment and more detailed procedures. These improvements can be expensive, so managers must decide what the acceptable uncertainty for each project is. However, investments in precision can take us beyond what was previously possible, even as far as Mars. It may surprise you that NASA does not know exactly where their probes are going to touch down on another planet. Predicting where they will land requires extensive calculations fed by measurements that don't always have a precise answer. How does the Martian atmosphere's density change at different elevations? What angle will the probe hit the atmosphere at? What will be the speed of the probe upon entry? Computer simulators run thousands of different landing scenarios, mixing and matching values for all of the variables. Weighing all the possibilities, the computer spits out the potential area of impact in the form of a landing ellipse. In 1976, the landing ellipse for the Mars Viking Lander was 62 x 174 miles, nearly the area of New Jersey. With such a limitation, NASA had to ignore many interesting but risky landing areas. Since then, new information about the Martian atmosphere, improved spacecraft technology, and more powerful computer simulations have drastically reduced uncertainty. In 2012, the landing ellipse for the Curiosity Lander was only 4 miles wide by 12 miles long, an area more than 200 times smaller than Viking's. This allowed NASA to target a specific spot in Gale Crater, a previously un-landable area of high scientific interest. While we ultimately strive for accuracy, precision reflects our certainty of reliably achieving it. With these two principles in mind, we can shoot for the stars and be confident of hitting them every time.

Frequently Occurring Word Combinations

ngrams of length 2

collocation	frequency
landing ellipse	3
practice shots	2

Important Words

acceptable
accuracy
achieving
adjusted
aim
allowed
angle
answer
apple
area
areas
atmosphere
bandit
begins
beneath
bolts
borrow
borrowed
bullseye
calculations
calibrated
certainty
challenge
change
close
cluster
clustered
computer
confident
consistently
correct
correctly
corrupt
crater
critical
crossbow
cruel
curiosity
decide
density
detailed
develops
distinction
doubt
drastically
elevations
ellipse
endeavours
engineers
entry
equipment
estimation
everyday
executed
expensive
extensive
factories
fed
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finely
fired
forced
form
fortunately
gale
guarantee
hand
head
heart
high
hires
hit
hits
hitting
hours
ignore
imagine
impact
improved
improvements
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increase
incremented
inferior
information
interest
interesting
investments
involves
jersey
labs
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lander
landing
late
legendary
levels
limitation
long
lord
managers
marksman
mars
martian
matching
measurements
method
microscopic
miles
mind
mixing
nasa
nervous
occasionally
pattern
peasant
perfectly
planet
possibilities
potential
powerful
practice
precise
precision
predicting
previously
principles
probe
probes
procedures
project
random
reduced
reflects
reliably
require
requires
researchers
restore
result
risky
run
save
scenarios
scientific
settle
shaky
shoot
shot
shots
simulations
simulators
skills
smaller
son
spacecraft
specific
speed
spits
spot
spread
stars
steal
stolen
story
strive
succeeded
surprise
tale
target
tasks
technology
terms
thousands
tight
time
times
tools
touch
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trusty
ultimately
uncertainty
values
variables
variation
variations
viking
weighing
wide
william
wobble
wrong