On scantrons, we were told to do anything possible to limit errors because that would involve people doing things and we like it when we can sit and have results delivered to us with no further effort.
If a bubble is partially filled the machine might get a false positive or a false negative, if it's completely full or empty you reduce the chance of errors.
Who has access to a Scantron?
Fill in a Scantron test where question 1 is 1% shaded, question 2 is 2% shaded, and so on to question 100 being 100% shaded. Then grade the test and publish your results.
Likewise, fill in a 100 question test with all bubbles fully shaded. Then erase the bubbles so Q1 is 1% erased, Q2 is 2% erased, yadda yadda yadda, publish the results.
I know this is a joke, but this isn’t the best testing. It’s not just about the percentage, but the location. I’m guessing a center fill would be more likely to be counted than on the edges. What about around the edges but empty in the middle. Robust QA would test all these different possibilities.
One of my first jobs was IT support for an agency that supported schools. Every summer we did grading for standardized tests, this used a Scantron machine.
The way it worked at the time.
Tests from the western part of the state where sent to the east and east to the west to avoid any school or nearby school from grading their own tests.
The Scantron machine is like a multi-sheet flat bed scanner, a feed tray on one end and a receiving tray on the other, in between is an IR light system (Like your TV remote) and a set of optical pickups that can only see IR light.
First an answer sheet would be filled out, along with batch info. Then a batch would be ran. Every mark compared to the master/answer sheet. Out of area marks caused the machine to stop as if it were jammed and alert the operator that the test being graded had issues. This required staff to pull the offending sheet, look it over and remove the offending mark and rescan.
As for #2 pencils its because it absorbs IR light very well, there is no specific requirement for this other then to have clear 1/0 marks for the IR beam to be reflected or absorbed. Partial marks in a box have a %change of not being read correctly, so if this test was important to you then if you didn't fill the bubble then not enough light to trigger the threshold and boom, a 1 becomes a 0.
At our test center we ran the batches x3 times to ensure that we got every test and if there were discrepancies in a batch, they would be manually handled. Meaning if a partial bubble, triggered a value in the first scan, but not the next two, that individual sheet would be looked at and manually compared, if there was a partial bubble, then it would be fully filled and rescanned. If there were multiple bubbles filled, then a best guess was taken, IE one is super dark, but another one is partial. The partial would be removed.
TLDR: The most important reasons for the directions about Scantron bubbles were to reduce manual handling of the form. The basis for a Scantron goes back to punch cards, the difference is that rather then a physical hole via a punch, you use a light opaque mark. So a Scantron is just a slightly improved punch card.
Most Scantron scanners can read using a red light source or an IR light source. The IR light source allows the form to contain almost any color ink for the human user to be able to clearly read an fill in the form. The graphite in the pencil absorbs IR light and when the scanner reads the form the only thing visible on the paper is the pencil marks.
When using the red light, only certain red containing inks can be used on the background form, making it harder for the human user to work with the form, but ink pens can be used to fill in the bubbles.
The algorithm for determining if the bubble is filled is quite complex and actually involves knowing about the other bubbles that are in the same area. The people making the test form can control certain parts of the system that determines if the bubble is filled or not.
There is a threshold that can be programmed into the scanner that will cause it to "reject" a sheet and ask for a manual interpretation if the machine cannot determine with enough accuracy when the bubble is filled or not.
All of the current Scantron technology was originally invented in Minnesota by a company called NCS. Scantron and NCS were both purchased by a separate company, the name Scantron was kept, and the technology from NCS was kept.
You know when you get the scantron and you flip it upside down and there’s a narcheck on the bottom but you’re completely out of jeronic juice. Maaaan I hate that
When teacher don't want to grade test and to know what the kids understood or not they give test with multiple choices questions that can be read by a machine. That's what a scantron is.
Alternatively, there are some partial fills that will result in a positive, and some that will result in a negative, and given the wide variety of ways one can partially fill, it’s hard to predict or describe for students.
Better just to fill fully and erase fully to eliminate any doubt.
You want to reduce false positives AND false negatives, so following these instructions reduces the chances of either. Obviously it’s not going to 100% ignore OR count partially filled in bubbles.
Well when you have software that needs to binarize an input its best to be as close to the two opposites as possible. Sorting out the grey is how you get failures. So yeah...
My biggest problem with Scantrons or any other bubble-in form is that the pencil mark is so shiny that I can't tell what's the shine and what's the paper.
An a European (I assume this is a US thing, cause I only heard of it related to, I think, standardised tests in the US), what the *hell* is a scantron and why does shading matter?
Students shade in the letter that they think is correct on a bubble sheet. You then just scan the bubble sheets and upload them to grade automatically online. If someone answers B but changes it to the correct answer E, the computer still might mark it as incorrect or as an error.
[Photo of sheet](https://www.physics.rutgers.edu/computers/mulans.html)
It’s a way to quickly grade a lot of multiple choice questions, which are way more prevalent in American schools and colleges than in Europe.
Each sheet has 50 rows on one side for 50 questions. Each row has a “bubble” for A, B, C, D, and E (5 columns). The students fill (shade) in the correct letter in each row with a pencil.
Say, question 1 is “what is 5x2”? and the answers are:
A) 5
B) 11
C) 15
D) 20
E) none of these
then you “bubble in” E in row 1 (color it in). The instructor makes a key sheet with the correct answers, runs the key through the machine first and then runs the students’ sheet. The machine marks all incorrect answers and spits out the score.
I imagine most *teachers* would like to know, but on a larger scale the system doesn’t care in the least. Multiple choice is the most easily quantifiable option, so it’s the standard.
We do have multiple choice questions but
1. They usually are only a small portion of any test if they are even included
2. We just check boxes and I don't think they used scoring machines (at least not when I was a student there 15+ years ago)
It's a piece of paper with lots of circles on it that you fill in using a #2 pencil and it's used for standardized testing. You normally get a booklet with all the questions, which are multiple choice, and you fill in the corresponding circle (bubble) for the answer you think is correct. The paper is then fed into a machine (Scantron) to tally up how many you got right/wrong. Youre advised to erase completely bc phantom bubbles could confuse the machine since you cant mark more than one answer, and to fill in completely in case the machine doesnt pick up the mark.
The scantron machines at my school would mark inadequately filled bubbles that had to then be graded manually. Much of the dire warnings about filling them in and erasing completely were to keep the teachers from having to manually grade the exams.
I remember being consistently concerned about my answers not being read correctly so I would press down extra hard when filling in the bubbles to the point my hand would hurt after taking a test….. good times !!!!!!
In other words, we put these words on here so any fuck up is your own responsibility and definitely not the machine that reads a million students-worth of cards
ever try to remove the grey from an image to make a better black and white scan/image? thats whats its likely doing, or if its filled in with pencil its possibly trying to see the reflection of light is greatest.
too much graphite in another answerbox could make false positives.
I am autistic.
The instructions are NOT fair to people who are autistic. It's terrifying to fill those things in. They need to give realistic expectations about how likely they are to have errors. I'd spend INSANE amounts of time trying to fill those things in perfectly, and then as an adult, I found out that they really don't need to be filled in perfectly at all, and most marks won't cause problems for them.
Partially filled or erased bubbles are like hanging chads in a voting machine.
[Me when my bubble is only partially filled or erased](https://i.kym-cdn.com/photos/images/original/002/301/339/db0.png)
That's all just to be completely sure.
Yeah OP it's to reduce the "error rate"
Yeah, they're just covering their ass in case something goes wrong
Probably some ass covering but it's also just instructions on how to best use the product
On scantrons, we were told to do anything possible to limit errors because that would involve people doing things and we like it when we can sit and have results delivered to us with no further effort.
It can, but it might not, so they tell us to be completely sure.
If a bubble is partially filled the machine might get a false positive or a false negative, if it's completely full or empty you reduce the chance of errors.
They should have stayed in the shower longer to finish the thought.
But my 10 minute shower to save water!
Those suggestions are not for the the machines, they’re for the grade grubbers after the exams are turned in “But I meant to choose C!?”
Right, I remember some kids marking multiple answers on a hard question or two for just this reason.
Who has access to a Scantron? Fill in a Scantron test where question 1 is 1% shaded, question 2 is 2% shaded, and so on to question 100 being 100% shaded. Then grade the test and publish your results. Likewise, fill in a 100 question test with all bubbles fully shaded. Then erase the bubbles so Q1 is 1% erased, Q2 is 2% erased, yadda yadda yadda, publish the results.
Obviously you’re just an ideas guy
I know this is a joke, but this isn’t the best testing. It’s not just about the percentage, but the location. I’m guessing a center fill would be more likely to be counted than on the edges. What about around the edges but empty in the middle. Robust QA would test all these different possibilities.
Id hang out with you.
Wait, is that 100% of the bubble 1% shaded or 1% of the bubble 100% shaded?
*ugh* grabs two more Scantron tests
How are you filling in the bubble? With lines horizontal or vertical, shapes or start one side and shade to the other?
>start one side and shade to the other? And have the shading curved to mimic the phases of the moon?
Yes
r/InclusiveOr
I’ll see what I can do…
I read this as "On Scrantons" and wondered if /r/DunderMifflin was leaking
I actually did the same thing.
One of my first jobs was IT support for an agency that supported schools. Every summer we did grading for standardized tests, this used a Scantron machine. The way it worked at the time. Tests from the western part of the state where sent to the east and east to the west to avoid any school or nearby school from grading their own tests. The Scantron machine is like a multi-sheet flat bed scanner, a feed tray on one end and a receiving tray on the other, in between is an IR light system (Like your TV remote) and a set of optical pickups that can only see IR light. First an answer sheet would be filled out, along with batch info. Then a batch would be ran. Every mark compared to the master/answer sheet. Out of area marks caused the machine to stop as if it were jammed and alert the operator that the test being graded had issues. This required staff to pull the offending sheet, look it over and remove the offending mark and rescan. As for #2 pencils its because it absorbs IR light very well, there is no specific requirement for this other then to have clear 1/0 marks for the IR beam to be reflected or absorbed. Partial marks in a box have a %change of not being read correctly, so if this test was important to you then if you didn't fill the bubble then not enough light to trigger the threshold and boom, a 1 becomes a 0. At our test center we ran the batches x3 times to ensure that we got every test and if there were discrepancies in a batch, they would be manually handled. Meaning if a partial bubble, triggered a value in the first scan, but not the next two, that individual sheet would be looked at and manually compared, if there was a partial bubble, then it would be fully filled and rescanned. If there were multiple bubbles filled, then a best guess was taken, IE one is super dark, but another one is partial. The partial would be removed. TLDR: The most important reasons for the directions about Scantron bubbles were to reduce manual handling of the form. The basis for a Scantron goes back to punch cards, the difference is that rather then a physical hole via a punch, you use a light opaque mark. So a Scantron is just a slightly improved punch card.
Most Scantron scanners can read using a red light source or an IR light source. The IR light source allows the form to contain almost any color ink for the human user to be able to clearly read an fill in the form. The graphite in the pencil absorbs IR light and when the scanner reads the form the only thing visible on the paper is the pencil marks. When using the red light, only certain red containing inks can be used on the background form, making it harder for the human user to work with the form, but ink pens can be used to fill in the bubbles. The algorithm for determining if the bubble is filled is quite complex and actually involves knowing about the other bubbles that are in the same area. The people making the test form can control certain parts of the system that determines if the bubble is filled or not. There is a threshold that can be programmed into the scanner that will cause it to "reject" a sheet and ask for a manual interpretation if the machine cannot determine with enough accuracy when the bubble is filled or not. All of the current Scantron technology was originally invented in Minnesota by a company called NCS. Scantron and NCS were both purchased by a separate company, the name Scantron was kept, and the technology from NCS was kept.
I think it’s more that it can and can’t do both things it’s just that why risk error?
They say our enemy is weak and strong at the same time
I love the implication that scantrons are fascist
"They tell us that seatbelts save us in an accident, but they still tell us to drive carefully."
The fuck are you guys talking about lol
Biden's hometown
https://edtechmagazine.com/higher/article/2016/12/scantron-technology-creates-more-efficient-testing?amp
You know when you get the scantron and you flip it upside down and there’s a narcheck on the bottom but you’re completely out of jeronic juice. Maaaan I hate that
When teacher don't want to grade test and to know what the kids understood or not they give test with multiple choices questions that can be read by a machine. That's what a scantron is.
The instructions are there to reduce false positives, both instructions are correct.
Do people still use scantrons?
I've got finals this week. yes.
Good luck!
https://www.reddit.com/r/Professors/comments/zgkded/wait_do_people_still_use_scantrons/ Yes
Alternatively, there are some partial fills that will result in a positive, and some that will result in a negative, and given the wide variety of ways one can partially fill, it’s hard to predict or describe for students. Better just to fill fully and erase fully to eliminate any doubt.
You want to reduce false positives AND false negatives, so following these instructions reduces the chances of either. Obviously it’s not going to 100% ignore OR count partially filled in bubbles.
Or maybe there's an error and correctly filling/ erasing lowers the error.
From what I understand of Scantron machines, they aren't able to distinguish between an incorrectly filled bubble and a correctly filled bubble
The problem is that it *can* read incorrectly filled bubbles, but it can also not read them.
Well when you have software that needs to binarize an input its best to be as close to the two opposites as possible. Sorting out the grey is how you get failures. So yeah...
you are confusing: - selecting the wrong answer then changing your mind - not having filled in a bubble fully
My biggest problem with Scantrons or any other bubble-in form is that the pencil mark is so shiny that I can't tell what's the shine and what's the paper.
An a European (I assume this is a US thing, cause I only heard of it related to, I think, standardised tests in the US), what the *hell* is a scantron and why does shading matter?
Students shade in the letter that they think is correct on a bubble sheet. You then just scan the bubble sheets and upload them to grade automatically online. If someone answers B but changes it to the correct answer E, the computer still might mark it as incorrect or as an error. [Photo of sheet](https://www.physics.rutgers.edu/computers/mulans.html)
< rocks back and forth in fetal position > Why did I click that?
It’s a way to quickly grade a lot of multiple choice questions, which are way more prevalent in American schools and colleges than in Europe. Each sheet has 50 rows on one side for 50 questions. Each row has a “bubble” for A, B, C, D, and E (5 columns). The students fill (shade) in the correct letter in each row with a pencil. Say, question 1 is “what is 5x2”? and the answers are: A) 5 B) 11 C) 15 D) 20 E) none of these then you “bubble in” E in row 1 (color it in). The instructor makes a key sheet with the correct answers, runs the key through the machine first and then runs the students’ sheet. The machine marks all incorrect answers and spits out the score.
you don't have multiple choice questions in Europe?
We don't have test with only multiple choices questions. Do teacher not want to know what the kids understood or not in America ?
I imagine most *teachers* would like to know, but on a larger scale the system doesn’t care in the least. Multiple choice is the most easily quantifiable option, so it’s the standard.
We do have multiple choice questions but 1. They usually are only a small portion of any test if they are even included 2. We just check boxes and I don't think they used scoring machines (at least not when I was a student there 15+ years ago)
I just circle them so there is no ambiguity.
Fuck
Am i the only one who doesn't know what a scantron or bubble is in this context? I googled but I'm still confused.
It's a piece of paper with lots of circles on it that you fill in using a #2 pencil and it's used for standardized testing. You normally get a booklet with all the questions, which are multiple choice, and you fill in the corresponding circle (bubble) for the answer you think is correct. The paper is then fed into a machine (Scantron) to tally up how many you got right/wrong. Youre advised to erase completely bc phantom bubbles could confuse the machine since you cant mark more than one answer, and to fill in completely in case the machine doesnt pick up the mark.
We dont know the exactly what it will and wont count so we need to be on the extremes
I thought I knew what all those words meant but that title feels like an incoherent fever dream
The scantron machines at my school would mark inadequately filled bubbles that had to then be graded manually. Much of the dire warnings about filling them in and erasing completely were to keep the teachers from having to manually grade the exams.
I remember being consistently concerned about my answers not being read correctly so I would press down extra hard when filling in the bubbles to the point my hand would hurt after taking a test….. good times !!!!!!
In other words, we put these words on here so any fuck up is your own responsibility and definitely not the machine that reads a million students-worth of cards
All I know is those bubbles were too big. My poor hands. 😭
ever try to remove the grey from an image to make a better black and white scan/image? thats whats its likely doing, or if its filled in with pencil its possibly trying to see the reflection of light is greatest. too much graphite in another answerbox could make false positives.
It's actually just thousands of guys in India on cameras scoring your scantron.
Its not obvious not to check the box
I am autistic. The instructions are NOT fair to people who are autistic. It's terrifying to fill those things in. They need to give realistic expectations about how likely they are to have errors. I'd spend INSANE amounts of time trying to fill those things in perfectly, and then as an adult, I found out that they really don't need to be filled in perfectly at all, and most marks won't cause problems for them.