Last semester, as I spend untold hours editing the closed captioning automatically generated by YouTube on the math videos on my YouTube channel, I got a crash course on the capabilities and limitations of this system. This crash course was perhaps not legally necessary but extra work that I took on because a student with a hearing impairment was enrolled in my class, and I wanted to ensure that the review videos that I provide to my students were accessible to him also.

I think the resources offered by my university are fairly typical to ensure that instructors are able to reach all students and not just those who don’t have audio/visual impairments. After discussions with the cognizant people at my university, I’ve made a few conclusions:

- Mostly by accident, my videos are ADA compliant since I made the decision to both write out the solutions and also talking through the solutions.
- While the automatic closed-captioning provided by YouTube may be minimally compliant with ADA, I’m not sure that a student with a hearing impairment could always follow the transcriptions due to a number of errors.
- Aside from punctuation, capitalization, and the occasional homonym (e.g.,
*right*vs.*write*), YouTube does a pretty good job at transcribing ordinary speech. - Naturally, YouTube’s automated closed-captioning is not to blame when I don’t enunciate clearly, have a rabbit trail of thought but then have to backtrack, use poor grammar, make a outright mistake, etc.
- However, YouTube seems to have a lot of difficulty providing automatic closed-captioning of mathematical speech.

Fixing these transcription errors took an ** awful **lot of time. I don’t want to know how many hours I devoted to fixing the 120 or so videos (each video is about 3-10 minutes long) recorded so that my hearing-impaired student could have full access to my class. About halfway into this project of fixing the closed-captioning errors, I started writing down some of the closed-captioning errors. I wish I had thought to do this near the start, but oh well.

Phonetically, I can understand why most of these errors were made. But these mistakes really shouldn’t have happened. Here are my favorite howlers that I recorded, showing both what I said and what YouTube thought I said.

- “931,147,496” became “930 1,000,000 147,000 496”
- “,” pronounced “ intersect ,” became “A inner sexy”
- “arithmetic” became “rhythm sick”
- “capital ” became “Catholics”
- “cardinality” became “carnality”
- “divisible by 5” became “visited his wife live” (I have no idea how that happened)
- “” became “eat ooh the x”
- “for succinctness” became “force the sickness”
- “,” pronounced “ choose ,” became “and shoes and”
- “set containing” became “second taining”
- “” became “squirt tuna”
- “two ways in” became “too wasted”
- “what latex f$ of 3,” became “whateva 3”
- , pronounced “ is in ,” became “sexism be”
- , pronounced “ is in and ,” became “x is Indiana see”
- , pronounced “ is in ,” became “excellency”

Here’s the complete list of howlers that I recorded for posterity. If I’ve learned nothing else, it’s that I need to be more proactive about ensuring the mathematical accuracy of closed-captioning for my YouTube videos.

4 | for |

857 | a 50 7 |

1232 | 1230 two |

4761 | 4760 1 |

19,999 | 19,000 999 |

46,376 | 40 6376 |

123,552 | 120 3,552 |

5,565,120 | five million 565,000 120 |

931,147,496 | 930 1,000,000 147,000 496 |

2d sent | |

28 | |

one too | |

12 juice 4 | |

16 choosing | |

surplus one mix for | |

4 2 0 | |

four twos k | |

49 she’s 5 | |

52 six | |

a choose to | |

A inner sexy | |

a intersecting | |

a you be | |

a UNC | |

a you will see | |

a proof | approved |

a compliment | |

asa by | |

all multiples of | almost visit |

an element of | known the debate |

an element of | normal today |

and divisible | and as above |

and positive 50 | + + 50 |

and tens | intense |

and would let this be 3 | andrew lippa p3 |

arithmetic | earth to |

arithmetic | rhythm sick |

s | ace |

but not | be but not si |

b in a sexy | |

if | beef |

bijection | bi CH action |

bijection | bite jection |

bijection | by dejection |

bijection | by ejection |

bijection | by jection |

bijection | by Junction |

both sets | both says |

capital X | Catholics |

cardinality | carnality |

Cartesian | car to shull |

codomain | code Amin |

coordinate | cordon |

coordinate | court |

coordinates | corners |

coordinates have | cort in sap |

cosine | cosign |

disjoint | destroyed |

divisible by 5 | visited his wife live |

eat ooh the x | |

element of A | illness of A |

element of A | mellow today |

element | that Windex |

elements | of us |

empty | MQ |

descent | |

intercept | |

equal | able |

exponent | x1 |

factored | acted |

factorial | fact welders |

fill in | film |

flipping four coins | philippine for coins |

for succinctness | force the sickness |

hence in | Hanson |

eye | |

aye | |

If I divide by 15 | If I / 15 |

in | nae |

in there | a bear |

infinite | if an |

infinite | imp an |

infinite | infant |

into five | in 2 5 |

s | ice |

j choose arms | |

th | cave |

th | kate |

likewise | lakh wise |

and shoes and | |

th row | nth throw |

one-to-one | 121 |

onto | on 2 |

our shoes are | |

to | art at |

to | already |

are too | |

our too | |

‘s | hours |

same row | samro |

second coordinate | sec cornered |

set containing | second inning |

set containing | second taining |

set containing | seconds hanging |

set containing | secretary |

set containing 1 | second anyone |

since has | say has |

sixth one | six-month |

square | swear |

score 2 | |

squirt of tuna | |

team A | teammate |

term in it | terminate |

than zero | gloves are off |

that’s chosen | that’s Showzen |

then | the next |

therefore | there for |

this entry in | the century plus |

to the | decay |

two are | to are |

two ways in | too wasted |

union | you need |

up here | pier |

what | whateva 3 |

will be 4 | will before |

with | finials 4 |

would subtract | was attract |

writing | riding |

is | extras |

is in | exiting |

is in | x as a native |

is in | x is nay |

is in | sexism be |

is in and | x is Indiana see |

is in | excellency |

is in | X’s and see |

next to | |

text too | |

coordinate | export |

why | |

wine | |

is greater than or | wider |

s | wise |