Summary: How many TidyTuesday posts have alt text?

Silvia scraped 7137 TidyTuesday Tweets posted between 2018 and 2021. I concatenated them into one data set. The four categories for the alt text field were

  1. Default Description - Twitter fills in “Image”
  2. Descriptive Text - the user supplied alt-text
  3. Scraping Error - the alt text could not be retrieved
  4. Alt-text unavailable due to non-static content
Characteristic AltTextCat Total
DefaultDescription DescriptiveText ScrapingError UnavailableNonStatic
Year
2018 565 (80%) 8 (1.1%) 64 (9.0%) 72 (10%) 709 (100%)
2019 1,663 (82%) 21 (1.0%) 79 (3.9%) 259 (13%) 2,022 (100%)
2020 2,861 (85%) 99 (2.9%) 105 (3.1%) 309 (9.2%) 3,374 (100%)
2021 889 (86%) 87 (8.4%) 2 (0.2%) 54 (5.2%) 1,032 (100%)
Total 5,978 (84%) 215 (3.0%) 250 (3.5%) 694 (9.7%) 7,137 (100%)

Word and character counts

Words

Words were counted using the word_count() function in the {qdap} R package, with the option to include digits set to TRUE because numbers have important meaning in describing graphs. The median word count for alt text descriptions was 23, with a range of 1 to 170. The following table presents these statistics by year.

Characteristic 2018, N = 8 2019, N = 21 2020, N = 99 2021, N = 87
wordCount
Minimum 9 2 1 1
Median 37 20 16 30
Maximum 68 68 170 164

Characters

Characters were counted using the character_count() function in the {qdap} R package, with the option to include digits set to TRUE because numbers have important meaning in describing graphs. The median character count for alt text descriptions was 121, with a range of 3 to 788. The following table presents these statistics by year.

Characteristic 2018, N = 8 2019, N = 21 2020, N = 99 2021, N = 87
charCount
Minimum 46 9 13 3
Median 174 93 74 163
Maximum 323 312 788 786