Summary: How many TidyTuesday posts have alt text?

Silvia scraped 6443 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 302 (89%) 26 (7.7%) 1 (0.3%) 9 (2.7%) 338 (100%)
Total 5,391 (84%) 154 (2.4%) 249 (3.9%) 649 (10%) 6,443 (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 93, with a range of 1 to 170. The following table presents these statistics by year.

Characteristic 2018, N = 81 2019, N = 211 2020, N = 991 2021, N = 261
wordCount 37, 9-68 20, 2-68 16, 1-170 22, 2-109

1 Statistics presented: Median, Minimum-Maximum

Characters

The maximum character count for Twitter alt-text is 420. The median character count for all years is 93, with a range of 8 to 788. The following table provides these statistics by year:

Characteristic 2018, N = 81 2019, N = 211 2020, N = 991 2021, N = 261
wordCount 37, 9-68 20, 2-68 16, 1-170 22, 2-109

1 Statistics presented: Median, Minimum-Maximum