Understanding Numbers, Data, and Visualizations

Posted on Feb 28, 2025 in Mathematics

Writing About Numbers

1. Use Miller’s ‘W’s’ to give context

  • ‘The Ws’: what, when, where, who.
  • ‘Relevance, simplicity, plausibility’
  • Take care with jargon or technical language
  • Interpret and/or provide analogies to explain numbers

2. Use the GEE method to write about patterns

  • Generalise, Example, Exception

3. Prose, table or chart? Consider

  • Extent and complexity of the information
  • Audience
  • Story: is the overall pattern or particular values?
  • Attention: what is most important?

Describing Data

li> <li>Turning life processes into

A threat to, or modification of, our concept of autonomy A giving up or taking of ownership rights over data Extraction of data for the benefit of particular (Western, but also increasingly global capitalist) interests “In normal times, Google Classroom- and other virtual classroom tools like it- change the entire classroom dynamic. Homework isn’t lost in the recesses of lockers and backpacks; its turned in direct from the kitchen table. Snow days don’t build up into sweaty, wasted June days; students and teachers can work from home, using collaborative tools

Data Analysis Info

  • Data visualisation does rhetorical, communicative work, not just a reflection of ‘facts’
  • Text as data is shaping how language and information can be used, with major social, cultural and environmental implications.
  • Datafication transforms life in positive and negative ways. Privacy issues are a major aspect of this.

Measures of Central Tendency

  • Mode: the most frequent value in a sample
  • Median: the middle value in a sample. If there are an even number of values, find the mid-point between the two middle values
  • Mean: the arithmetic is the sum of all values in a sample, divided by the number of values

Measures of Variability

  • Range: the difference between the highest and lowest values in a sample
  • Quartiles:
  • The upper quartile is the values where 25% of values are higher, and the 75% are lower
  • The lower quartile is the value where 75% of values are higher, and 25% are lower
  • Think of quartiles like another ‘median’ for each half
  • Variance: take the difference between each value and the sample mean, square it, sum all the results, and divide by the number of values minus one. Units are squared eg no. of characters squared
  • Standard deviation: the square root of the variance. The standard deviation (SD) tells us the size of the ‘average’ difference from the mean, in characters