In a scientific investigation, what does the term "quantitative data" refer to?
Quantitative data refers to the logistics of an experiment: numbers and measurable data.
Length, height, width and how much a temperature has increased all classify as quantitative data.
The counterpart, qualitative data, is the description of data: the five senses generally fall under this category: smell, feeling, taste, look.
Take a painting, for example. The quantitative data would be the canvas' width or the weight of the entire painting. The qualitative data would be the color of the painting or what it feels like (texture).