Quantitative and Qualitative Data

Quantitative data records amounts, counts, or measurements on a scale where arithmetic makes sense: minutes waited, tickets created, money paid. Qualitative data records categories, descriptions, and accounts: which channel, what a customer wrote, why an agent thinks tickets are slow. The distinction is about what the values mean, not about whether they are stored as numbers or words, and neither kind is automatically objective or subjective.

A number is not always a quantity

A category code of 1, 2, or 3 for billing, delivery, and account is a label stored as a digit; its average is meaningless and its sort order is an accident of configuration. A survey answer of 2 on a five-point agreement scale is an ordered choice: 4 is not twice 2, and the step from 1 to 2 is not known to equal the step from 3 to 4, so report how many chose each level rather than a mean. A timestamp is numeric and precise, yet whether an automatic acknowledgement counts as a reply was a human definition written into the data dictionary. Every quantitative value carries the choices of whoever defined, recorded, and derived it.

Qualitative evidence is evidence with its own rules

Free-text comments and interviews explain mechanisms that counts cannot: three of eight agents mention waiting for the finance team. That is a hypothesis for the ticket log to test, and it is three comments, not a frequency for the team of twelve. Who was asked, who answered, how the question was worded, and how one analyst coded the answers all shape the result; statistical agencies list such response and measurement effects among the errors every survey carries.

Use the two kinds together with their roles stated: counts to say how much and how often under a written definition, accounts to suggest why and what to measure next. A vivid quotation presented as a statistic, or a mean computed on a rating scale, is the usual way the roles get confused.

Reference: Statistics Canada: Non-sampling error. Examples here are illustrative.