ymeas

Ymeas is a convention used in data analysis and modeling to denote the measured values of a dependent variable Y. It is not a formal mathematical symbol but a common shorthand found as a column name in datasets, variables in scripts, or keys in data formats. The exact meaning depends on the domain, but it typically contrasts with predicted or simulated values.

In model fitting and evaluation, ymeas holds observed data that are compared to model predictions (often denoted yhat or ypred). Residuals are computed as ymeas minus yhat. Ymeas is also used in calibration workflows to adjust parameters so that predictions align with observed outcomes, and in reporting to distinguish observed results from simulated results.

In practice, ymeas appears in programming languages and data formats as a variable name, column label, or JSON field. It is commonly paired with x or xdata for the independent variable. The exact interpretation relies on documentation; some domains may use yobs, ytrue, or ydata for similar meanings.

See also residual, model fitting, calibration, and data naming conventions. Note that ymeas is not a universal standard, and its meaning can vary between projects, so consulting project-specific documentation is advisable.