Abscissa and ordinate is the distance between the projection and the origin of the axis, and whose sign is given by the location on the projection relative to the origin (before: negative; after: positive). Usually these are the horizontal and vertical coordinates of a point in a two-dimensional rectangular Cartesian coordinate system. The terms can also refer to the horizontal and vertical axes respectively (typically "x"-axis and "y"–axis) of a two-dimensional graph. An ordered pair consists of two terms—the abscissa (horizontal, usually "x") and the ordinate (vertical, usually "y")—which define the location of a point in two-dimensional rectangular space. Though the word "abscissa"
Paired data medicine. In this case the data is "paired" as it is likely the blood pressure "after" giving the medicine will be related to the blood pressure of that patient "before" the medicine was given. The statistical tests used to compare sets of data have been designed for data that is either paired or unpaired and it is important to use the correct test to prevent erroneous results. Examples of tests for unpaired data: Examples of tests suitable for paired data: Paired data Scientific experiments often consist of comparing two or more sets of data. This data is described as unpaired