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Referring to entries in the data table

EASISTAT is based around the concept that there is a table of values with all the different measured variables attached to one data object (e.g. an experimental subject) are in one row, and that they are arranged in columns according to the quantity they measure. So one column might be for temperature, another for mass, etc. and one row might be for one rock and another row for another. Thus the statistical commands essentially operate down columns rather than across rows - the mean of one rock's weight and temperature would make little sense.

In almost all commands we need to be able to tell EASISTAT which columns we want to look at and one way to do this is to type C followed immediately (no space) by a number between 1 and the number of columns there are, e.g. C1, c3, c25. We used this syntax in the example above when we said:

s c1
meaning calculate the basic statistics of all the values appearing in the first column. Occasionally we may wish to refer to a specific row - when we want to delete a certain row perhaps. To do this we type the keyword ROW followed by a space and then the number of the row we mean, e.g. row 4, ROW 29.

Every column of the table also has a label, which appears at the top of the column in the data file and when using the data editor. This would usually describe what it is that the values in that column are measures of, such as AGE or SEX. These labels can also be used to refer to the columns so that if the second column is labelled AGE then the following both mean the same thing:

SUMMARY AGE
SUMMARY C2
In the logical and arithmetic expressions described below it is necessary to refer to the values which appear in cells in different rows. The rows are looked at one at a time and then the value specified is taken from that row, so that in a logical expression c15 means "the value appearing in column 15 of the row I am currently interested in". In this context the keyword ROW (here appearing with no number after it) means "the number of the row I am currently interested in". In fact, we don't think you'll be referring to rows much and the whole thing should become fairly clear with a few examples.