Among various structures in Stata for cycling through lists (whether lists of variable names, numbers, or arbitrary strings) are foreach and forvalues, introduced in Stata 7 in 2001, and for, introduced in Stata 3.1 in 1992, and revised in 5.0 (1997) and 6.0 (1999). Typically, each member of the...

The Stata program triplot produces a triangular plot of three variables with constant sum. Most commonly, three fractions or proportions add to 1, or three percents add to 100. The constant sum constraint means that there are just two independent pieces of information. Hence, it is possible to...

Graded data are those possessing an inherent order but falling short of a metric scale. Examples are opinions on a five-point scale, such as strongly disagree, disagree, neutral, agree, strongly agree. Graded data are, like ranked data, one kind of ordinal data. They are common in many fields,...

Circular data are a large class of directional data, which are of interest to scientists in many fields, including biologists (movements of migrating animals), meteorologists (winds), geologists (directions of joints and faults), and geomorphologists (landforms, oriented stones). These examples...

The Stata Technical Bulletin (STB ) started publication in March 1991 and ceased in May 2001, after 61 bimonthly issues. It has been succeeded by the Stata Journal (SJ), of which two quarterly issues have so far appeared, 1(1) for the last quarter of 2001 and 2(1) for the first of 2002. Although...