In stochastic processes, chaos theory and time series analysis, detrended fluctuation analysis (DFA) is a method for determining the statistical self-affinity of a signal.
Sore throats caused by tonsillitis or streptococcus may trigger a canker sore even after the initial throat condition has subsided. Also known as an aphthous ulcer, canker sores are painful and unsightly, but they are not contagious.
Other causes of a sore throat include: 1  Allergies. Allergies to pet dander, molds, dust and pollen can cause a sore throat. The problem may be complicated by postnasal drip, which can irritate and inflame the throat.  Dryness.