My understanding of Logistic Regression is that it is actually a classifier, hence used for predicting either a categorical outcome (ie. binary or an outcome with specific labels) as opposed to a continuous outcome. I would have expected that predicting a stock price would be a continuous outcome, so I don't understand how a stock price can actually be a classification. Can someone please enlighten me?
The poor phrasing of the abstract* suggests a possible misuse of the term; I've often seen Linear Regression of the logarithm used to predict asset price movements (the idea being that asset prices tend to change by percentages of their current value, rather than by consistent nominal values).
*Full disclosure: I only read the abstract.