Observe the arrogant attempt to control the answer with the implication that the characterization of liquidity is a settled matter instead of an area of research. One model in your favor is given in this article: http://www.sciencedirect.com/science/article/pii/S0304405X07... which says that liquidity is related to the variance of volume but is weakly correlated with volume. It does not mention depth of book, which would be "the number of shares that could be bought or sold without changing the price of a stock." There are other models, however.