SPSS Log-Likelihood Analysis

I have already extracted all modal-verb tokens from two learner corpora—one tagged “Intermediate,” the other “Advanced”—and calculated their normalized frequencies (per 10,000 words). What I still need is a statistically sound comparison of those frequencies... (Budget: $10 - $30 USD, Jobs: Data Analysis, Data Management, Data Visualization, Research Writing, SPSS Statistics, Statistical Analysis, Statistical Modeling, Statistics)