13. A computer-implemented method for scoring a spontaneous speech sample to characterize speaking proficiency, the method comprising: retrieving a scoring model, wherein the scoring model has been trained using speech features that include a previously assigned score for a training speech sample, wherein the previously assigned score is assigned by a human rater based on the training speech sample; wherein the scoring model is independent of speech recognition accuracy associated with the spontaneous speech sample; and assigning a numeric speaking proficiency score to a received spontaneous speech sample using the scoring model using a computer.
13. A computer-implemented method for scoring a spontaneous speech sample to characterize speaking proficiency, the method comprising: retrieving a scoring model, wherein the scoring model has been trained using speech features that include a previously assigned score for a training speech sample, wherein the previously assigned score is assigned by a human rater based on the training speech sample; wherein the scoring model is independent of speech recognition accuracy associated with the spontaneous speech sample; and assigning a numeric speaking proficiency score to a received spontaneous speech sample using the scoring model using a computer. 14. The method of claim 13 wherein the one or more speech features comprise one or more of the following for each spontaneous speech sample: a lexical count; a fluency measure; a rate of speech measure; and a speech sample utterance duration.