Abstract The relationship between objective properties of speech and perceived pronunciation quality in read and spontaneous speech was examined. Read and spontaneous speech of two groups of non-natives was scored for pronunciation quality by human raters. The same material was analyzed by means of a continuous speech recognizer to calculate six temporal measures of speech quality. The results show that temporal measures of speech are strongly related to pronunciation quality, in both read and spontaneous speech. Not all measures are as effective to predict pronunciation quality in spontaneous speech as they are in read speech. 1 Introduction Recently, attempts have been made at developing automatic pronunciation tests by using continuous speech recognizers. These studies have revealed that automatically obtained measures of speech quality are strongly correlated with scores assigned by human experts. Most of these studies concern read non-native speech. In this poster we explore whether this also holds for spontaneous non-native speech. 2 Goal Exploring the relationship between automatic temporal measures and perceived pronunciation quality in read and spontaneous speech. 3 Method Two independent experiments were conducted: Experiment 1: read speech Experiment 2: spontaneous speech These experiments varied in: - speakers - speech mode: read versus spontaneous - expert raters 4 Speakers Experiment 1 60 non-native speakers (NNS) speakers varied in: - mother tongue - gender three proficiency levels (PLs): PL1, PL2, PL3 Experiment 2 57 non-native speakers (NNS) speakers varied in: - mother tongue - gender two proficiency levels: lower proficiency (LP) higher proficiency (HP) 5 Speech material Experiment 1 read speech all speakers read the same sets of 10 phonetically rich sentences Experiment 2 spontaneous speech LP and HP answered two different sets of 8 questions HP task was more cognitively demanding Experiment 1 three rater groups: 3 phoneticians (ph) 3 speech therapists (st1) 3 speech therapists (st2) speakers divided over the three raters in each group raters did not receive any specific instructions 7 Rating scales The expert raters judged the speech material on the basis of the following four scales: - Overall Pronunciation (OP) scale 1..10 - Segmental Quality (SQ) scale 1..10 - Fluency (FL) scale 1..10 - Speech Rate (SR) scale -5..+5 For each speaker one score on each of the four scales was calculated. 8 Automatic scores An off-the-shelf CSR was used. A forced Viterbi alignment was applied to calculate the following scores: art (articulation rate) = #phones / tdur1 ros (rate of speech) = #phones / tdur2 ptr (phonation / time ratio) = 100% * tdur1 / tdur2 mlr (mean length of runs) = average #phones between pauses #ps (# pauses (>.2 s) per second) = #pauses / tdur2 mlp (mean length of pauses (>.2 s)) tdur1 = total duration without pauses tdur2 = total duration with pauses