# Intelligibility and Listening Effort of Spanish Oesophageal Speech +
## 6 Conclusions  
We performed two different experiments to collect intelligibility and LE metrics for OS and HS. The first experiment, a web-based one, was used to collect intelligibility and self-reported LE metrics. The conclusions of this experiment were that speaker type (HS or OS) had an effect on both intelligibility and effort. There was significant correlation between WER and LE. Listeners familiar with OS fared the same for intelligibility as people who were not. However, they reported less effort in listening to OS than the not familiar listeners. The ASR intelligibility was poorer for OS compared to HS.  
The second experiment was to measure listening effort for HS and OS in a laboratory setting. The conclusions were that even if the intelligibility of OS was close to HS, there was a considerable difference in LE.  
LE obtained through these experiments is based on the listener's own interpretation of 'effort involved in listening'. Our future task involves the analysis of EEG data, which is a direct physiological measure, and looking into its correlation with this self-reported measure of LE.  
Another ongoing task is to build an OS restoration system aimed at better ASR and HSR intelligibility and low LE. The methods used in this study will be used to evaluate the outputs of this system.  
Both HSR intelligibility and ASR intelligibility play different but important roles in OS evaluation. While improved HSR would enable better human-human interactions, an improved ASR performance would enable better human-machine interactions (e.g., digital voice assistants). Lower LE would also contribute towards improved communication with fellow humans. The evaluation of all these three metrics provides an all-round understanding of OS speech perception.  
The following are available at [[http://www.mdpi.com/2076-3417/9/16/3233/s1](http://www.mdpi.com/2076-3417/9/16/3233/s1)]([http://www.mdpi.com/2076-3417/9/16/3233/s1](http://www.mdpi.com/2076-3417/9/16/3233/s1)), Excel SI: Intelligibility and Listening Effort of Spanish Oesophageal Speech.  
conceptualization, S.R., I.H., E.N., A.W.; methodology, S.R., I.H., E.N., A.W.; software, L.S., S.R.; validation, S.R.; formal analysis, S.R.; investigation, S.R., I.H., E.N., A.W.; resources, S.R., I.H., E.N., L.S., A.W.; data curation, S.R.; writing-original draft preparation, S.R.; writing-review and editing, S.R., I.H., E.N., A.W.; visualization, S.R.; supervision, I.H., E.N., A.W.; project administration, I.H., E.N.; funding acquisition, I.H.  
**Funding:** This project was supported by funding from the EUs H2020 research and innovation programme under the MSCA GA 67532*4 (the ENRICH network: www.enrich-etn.eu), the Spanish Ministry of Economy and Competitiveness with FEDER support (RESTORE project, TEC2015-67163-C2-1-R) and the Basque Government (DL4 NLP KK-2019/00045, PIBA_2018\(1\)0035 and IT355-19).  
**Acknowledgments:** We would like to thank [PERSON], [PERSON], [PERSON], and [PERSON] for helping with the listening test setup of our second experiment  
**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.