Efficient Voice InformationServices for Developing

Countries

Uppsala University, 29 May 2007

• Student: Pernilla NäsforsUppsala University, Sweden

• Supervisors:– Dr. Roger Tucker

The Local Language SpeechTechnology Initiative, England

– Dr. Mucemi GakuruUniversity of Nairobi, Kenya

• Reviewer: Anders BerglundUppsala University, Sweden

The Local Language SpeechTechnology Initiative

(www.llsti.org)• Information access by voice for people who

can’t access computers and the Internet• Especially good for people who are illiterate or

visually impaired• Using existing technology/devices

– Mobile usage and coverage in rural areas areincreasing rapidly and prices will decrease withincreased usage

Motives to use mobile phone

• Easy to use– Easier to manipulate a phone than e.g. a computer

and many people are already using mobile phones

• Low investment and easy to maintain– Doesn’t require Internet-connectivity and constant

power supply as computers do

• Provides information on demand– Compared to e.g. Radio, Television, Newspapers

Text-to-Speech (TTS)

• Input any written text into a computerprogram and the computer converts the textinto spoken output

• Dynamic system – no need to record newmessages

• Focus so far on technological development ofTTS in Kiswahili, isiZulu and Hindi and somespecific local languages in Nigeria and SouthAfrica

Kiswahili TTS

• TTS in standard dialect Kiunguja,suitable for Kenya, Tanzania and otherEast African countries

• First language of almost 800,000 people• Second language of 30 million rural

people

Linguistic Digital Divide

• Information and Communication Technologiesfor Development (ICT4D) was put intospotlight at WSIS 2003 and 2005.

• WSIS in Tunis 2005 recognised a linguisticdigital divide and were committed to supportdevelopment of software in local languages

• Affirmed their “commitment to providingequitable access to information and knowledgefor all, recognising the role of ICTs foreconomic growth and development”

Purpose of project

• Demonstrate the technology by creating realvoice service

• Wanted real and useful information –contacted the National Agriculture andLivestock Extension Programme (NALEP)

• Farming provide livelihood to 75% of theKenyan population

• Difficult to get information today as theAgricultural Extension Officers are few(~5,500 trying to reach 800,000)

Why a Banana Information Service?

• Complement to extension workers• Educational tool and reference system –

can confirm details• Why we started with bananas:

– Grown in many areas– Important crop in terms of income and food

security perspective

Sources of Information

• “Fruits and Vegetables TechnicalHandbook” from The Ministry ofAgriculture and Rural Development

• David O. Nyantika, NALEP• Prof. Esther M. Kahangi, JKUAT• Kenya Agricultural Commodity

Exchange, KACE

Festival and Festvox

• A general multi-lingual speech synthesissystem developed at Centre for SpeechTechnology Research (CSTR) at the Universityof Edinburgh(http://www.cstr.ed.ac.uk/projects/festival/)

• Free software written in C++ with a Scheme-based command interpreter for general control

• The Festvox project aims to make the buildingof new synthetic voices more systemic andbetter documented, making it possible foranyone to build a new voice.

GNU Bayonne

• A free telecommunications application server• Supports a wide range of computer telephony

interface hardware and voice over IPimplementations

• Designed to be an application developmentplatform that easily allows developers to scripttelephony applications and add support fornew hardware devices

XSL Transformations

• XSLT (Extensible Stylesheet LanguageTransformations) is an XML-based languageused for the transformation of XML documents

• The original document is not changed; rather,a new document is created based on thecontent of an existing one

• The new document may be serialized (output)by the processor in standard XML syntax or inanother format, such as HTML or plain text

Usability testing

• Testing with 10 farmers in Kibirigwi, Kirinyaga• Full compliance with

strict ethical guidelinesand industry standardsrelating to undertakingtests with humanparticipants

Tests

• The tests were compiled by Pernilla Näsforsand Yvonne Spittles, a PhD student at ThamesValley University, England, and conducted byPernilla Näsfors and Dr. Mucemi Gakuru.

• Each participant was given 3 sheets containingthe following:– a consent form giving their personal details– a task sheet with questions to answer from using the

system and– a user satisfaction questionnaire to give their

impressions of the system.

Participant Profile - GenderGender

M70%

F30%

70% of the participants were male

30% of the participants were female

Participant Profile - AgeAge

41+60%

31-4030%

18-3010%

60% of the participants were aged 41+

30% of the participants were aged between 31-40

10% of the participants were aged between 18-30

Telephone usageTelephone usage

Weekly50%Daily

30%

Rarer than weekly20%

30% of participants used a telephone daily

50% of participants used a telephone weekly

20% of participants used a telephone more rarely

Computer usageComputers usage

Often10%

A little10%

Never80%

80% of participants have never used a computer

10% of participants have only had little use of acomputer before

10% of participants used a computer often

Test Results - Ease of useEase of use of Banana Information

System

Yes90%

Not Sure10%

90% of participants stated that they found thesystem easy to use

10% of participants stated that they were not surewhether or not the system was easy to use

Ease of selecting options from menu

Clarity of Menu Options

Yes80%

Not Sure20%

80% of participants stated that they could easily tellwhich option to select from the menu

20% of participants stated that they were not surewhether they could easily tell which option to select

from the menu

Clarity of Speech

Yes70%

Not Sure30%

70% of participants stated that the speech from the systemwas very clear to understand

30% of the participants stated that they were not surewhether the speech from the system was very clear to

understand

Clarity of speech

Preference for gender of speechPreference for Speech in Same Gender

Yes70%

No30%

70% of participants indicated that they would prefer thespeech to be in the same gender as themselves

30% of participants indicated that they would not preferthe speech to be in the same gender as themselves

How usability is measured

• Usability is not one single element of a system butmoreover, is considered to be made up of five maincomponents which are integrated and can be classifiedas follows:– Learnability– Efficiency– Memorability– Errors– Satisfaction

• The tests undertaken on the Banana InformationSystem assessed the usability of all of the abovesections apart from memorability and efficiency whichcould not be measured in a single test.

Learnability

• The Learnability component of usability refers to how easy itis to use the system.

• Even though the participants had a low level of experience inusing Information and Communication Technology, 80% ofparticipants stated that they could easily tell which options toselect from the menu and 90% of the participants stated that,overall, they found the system easy to use.

• 10% of the participants had low levels of literacy skills but theresults suggest that this did not affect their ability to learn thissystem.

Satisfaction

• The Satisfaction component of usability refers to thepleasantness of use of the system and the likelihood ofusers being subjectively satisfied after using it.

• 100% of participants stated that they would use thissystem instead of using other resources such as booksor the Internet.

• This is interesting as 60% of the participants can becategorised as older users aged 41+ who, traditionally,have been found to be more resistant to change in ICTdevelopments.

• The Errors component of usability refers tothe accuracy of using the system. The systemshould have a low error rate (percentage ofwrong responses) and if errors are made theyshould be quickly recovered from.

• The mean average error rate of 36% washigher than expected and suggests that, as incommon practice with most usability tests,some elements of the interface may needmodifications to meet the needs of the endusers.

Errors

Difference between languages• All of the participants who listened to the

speech in Kiswahili stated that the speechfrom the system was very clear to understandbut of the participants who listened to thespeech in English, 43% stated that they werenot sure on the clarity of the speech.

• A research version of a Kenyan English voicewere played to the participants and they allsaid it sounded even clearer than the Kiswahilivoice. Further development of this voice is inprogress.

Other findings• 100% of participants stated that the system

would be useful for banana farmers. They alsoexpressed a wish to extend the system toother crops, and especially – to livestock.

• 90% of participants stated that if they had anissue about growing bananas, they wouldusually seek help from Agricultural ExtensionOfficers; 10% stated that they usually soughthelp from other farmers. They commentedthat there are not enough officers available.

Reactions from NALEP• The system would fill an information

gap and increase the interest forextension services

• The system was well received by 30extension officers

• British English accent not clear – needto use Kenyan English TTS

• Difficult Kiswahili grammar – need tomake translation informal

Reactions from KSB• The Kenya Society for the Blind (KSB)

acknowledged the need for voice-basedservices among people who are visuallyimpaired

• Their alternative is to have to rely onother people to provide information tothem

Future system:Other crops + livestock

• Easy to extend to other crops and tolivestock

• Support enterprise selection• Can have separate phone numbers for

different crops• Add information about e.g. value

addition

Future: Local information

• Local market information• Suitable crops to grow in a specific area• Contact information to the local

agricultural extension officers

Future: Up-to-date info

• Commodity prices and other marketinformation

• Weather• Urgent announcements

– Disease outbreaks, e.g. bird flu

Future: Personal information

• Enter acres of land and get calculations ofpossible revenue, required investments etc.

• Enter time of planting and get instructionssuitable for the stage your plants are in

• Can use caller-id and pin-code foridentification and keep database with all infoso it doesn’t have to be re-entered.

Future: Integration with SMS

• Can be given the option in thetelephone system to get keyinformation sent by SMS or e-mail

• Can subscribe to e.g. marketinformation

• Can get alerts via SMS of e.g. urgentannouncements, awaiting e-mails etc.

Future: Simple update of info

• Can create website where anyone easilycould update or enter new informationthat immediately becomes available inthe telephone system

• Updates can be done at e.g. district orprovincial level by extension workers

• Farmers could also add information orpost questions to the system

Drawback: Cost

• Premium rate service:Normal calling rate + ~5 KSh

• Can take 2-5 minutes from beginning of thecall to finishing listening to a section– Can shorten time by providing information on how to

access things quickly

• Cost of SMS vs. Speech– Time to read 160 characters is ~15 sec. which

translates to half the cost of the SMS

Ways of cutting costs

• Can provide landline phone atInformation Desks, or ”offline” versionof the service on a computer

• One call per Common Interest Group• Possible to convince mobile operators to

make service very cheap at morninghours?

• Get government and/or donors tosubsidise calling rates?

Other services

• SMS Further info• Value added Information Service

– E.g. Commodities, Weather, Health,E-government, Insurance, Banking

• TTS good for providing personal orsensitive information

Other languages

• Possible for a linguist together with anengineer to within 6-8 months produce a goodquality TTS system for a linguistically simplelanguage like Kiswahili

• Database at www.llsti.org with languagefeatures that add complexity when buildingTTS

• Can create limited-domain TTS before a fullTTS can be developed

Further testing and research

• Further tests on the interface of the system soit is comprehensible by its target users

• Some improvements of the Kiswahili isneeded, e.g. for enabling simultaneous TTS.

• As 70% of the users stated a preference for aspeaker of the same gender, futuredevelopments could include male and femaleoptions in both languages

Conclusion of tests - Strengths

The findings suggest that despite low levels ofexperience with Information and CommunicationsTechnology:

• a system has been developed which meets thesatisfaction of the target group;

• the system is easy to use and;• the target group would prefer to use this system instead

of some other resources that they already haveavailable.

Future development

• Extend to other crops and to livestock• Possible to get local, personal and up-

to-date information, as well asintegration with SMS and e-mail

• Easy input and updates – enablescommunity involvement

• Improvements of voices – Kiswahili andKenyan English

Successful ICT projects

• Affordable• Scalable• Self-sustaining• Sensible• Simple ICT components• Involvement of local community and

professional people

Access to information important

• The Kenyan government recognisesthat the effective use of information andknowledge is becoming the most criticalfactor for rapid economic growth andwealth creation, and for improvingpeople’s socio-economic standards andquality of life

Thank you!

Asante sana!

Tack så mycket!