2. 2
Outline
Introduction and Brief history.
IVR general using and applications.
IVR definition , deployment and Ivr-system .
IVR techniques :
I. DTMF IVR .
II. Speech recognition IVR.
IVR phonetic speech recognition model .
Speech recognition system engine .
Speech recognition IVR types .
Advantage and Disadvantage of IVR .
4. Introduction and Brief History
Introduction
When a customer calls in a company. Call is answered, not by
conventional receptionist , but by an electronic receptionist
(an automatic attendant).
This e-receptionist directs you towards getting your query
resolved. But , Who is this electronic receptionist? This
Electronic Receptionist is IVR ( Interactive Voice
Response )
And this what will talk about it in this presentation .
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5. Introduction and Brief History
Brief History
Between the 1961 and the early 1970s a big breakthrough in a speech
technology and telephone service are occurred when the American Bell
Telephone Company unveiled of a developed Telephone System with a
new tone dialing methodology that could dial area codes using DTMF
technology , and when a link between speech and mathematics is
appeared by Leonard E. Baum, and Lloyd R. Welch who developed
an approach to recognition based on a statistical concept called the
Hidden Markov Model. The blueprint for IVR was born as Voice
Response Systems are based on DSP technology with limited and
small vocabularies .
Early 1980s , Leon Ferber realized that hard drive technology has
finally reached a cost effective price point . this make the system could
store digitized speech on disk, play the appropriate spoken message,
and process the human's DTMF response.
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6. Brief History.
In the late 1990s , while the call centers began to switch to multimedia ,
companies started to utilize the computer telephony integration (CTI) to
create a vital IVR system which acts as agent which collected customer
data to enable intelligent routing decisions.
Recently , With improvements in technology, systems could use speaker-
independent voice recognition of a limited vocabulary instead of requiring
the person to use DTMF signaling.
_______________________________________________________________________
And below some examples and details about using the IVR in turkey
First IVR System / 1991
ITD (Information Technology Division) successfully implemented the first interactive
voice response systems in Turkey at Pamukbank*, Yapý Kredi Bank and Akbank.
First Digital IVR / 1992
ITD made the implementation of the first biggest digital IVR system in Turkey.
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7. Brief History.
First National Switch Center (BKM) / 1993
ITD has important contributions at the formation of the first and only transaction switching
system project of Turkey.
First Internet Integrated Call Center / 1998
ITD began to work on the first internet integrated call center project at Garanti Bank and
successfully made the implementation in February '99.
First Speech Recognition System / 2000
ITD launched Turkey’s First Speech-Enabled Call Automation System in July 2001 with
Global Menkul Deðerler.
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9. IVR general using.
IVRS are used in many aspects in life but the general using of it in
(telephone system & World Wide Web ) as shown in these points
below
I.It used to Front-End a call center operation , to identify caller needs and
execute it and sometimes after (Security detection task) by comparing the
information obtained from the caller such as (caller account , pre-
recorder information ) with Caller ID data.
II.It used with Automatic Call Distributor (ACD) to play announcements
and received the inputs of the customers request .
III.It used in Voice Email to ask the customer if he want remove , read ,
edit and hear the message .
IV.Accesses or stores information to and from the back-end host,
database or the Internet by using applications used for Web pages such
as VoiceXML , CCXML and SSML .
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10. IVR applications.
IVR finds its application across the industries in many ways. As shoe
below :
1.Auto Receptionist: it means serving the call of customers.
2.IVRS telephonic alerts: used to call the customers or employees or other
stakeholders to provide them with some useful information .
3.Customer Care Automation .
1.IVRS inventory control : used to maintained the customer information over
the telephone line .
2.IVRS reservations: the speech-enabled IVRS is convenient way to book
tickets or spaces.
nIVRS Campaigning: such as using it for Social Campaigning like polio
vaccinations .
nIVRS Status Information .
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12. IVR definition , deployment and system
IVR detention
It is a technology that allows a computer to interact with humans through the
use of (1)DTMF (tones input via keypad) Or (2)Voice , and enables the
customer to retrieve information from a database, enter information into a
database, or both , By following a series of simple interactions in the form of
a conversation called the " IVR dialogue " . Thus , it allows to the customer
to efficiently exchange information , reduces " Written Processing ", cost
and improve the customer experience.
IVR general deployment
We can find the IVRS as :
I. Equipment installed on the customer premises .
II. Equipment installed in the PSTN (public switched telephone network) .
III. Application service provider (ASP) / hosted IVR .
IV. Virtual Hosted IVR
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13. IVR definition , deployment and system
Interactive Voice Response System (IVRS)
the system which provides a self-service for customers by guiding and enabling
them access to the Automated departments such as (Automated bank) , get
Services such as (airline schedules or movies times ) and Information that
they need such as (account information). By using technologies that allow a
computer to automatically detects voice and touch tones and analysis it
then react to customer request by providing the answers for their queries
via pre-recorded messages or dynamically generated audio , thus cut down
customer service costs .
IVRS components :
I. audio equipment .
II. DTMF tone recognizer .
III. language modeling technology .
IV. IVR's software application .
V. database.
VI. a supporting infrastructure
VII. sometimes , a text to speech converter is also used.
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14. IVR definition , deployment and system
IVRS architecture block diagram
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15. IVR definition , deployment and system
Where the Modern IVR systems enable users to interact through a computer
system via two interfaces :
I.Interactive Voice Response System Interface (IVRS-I) .
II.Interactive Web-Based System Response interface ( IWR-I ).
IVRS example
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17. IVR Techniques
There are three techniques are used by IVR to interpret the customer's
response to prompts:-
I. DTMF decoding .
II. Speech recognition .
III. Sometimes using TTS(Text-To-Speech) to speak complex and dynamic
information such as E-mail , news reports or weather information .
I. DTMF decoding technique
IVR with " Dual-tone multi-frequency signaling" approach is a technology
that allows computer to detect DTMF (Dual-tone multi-frequency) keypad inputs
which are generated by customer and trying to meet his request according to
input.
(DTMF) is an international signaling standard for telephone digits. These signals
are used in touch-tone telephone call signaling as well as many other areas
such as (interactive control applications, telephone banking and pager systems).
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18. IVR Techniques
A DTMF signal consists of two superimposed sinusoidal waveforms whose
frequencies are chosen from a set of eight standardized frequencies.
Low group (Hz): 697, 770, 852, 941
High group (Hz): 1209, 1336, 1477, 1633
And these frequencies detect by detector part of early DTMF systems consisted
of analog implemented bandpass filter-banks, which were tuned to the eight
standard frequencies.
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19. IVR Techniques
using for only the Public payphones that accept credit cards use these
additional codes to send the information from the magnetic strip.
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DTMF keypad
- The DTMF telephone keypad is laid out
in a 4×4 matrix of push buttons in which
each row represents the low frequency
component and each column represents
the high frequency component of the
DTMF signal. Pressing a key sends a
combination of the row and column
frequencies.
- But in the recent years , a group of keys
for menu selection: A, B, C and D were
dropped from most phones , and still
20. IVR Techniques
Keypad tones
In the table below the example of the tones of DTMF keypad
So for dialing , we will press many digits and that will create the dialing tone which
be superposition of many Low and High frequencies , as show in the next slide:
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DTMF keypad frequencies (with sound clips(
Frequencies
groups 1209 Hz 1336 Hz 1477 Hz 1633 Hz
697 Hz 1 2 3 A
770 Hz 4 5 6 B
852 Hz 7 8 9 C
941 Hz * 0 # D
Dialing ToneDialing Tone
21. IVR Techniques
For example
the key 1 produces a superposition of the tone with 697(Hz) and the tone 1209(Hz).
Initial pushbutton designs employed levers, so that each button activated two
contacts. The tones are decoded by the switching center to determine the keys
pressed by the user.
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1209Hz on 697 Hz to make the 1 tone
22. IVR Techniques
II. Speech Recognition technique
It is a technology that allows to taking the commands and execute functions
using natural voice signal instead of pressing the numbers on telephone or
machine .
Where the words spoken by the customer are chopped into smaller pieces and
compared with the words that are already stored in the database, and execute
the command which is most similar to the one stored in the database.
This enables customers to avoid complex DTMF commands. Also, unlike touch-
tone IVR/IVRS, it does not restrict the input to ten digits or keys. So, it is
allowing customers to interact more naturally.
Until now speech based IVRS is able to except few discrete numbers and
alphabets, instead of free flowing voice. But, speech-enabled IVRS allows user
to speak normal sentence rather to take unusual pauses. Also, these systems
allow voice signals of all frequencies rather accepting only single or very few
frequencies, thus making it speaker independent.
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23. IVR Techniques
In phone system , This IVRS is proved to be a good substitute to the
“receptionist attending” the phone calls. You can handle multiple calls at a time
using this technology. Thus reducing the labor cost and providing better customer
service. This works best when combined with a touch tone IVRS system. It is best
suited for applications where directed responses are needed, like where you are
giving option to the caller to answer in either YES or NO, and where the inputs
are limited.
And to ensure high efficiency, these systems use Artificial Intelligence (AI). (AI)
takes care of (1)dialogues (2)grammar (3) responses, in order to understand the
customer's requirement. Also, wave editors are used to improve the quality of
voice.
The programming languages which used to develop speech recognition IVRS
are Voice XML & Speech Application Language Tags .
But what is the speech recognition and speech recognition system engine
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24. IVR Techniques
Speech Recognition (SR)
It is the ability of a machine or program to identify words and phrases in spoken
language and convert them to a machine-readable format , it also known as
"Automatic Speech Recognition (ASR)" .
Most IVR system uses one or more of four categories Speech Recognition
methodologies in the conversion process.
1.Template Matching .
2.Acoustic-Phonetic Recognition .
3.Hidden Markov Model .
4.Neural networks .
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25. IVR Techniques
1- Template Matching
Template matching is considered the oldest and least effective method. It is the
primary technology applied to speaker verification, (Moore, 1982).
It is a form of pattern recognition.
Each word or phrase in an application is stored as a template.
The user input is also arranged into templates at the word level and the best match
with a system template is found.
2- Acoustic-Phonetic Recognition
Acoustic-phonetic recognition is a function at the phoneme level.
Where It is an attractive approach to speech as it limits the number of
representations that must be stored.
It involves three steps,
I. Feature Extraction.
II. Segmentation and Labelling.
III. phoneme-Level recognition.
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26. IVR Techniques
3-Hidden Markov Model
The Hidden Markov Model (HMM) is a popular statistical tool for modelling a wide range
of time series data.
The basic principle here is to characterize words into probabilistic models wherein the
various phonemes which contribute to the word represent the states of the HMM while
the transition probabilities would be the probability of the next phoneme being uttered.
Where models for the words which are part of the vocabulary are created in the
training phase .
in the recognition phase when the user utters a word it is split up into phonemes as
done before and its HMM is created.
After the utterance of a particular phoneme, the most probable phoneme to follow is
found from the models which had been created by comparing it with the newly formed
model.
This chain from one phoneme to another continues and finally at some point we have
the most probable word out of the stored words which the user would have uttered .
thus recognition is brought about in a finite vocabulary system.
Stochastic processing using Hidden Markov Models is accurate, flexible, and capable
of being fully automated .
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27. IVR Techniques
4- Neural networks
it is type of an artificial neural network which is a computer program, which attempt to
emulate the biological functions of the Human brain for recognition the speech .
it assumes that the speech recognition systems could learn a knowledge the speech
automatically and comprehends the meaning then response as the human brain .
this system consists of a huge number od accurate processors that perform reliable
speech processing .
until now , it is not actually wide apply in the IVR system .
Recent , the most of Speech Recognition IVRS uses a " Phonetic Speech Recognition
model " based on Acoustic-Phonetic Recognition Idea.
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HMM diagram
The state above the dash line is
the hidden states .
The O is the observation
sequence.
A is the state transition
probability.
B is the observation matrix
probability (emission ).
28. IVR Techniques
- In Phonetic recognition systems,
spoken words is break down into
small fundamental sound units
called phonemes. When
compared to word-based
recognition systems, phonetic
recognizers enable increased
accuracy in understanding larger
vocabularies.Language modeling
technology is also used to
heighten accuracy by comparing
recognized sounds to a list of
usage rules or constraints to
determine the probability of one
sound following another .
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IVR Phonetic Speech Recognition model
29. IVR Techniques
- Speech solutions are now enabling the development of IVR applications that go
beyond rigid touch-tone interface models to exploit the flexibility offered by
natural language processing.
- To aid recognition and reduce complexity, an "n-best list" of the most likely word
or phrase matches to the spoken utterance and associated confidence scores
are then created and interpreted by the system.
- Natural language recognition and advanced user interfaces that conduct
interactive dialogues with users in order to complete transactions are driving
the creation of the most versatile and robust applications ever developed for the
IVR industry.
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30. IVR Techniques
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Speech Recognition System Engine
Speech Recognition is implemented in 5 types of systems :
I. Speaker dependent system - The voice recognition requires training before it
can be used, which requires you to read a series of words and phrases.
II. Speaker independent system - The voice recognition software recognizes
most users voices with no training.
III. Discrete speech recognition - The user must pause between each word so
that the speech recognition can identify each separate word.
IV. Continuous speech recognition - The voice recognition can understand a
normal rate of speaking.
V. Natural language - The speech recognition not only can understand the voice
but also return answers to questions or other queries that are being asked.
Based on these SR-system types , the IVRS gained its categories .
31. IVR Techniques
Speech Recognition IVRS types
There are three main varieties of speech recognition IVRS :-
I. Touch-tone model
in this IVR type the dialogues prompt the customer with one option. For example :
System Prompt: "For checking information, press 1.“
Caller Response: “1"
II. Directed dialogues model
it is based upon predefined “grammars”, where dialogues prompt the customer with
specific questions or options. For example
System Prompt: "Would you like checking account information or rate information?"
Caller Response: "Checking", or "checking account," or "rates."
I. natural language dialogues model
it is based on statistically trained language models in which employ open questions
with free-form responses. For example :
System Prompt: "What transaction would you like to perform?"
II.Caller Response: "Transfer $500 from checking to savings.“
All the above IVRS types based on speech recognition but with different levels of
sophisticated and expense as shown in the next slide 31
Audio Example
Audio Example
Program example
32. IVR Techniques
But what are the Difference Between Natural
Language and Directed Dialogue ?
1.In directed dialogue model , the caller is
directed through a series of yes/no or
structured type questions with extremely
limited acceptable responses.
2.So , the user has a negative experience
and the company using the IVR has an
unsatisfied customer who will likely need to
be transferred to a live agent, which results in
higher business costs.
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3. on the other hand, the natural language model does not only recognizes speech, but
also interprets it. This means it has a much wider range of comprehension, allowing
the user to speak more naturally.
Natural Language Processing (NLP) meaning
It is a field of ( computer science, artificial intelligence, and computational linguistics )
concerned with the interactions between computers and human (natural) languages and
involves natural language understanding which enabling computers to derive meaning from
human or natural language input , and sometimes involve natural language generation .
33. IVR Techniques
IVR system advantages
1. The biggest advantage of IVR is saving time and money by :
I. taking care most of frequent questions which are asked by customers .
II. Duration of the work , IVR can be available 24 hours a day to field questions and help
customers with simple tasks.
III. IVR able to decrease the average duration of the call with a live operator even the
half and that mean save a big amount of money .
1. An IVR system can make a small company look bigger.
2. It easier for businesses and organizations to use these automated phone services for
supporting a “Buying and Selling” tasks by using the Advertisings and Promotions .
IVR system disadvantages
The greatest disadvantage of IVR systems is that many people simply dislike
talking to machines. Older adults may have a hard time following telephone
menus and lengthy instructions. And younger callers get frustrated with the
slowness of multiple phone menus.
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34. The endThe endAt the endAt the end
I want to thank dr.I want to thank dr. Fethullah for your help and supportFethullah for your help and support
And sayAnd say
““ thank you to all attendees “thank you to all attendees “
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