Discrete Time Signal Processing Third Edition And The Use Of DMAIC Methodology For Business Growth

Overview of Discrete Time Signal Processing Third Edition

Describe about the Discrete Time Signal Processing Third Edition?

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The call center was trying to effective solutions to enhance their business growth through application of six sigma principles. However, the management used DMAIC (Define, measure, analyze, improvement and control) methodology to resolve their problems. According to Alâ€ÂAomar, (2012) use of DMAIC methodology can generate useful output when an existing process is going to be improved. In this case,   call center management   focused on modifying its current service delivery process through DMAIC methodology.

Albeanu et al., (2010) opined that define phase of DMAIC methodology is not only important for determining project objectives; it is also useful to identify project deliverables to client.  Before starting this six-sigma project, the management completed tasks related to identification of key drivers for higher customer satisfaction. Main tasks of define phase include- specifying the targets   by using a project charter, identifying deliverables of this project at different stages,   identification of resources required in this project and mapping the final process (Ismyrlis and Moschidis, 2013). Customers show less tendency of preferring one particular organization if competition is high ((Johannesson, 2011).While conducting market analysis before commencement of this project, management    realized   that   other organizations of ITES (Information Technology Enabled Services) are also providing services to customers at the same cost. It indicates that customers can choose one organization from many options. It is making customer retention process more difficult.

Findings of the market analysis indicate that the business growth of this company is average with respect to other organizations. Although customer satisfaction is one of the most influencing factors business growth, other factors  such as  operating costs and  delivery time of services also  impact on the growth significantly (Nave, 2015).Pre project data  analysis reflects that the best performing organizations in market spend less on each call. Analysis also reflects that cost to each call depends on the wait time for customers, number of call transfers to other staffs and time spent on a call to answer questions of customers. Primary goals of the current six-sigma project are decided on basis of these findings. These goals include reduction of average cost of calls by reducing wait time and number of call transfers.

The tasks in define phase are as follows:

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Project charter development

Analyzing customer requirements

Full process plan development

Project Information

Project Name

Business growth enhancement  for call-center

Chartered date

Sponsoring organization

1-800 We Answer

Project start date

 

Revision Number

n/a

Target Completion date

 

 

Team Sponsors

Project sponsor

Contact Number

Project Black Belt

Contact Number

Project Green Belt

Contact Number

 

 

Additional Team members

 

Name

 

Role

Contact

 

 

 

 

 

 

 

 

 

 

 

Principle Stakeholders

 

Name

 

Role

Contact

1-800 We answer

Main Client

1-212-868-1121

 

 

 

 

 

 

 

Principle objective of the project is increasing business growth for the call center. It will be achieved by finding solutions for reducing operational cost for a call.  The project also aims at finding solutions to reduce wait time, number of call transfers and service delivery time.

 

Project Goals: 

There are several organizations in ITES industry which offer customers with different services at lower cost. As several options are available in ITES market it is always difficult to retain existing customers. Findings of   market analysis reveal that profitability in ITES market does not depend only on customer satisfaction. Operating cost of an organization also impacts on the net revenue. Operating cost for the organization is   already higher than other organization in reducing continuously. As service delivery time is also higher than best-performing organizations, the company is facing difficulties to retain its existing customers. High delivery time is also restricting current call-center to    attracts   new customers. Operating cost and service quality requires to be increased   to acquire better position in market. It also indicates that the organization needs to increase their customer satisfaction level for enhancing profitability.

Process problem:

Scope of the project:

Scopes of the projects are as follows:

·         Conducting a detailed market analysis through benchmarking technique and indentifying the position of the organization by comparing its performance with other organizations in same field.

·         Getting information from existing customers on their view regarding satisfactory services. It can be conducted by arranging telephonic interviews among customers. COPIS (Supplier, input, process, output, and customers) can be developed to document detailed information on clients.

·         Identification of available resources which needs to be utilized in more effective way to attain goal of the project and finding solutions to optimize usefulness of existing resources.

·         Identification of new resources which can be required to enhance business performance.

 

 

Process importance:

As competition is high in ITES industry, ‘We-answer’ requires enhancing their profit to avoid any degradation in their current market position. As several organizations are providing IT services to customers, it is important to reduce operating cost for attaining competitive advantages. However, the organization also requires reducing their operating cost to increase profitability. Other organizations in the same industry successfully reduced their operating costs and thus earned higher profit. Current condition of this industry clearly reflects that We-answer needs to stop increase in operating cost immediately to avoid further degradation. It also indicates that the organization also requires reducing   cost to per call for earning more profit. However, for attaining long term business growth only reduction in operational costs is not sufficient. The organization also needs to increase its customer base while retaining existing clients. It reflects that the improvement in service quality is one of the important factors for business growth.

 

 

Authorized resources:

Project Sponsor-Call center   management

Management of the call-center is responsible for ensuring that their staffs are co-operating with six-sigma team. They are also responsible for providing all supports and resources to six-sigma team whenever required.

Stakeholder-Six sigma team

 Members  of this  team are  responsible for  ensuring that  the current project is successfully executed  and all deliverables f  this project are able  to bring high ROI(Return On Investment) for the company.

 

Project schedule:

ID

Task

Duration

1

Definition Phase

15 days

2

Data collection from  neutral source

4 days

3

Data analysis

2 days

4

Informing  call-center management  about the  findings

0.5 day

5

Conducting   telephonic interviews  among customers

3 days

6

Gathering  data collected from customers and  development of  COPIS table

1 day

7

Identification of available resources required in this project

0.5 day

8

Team  development

1 day

9

Consulting  with call-center management regarding budget

0.5 day

10

Deciding  schedule for project

1 day

11

Drafting and finalizing  charter for  project

0.5 day

12

Developing project plan

1 day

13

Process mapping

3 day

14

Identification of  gaps and finding solutions

1 day

15

Meeting  with  call center  management

1 day

16

Measure  phase

5 days

17

Collecting data

3 days

18

Analyzing data

2 days

19

Improvement Phase

10 days

20

Prioritizing issues

2 days

21

Developing  solutions

5 days

22

Reviewing solutions with management

1 day

23

Developing strategy implementation plan

2 days

24

Control phase

2 days

Morgan and Brenig-Jones (2012) opined that phases in DMAIC approach are dependent on each other and outputs of every phase are important as these are used in next phase also. Activities in the measurement phase will be conducted on basis of the output of obtained in definition phase (Antony and Kumar, 2012). The management applied benchmarking approach to find their position in market. Use of benchmarking approach enables an organization to compare their performance with others (Jardim, 2013). Average costs per calls for different organizations in the industry are listed below:

The Importance of DMAIC Methodology

Figure 1: Comparison between costs per calls of different call centers

According to Zhu, Mao and Li, (2013) use of benchmarking techniques not only enables an organization to locate them in market; it is also useful for identification of key drivers for business growth (Barone et al., 2014). In this phase A COPIS chart is also developed on basis of the telephonic interviews conducted among customers.

Customer

Output

Process

Inputs

Suppliers

Clients

System engaged

Automatic answering  of calls

(Automated process)

·         Telephone connection

·         Call switching infrastructure

Phone service  providers and IT staffs

Clients

Information  is

 collected  in

 system

Collecting  queries

(manual)

·         Staffs

·         Infrastructure  to manage call

 Management and IT staffs

Clients

Decision  regarding responses

Evaluating  queries and determining  whether it can be answered

(manual process)

·         Database

·         Trained staffs

IT Staffs and HR department

Clients

Providing  solution

·         Available solutions collected

·         Successful Delivery of  collected  solution

·         Database

IT staffs 

Clients

Transferring query  to higher level

Transferring calls  if it cannot be resolved  by lower staffs

(manual process)

·         Higher level staffs

HR team

Management  of call center

Recording customer details and  successful resolution

·         Record data   regarding call

·         Collecting feedback from customers

IT staffs and call center management

Table 1: COPIS chart for call center

As stated by Yu and Ueng, (2012) development of COPIS chart is not only useful to resources required for each process, but it also can be used to predict the problems encountered during execution of the process. COPIS chart analysis is useful for development of process map (Kosina, 2013).In this project a process map is developed during definition phase to identify the problems that may be encountered by a caller.

 

Figure 2: Process map for answering call in call center

Key findings:

Comparison on average costs per call for different call centers indicates that the cost for each call is higher than average performing organizations. Analysis of the process map developed in this phase indicates that a customer may need to wait if the answering process is engaged. Delay in service delivery may also occur if the solution is not available to lower level staff. Delay in query processing can reduce customer satisfaction. On other hand, if the customer does not get any solution from staffs, satisfaction level also decreases. On basis of process map   analysis it is evident that increase in service delivery time of the organization is affecting the customer satisfaction level thus reducing net profit of organization.

In measurement phase of six sigma project, key findings of previous phase are used to determine factors which are affecting business growth of the organization (Yamamoto, Abraham and Malatestinic, 2010).On basis of pervious findings, it is evident that increased cost per call and service delivery time is affecting the revenue. However,   the organization also needs to increase availability of solutions so that the   queries presented by customers can be resolved on the first call. According to Kubiak, (2012) ease of information access enhances business growth. In the measuring phase, at first the reasons behind degradation of key business performance parameters are identified (Besseris, 2011) .Six sigma team aims to find solution for the problems identified in definition phase. In this phase, the team also determines standard values of key parameters which will be useful for upgrading market position.  Tasks of this stage are listed as follows:

Identification of supporting factors and Data collection plan: Data collection is one of the important tasks of measurement and analysis phase (Cano et al., 2012). Voehl (2013) suggested as major business performance parameters are influenced by different factors, inappropriate determination of these supporting factors often generate erroneous result. In this task factors influencing key parameters will be identified.

Standardizing business performance measurement parameters and comparing collected data with standards: In this phase, collected data will be compared with standardized values to identify the root causes behind variation in business performance. Outputs of measurement process will be used to compare the current performance of business with standardized performance (de Mast and Lokkerbol, 2012). It is also effective for prioritizing the areas which require to be improved.

The Define Phase of DMAIC Methodology

The current phase deals with measurement of two important business performance parameters-customer satisfaction and call per cost. Determining accurate knowledge on customer satisfaction level is difficult as it is dependent on several other parameters also (Neves and Nakhai, 2011).Here factors influencing customer satisfaction and cost per call are determined.

Factors influencing customer satisfaction:

Figure 3: Factors influencing customer satisfaction in call center

Figure 3 describes the factors which are influencing customer satisfaction level of the call center. Taghizadegan (2013) stated that   service delivery time is one of the most important factors which impact on   customer satisfaction. However service delivery time   depends on performance of staffs and accessibility of resources. According to Nicoletti (2013) organizations which   emphasize more on regular training of staffs, get the benefit of increased business growth. On other hand, performance of an employee does not depend on quality of training provided by organization, experience in a particular task also influences the expertise in that field (Tan, 2015) .From the above figure, it is evident that in this particular call center, time required for each call depends on the delivery of service medium. Use of web-based services such as E-mails reduces time span for a call. As selection of service delivery medium depends on customers’ preferences, total time span can become uncontrollable in some cases.

Factors influencing call per cost:

Figure 4: Factors influencing call per cost

Although availability of skilled employees is essential to reduce operating cost, availability of resources is also equally important for the purpose (Stephen, 2015).If time to access  required resources increase, operating  cost also increases (Kumar and Naidu, 2011).Figure 4 reflects if recovery time of information from databases increase, cost of each call will also increase. However, the cost also depends on nature of call.

Data collection plan: The project team identified some areas of business activities for data collection. The team also decided process how data will be collected.

Parameters

Data collection plan and actions

Customer satisfaction level

·         Conducting  survey by telephonic interviews,

·         Recording customer feedback after  each query

·         Analyzing the survey records to track   current  trends in market

Cost per call

·         Recording the total time to answer a call

·         Cost to  find the solution

·         Cost   for calling back the customer

Time required for  providing solution

·         Total number of days  required to satisfy the customer  is the problem was  not resolved  on first call

Service delivery time

·         Time required to start a communication (It will be tracked automatically by existing  system)

Waiting time Of customers

·          Total time the customers required to  wait  if the system was  engaged (It will  also be tracked automatically)

Number of transfers

·         Total number of call transfer to higher  authority (tracked automatically)

 

Table 2: Data collection plan

 Table 2 shows a collection plan which will be used to gather data. Proper development of data collection plan increases chance of getting accurate information (Lertwattanapongchai and Swierczek, 2014).In this plan, data regarding customer satisfaction level is given the most prioritized. Gathering information on customer satisfaction level is useful for identifying drawbacks in current system and  it also helps an organization to develop its  future  business  strategies (Srinivasan et al., 2014).However,  the data regarding  customer feedback  can be collected by  conducting  industry survey (Maleyeff et al.,2012). Feedbacks of customers can also be collected through telephonic interviews (Mandelbaum, 2012). Apart from these, a customer can be requested to give feedback whenever the call center is providing service. Staffs of the cal center can be engaged for collecting feedbacks from customers and conducting telephonic interviews.

Cost per call is one of the most influencing factors for net revenue of a call center. According to (Snee, 2010) measures taken to reduce operating cost can be more effective if the market expansion strategies are difficult to be implemented. Organizations operating in highly competitive market often shows the tendency to control operating cost for increasing revenue instead of implementing new market development strategies (Reosekar and Pohekar, 2014) .Cost per call for the call center can be measured in three stages. The total cost of a call not only depends on total time required to answer it, but it is also dependent on process of   searching solution from databases. Cost for answering each call also depends on number of call transfers to higher authority. Apart from this, call center management needs to record details of each call and also requires updating database   after communicating with a client. All these processes increase total cost of each call. Sometimes, staffs of the organization fail to provide satisfactory answer to a client. In such cases, staffs call the client back and it affects operational cost of organization. The total cost required to answer a call will be calculated by system.

Tasks in the Define Phase

Customer satisfaction depends significantly on the time required to deliver a service (Shaffie and Shahbazi, 2012). In this project, measurement on total time required to satisfy a customer is important. If the query is not resolved on first call, then the total number of days will be counted to measure delay in response. In case of call centers, prompt answer to the first call increases loyalty of customers to a particular organization (Singh et al., 2010).  Tasks in measurement and analysis phase of this project also include measurement of wait time. If a call is transferred to higher level for several times, wait time increases and thus customers’ satisfaction level decreases significantly. So   the number of call transfers will also be recorded automatically by system to identify queries which are difficult to answer at this stage.

Once data on major performance parameters are collected, next tasks of measurement phase deal with deciding standards for performance parameters Firka, (2010). Data standardization is important to develop improvement actions (Mitreva et al., 2014). The current and standardized values of some parameters are listed below:

Performance criteria

Standardized parameters

Current position

Percentage of Satisfied customers  after a call

85%

70-75%

Cost  for  responding a call

$30

$40

Percentage of transferred call

5%

10%

Average Wait  time

 

5-6 minutes

Time  required for first response of a call

 

6-7 minutes

Table 3: Standardized performance parameters and current position

Table 3 shows data for standardized performance criteria and current position of this call center. Ramly (2012) suggested that, organizations should set targets for future business development on basis of analysis made on its strengths and weaknesses. However, tendency of management to take risks is important for rapid business growth (Ping Yi et al., 2012). The six sigma team also developed the target values for key performance parameters according to existing infrastructure of an organization (Morgan and Brenig-Jones, 2012). In case of performance standardization also, attaining customer satisfaction is given the most importance. Currently, services of the organization able to satisfy only 70-75% customers. Project team set target to increase number of satisfied customers up to 85%.

On basis of the tasks conducted in the second phase it is revealed that the current supporting cost for each call of this call center are much higher than expected cost. So the project tem immediately find solutions to reduce operating cost. Number of call transfers is also higher than the expected value. As it increases wait time for customers, loyalty of customers reduces with increase in number of call transfer.

According to Parast (2015) determining the effects of   internal and external factors on revenue is important in improvement phase, as these findings are mandatory for deciding control actions. This phase of the project deals with determining solutions for the problems addressed in previous phases (Gershon and Rajashekharaiah, 2013). In this phase, six-sigma team recorded key reasons for degradation in business growth of the call center and also evaluated their impact on business performance. Tasks which are conducted in improvement phase are as follows:

Prioritization of remedial measures: At this stage, impacts of all business issues are recorded and evaluated. Remedial measures for these issues are also developed at this stage. However, these strategies will be implemented   according to their priority. All business issues should be solved according to their priority for getting better result (Neves and Nakhai, 2011).

Market Analysis Findings

Developing plan for improvement strategy implementation: Tasks in improvement stage include remedial strategy development plan for the call center.

On basis of analysis made in previous stages, issues affecting call center performance are listed according to their priority.

Reducing support cost for each call: Support cost for this call center is higher than most of other organizations in market.  It indicates that the organization requires reducing support cost for increasing profit.

Reducing number of call transfer: Analysis of collected data shows that staffs have a tendency of transferring calls to higher level. It increases wait time, reduces customer satisfaction and also increases cost of each call. Staff training and increasing availability of information is required to solve this problem.

Reducing wait time: Often customers have to wait for a long time to get responses and it reduces chances of returning back to this call center. Main reasons for this problems are- less availability of staffs and improper scheduling of work.

Improvement strategies   are implemented in different stages according to their importance in business (Guo and Zhu, 2014). Implementation plan for these strategies are shown below.

Target

Strategies

Reducing  support  cost

·         Implementing web based  services

·         Training staffs to reduce call transfer and number of call backs

Reducing Number of  call transfer

·         Increasing availability of right information

·         Staff training

Reducing wait time

·         Increasing  number of staffs

·         Changing  work schedule

Table 4: Remedial strategy implementation plan

In Six sigma process control actions are taken for a period (Plenert, 2012).Control actions for modified processes are being taken continuously (Gygi et al., 2013). Data regarding customer satisfaction, support cost, and service delivery time are recorded regularly and data are compared with standard .Management   is taking actions to upgrade the database. The organization is hiring new employees. Trainings are arranged for existing employees.

Conclusion:

Outcomes of this project reflect that improvement strategies are effective to solve problems faced by the organization. Although the call center required strategies which will result immediate   effect on business growth, these steps can effectively increase business growth in future also.

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