A holistic framework of supplier selection and performance evaluation for an XYZ automobile company

A HOLISTIC FRAMEWORK OF SUPPLIER SELECTION & PERFORMANCE EVALUATION OF XYZ AUTOMOBILE MANUFACTURING COMPANY

Purchasing and Procurement

MAY 24, 2015

Table of Contents

Sl No. Title Page No

Executive Summary 2

1. Introduction 3

2. Need for Holistic Supplier Evaluation Framework 4

3. Supply Chain of XYZ Company 6

4. Phase-Wise Approach to Supplier Evaluation Process 9

4.1 Phase1 - Identifying Procurement Needs 10

4.2 Phase2 - Identification of Potential Suppliers 11

4.3 Phase3 - Selection of Suppliers for 1st Period Planning Horizon 12

4.3.1 Weighted Point System and Fuzzy Logic Decision Making system 14

4.4 Phase4 - Continuous Evaluation of Supplier Network 16

4.4.1 Continuous Evaluation of Selected Suppliers 16

4.4.2 Collaborative Evaluation - Self & Supplier Evaluating Us 17

4.5 Phase5- Periodic Re-evaluation of Suppliers (For Retaining or Changing) 19

5. Conclusion 20

6. References 21

1


Executive Summary

The main objective of this paper is to propose a holistic framework for supplier selection and

performance measurement for the procurement function of XYZ Company. For the literature

review we firstly look at the importance of performance measurement in supply chain

management especially in context with the purchasing function and the supplier network. The

factors that needs to be considered in a holistic supplier evaluation framework are discussed.

We also look into what firms are currently doing and then enlighten the finer aspects of

evaluation which are often overlooked or neglected that leads to lower performance levels.

The paper then briefly describes the case company considered, the kind of business, strategic

goals along with the overview of the supply chain. The current issues in the supplier network

and the deficiencies in the supplier selection and evaluation process of the firm are brought to

light. The CPO has asked us to develop a more holistic framework for supplier selection and

evaluation. For this our team formulates phase-wise methodological and holistic framework

that is more comprehensive and effective than the existing selection and evaluation process.

We start out with the identification and classification of the procurement needs based on the

Kraljic portfolio model. Then we use Carter 10'c for the identification process of the

supppiers. Considering our organizational goals and the complexity in supplier network it

terms of the number of suppliers as well as type of qualitative and quantitative factors we

propose the Analytic Hierarchy Process (AHP) together with the fuzzy logic method to arrive

at final ratings suppliers. Further we discuss the concept of continuous improvement though

constant evaluation and feedback among stakeholders. This involves a mechanism of the

supplier evaluating us in addition to self-evaluation process. Finally we arrive at the

concluding re-evaluation that could be conducted quarterly or yearly depending on the

situation for the scope of terminating or renewing contracts with our suppliers.

2


1. Introduction

“Measurement is the first step that leads to control and eventually to improvement.

If you can’t measure something, you can’t understand it.

If you can’t understand it, you can’t control it.

If you can’t control it, you can’t improve it” - H. James Harrington

&

"If you cannot measure it, you cannot manage it" - (Garvin 1993)

As pointed out by Harrington and (Garvin 1993), performance measurement is one of the

most crucial aspects of any kind of management and has become a competitive necessity for

globalized supply chains. For any supply chain the cost, quality (both at a services level and

the supplies), along with the responsiveness of your suppliers make a huge difference in the

overall performance of the company. The qualification, selection and evaluation of the

suppliers is one of the key tasks performed by the purchasing and procurement function in an

organization and the need for a robust and comprehensive mechanism has become

increasingly critical.

In this paper we establish a methodological framework for the holistic performance

evaluation of XYZ Company which is OEM in the automobile sector based in Chonburi,

Thailand. The company is currently facing scrutiny from the board who are not happy with

current state of affairs of the supplier network. The board feels that immediate changes need

to be made in supplier evaluation framework as our company continues to grow globally. It

has become imperative to adopt a holistic framework that integrates cross-enterprise

frameworks for supplier relationship management (SRM) or supplier performance

management (SPM) in order achieve higher "triple bottom-line" performance. The Chief

Procurement Officer has asked our team to come up with a holistic plan for supplier selection

and performance evaluation. We approach this task in methodological manner by separating

the core activities involved in the evaluation processes into five phases, starting by

identifying our core procurement needs. The various steps involved and their importance in

each phase is discussed. Finally we look into the continuous improvement and supplier

development before arriving at the decision of retaining and removal of suppliers.

3


2. Performance Measurement & the Need for Holistic Supplier Evaluation Framework

(Gunasekaran 2007) defines performance measurement as the means of quantifying "efficiency

and effectiveness" by a set of metrics. Each industry has its own set of "rules of the game"

and there are dimensions which are more critical and contribute more to success or failure of

the business. The important aspect is to identify the right metrics and the right criteria while

viewing it holistically. The supplier qualification, selection and evaluation is one of the most

critical tasks of the purchasing process and the metrics under performance evaluation carried

out needs to be carefully defined considering all relevant factors.

Figure1 - Commonly Tracked Metrics for a Manufacturing Firm, Source- (Gordon 2008)

As pointed out by (Gordon 2008) most companies (approx. 50-75 percent) have a framework

for measuring supplier performance. However the number of these companies that are

4


satisfied with their current approaches are quite few in number. The supplier evaluation

process is quite complicated and challenging. (Gordon 2008) says that the biggest challenge

is to come up with the "right metrics" and even if some firms are successful in doing this,

they don't necessarily translate to achieving desired results. Why? The answer to that is, most

metrics that are used by firms are based on a standard norm which are usually borrowed from

other firms involved in the same type of business. Figure1 illustrates some of the common

metrics used by a typical manufacturing firm. Some of these metrics lack the required

customization with relevance to the firm's particular business objective. Also the ERP

systems that are in place are usually bought "of the shelf" and are configured to read specific

type of information such as supplier quality, on time deliver, inventory levels etc which do

not really capture business processes and practice quality (Gordon 2008).

In addition most firms try to single out individual procurement functions for improvement

without looking at it holistically. As pointed out by (Latham 2015), while the savings made

by the purchasing department is an essential component of evaluation, it must relate to saving

made from the entire production process, from raw materials to services while considering

the business growth. If the firms is buying material at the same price when it produces $10

million revenue, as to when it started with an investment of $1 million then the purchasing

department may not be doing their job well enough. He argues that "buying cheaper" is not a

useful performance measure if you consider the true or overall costs arising due to lower raw

material quality or the below par services rendered. For example costs arising due to returns,

liability claims or increased transportation costs. Analysing all these parameters and

including them in the evaluation methods will give a more accurate view of the purchasing

performance.

While farming the performance evaluation framework it is also essential to that the

capabilities of the suppliers are carefully considered it should not just be based on a

competitive process. These capabilities must be judged in relation to the firms specific

requirements. Supplier relationships is another important area along with supplier

development processes which is often neglected by firms while forming the evaluation

metrics. Some aspects under the supplier relationship criteria could be the negotiating

capability of the firm with respect to pricing, discounts and other benefits as well as the

ability to empower suppliers to manage themselves against the shared performance metrics.

5


There are various other areas where the evaluation of the supplier relationship must be taken

into consideration such as with respect to design, planning, forecasting and how well the data

and ideas are shared both internally and externally that achieves overall objective of the

enterprise. Lastly but by no way the least, the evaluators often fail to evaluate themselves or

their performance level with respect to the supplier as well as their contribution to the overall

organizational performance. The evaluation framework must be part of the overall supply

management program and must be aligned to achieve the overall objectives of the firms

"mission and vision" statement.

3. Supply Chain of XYZ Company

In this section a general backdrop of the case company considered is discussed. Figure2

shows the typical supply chain of the case company considered. The company is an OEM in

the automobile sector and is headquartered in Chonburi, Thailand, 100kms south east of

Bangkok.

Figure2: XYZ Company's Supply Chain

Over the past decade Thailand has seen tremendous growth in production and exports of

automobiles and auto-parts. Our company's business revolves around the same strategic

objective and are concentrating on business from overseas markets. However we face stiff

completion from Japanese firms such as Toyota, Mitsubishi and Honda who were earlier

6


entrants into this market. Though our firm has achieved substantial market share in the pick-

up trucks and the "eco-friendly" small car segment, the firm is still lacking in terms quality

and responsiveness of service provided to our valued customers. On carrying out the root

cause analysis, major reason is attributed to the quality of our supplier network.

Due to government regulations as well as for reasons of cost benefits, most of the parts and

assemblies are sourced from local suppliers. The final assembly is done in the company

factory. The manufacturing processes follows a "lean and agile” principle that emphasis on

reduction of wasteful process while being robust with agile methods to deliver quality

products in a fast and effective manner. As part of this strategy, the use of a distributor

network is minimised especially for local and nearby regions where we directly provide the

finished product to the dealers and end customers. The logistics activities are handled by a

third party which uses sophisticated and far reaching transportation and distribution network

to deliver our vehicles within the region.

Figure3: KRA's for Performance Measurement Framework, Source - (Karjalainen 2012)

Our procurement team's main focus is to get the best out of our supplier in terms of quality

and responsiveness and hence the main metrics under which we evaluate our suppliers were

focused in these two areas as shown in green in figure3. However as mentioned earlier our

company's performance is under scrutiny especially with regard to the supplier evaluation

framework as well as the performance of purchasing and procurement function under main

7


categories of Time, Cost, Quality and Supplier Management. There is a lack of holistic

approach and our team has been given the task to develop an effective evaluation framework

to get the best out of our suppliers as well as our procurement team. For this we first need to

analyse our core procurement needs and decide "what" to measure. We then link it to "why"

we need to measure and focus on the key aspects that is currently missing in our evaluation

framework both in terms of the suppliers and ourselves, the procurement team. Then we

decide on "how" to measure by developing appropriate methods that suit our requirement.

The supplier management and evaluation cycle that we intend to implement is shown in

figure and the phase wise approach of implementing it is discussed next.

Figure 4 : Proposed Supplier Management and Evaluation Cycle of XYZ Company

8


4. Phase-Wise Approach to Supplier Evaluation Process

Figure 5 : Proposed Phase-Wise Performance Evaluation Framework, Source - (Keramydas 2012)

The figure 5 illustrates our suggested framework for the evaluation process. The first three

phases deals with initial assessment of the problem and framing the right criteria for selection

of the suppliers based on our firms objective. These phases are crucial as developing the right

performance metrics at the start will ensure a greater firmness in evaluation process and

minimize the risks of alteration or re-work by changing the requirement mid-way. The Phases

4 and 5 deals with the continuous improvement and supplier development process where

periodic re-evaluation of suppliers along with our firm is collectively analysed and evaluated.

The actually achieved results in phase 4 & 5 are compared to the set standards in Phase 1,2 &

3 that enables better decision making with regard to the necessary steps that need to be taken

for supplier development or for their removal.

9


4.1 Phase1 - Identifying Procurement Needs

The first phase is to identify the procurement needs after which the required procurement

strategy must be developed. The first part in this stage is to classify the procurement activity

based on the kind of supplies, whether its critical for production or not. Our "direct

procurement" involves acquiring raw materials that are needed for production. These supplies

directly affect the ability of the firm to manufacture the vehicle and any disruption can

severely affect the revenue. They are usually got from a pool of suppliers, ordered in larger

quantities with best possible cost, quality and reliability. The other type is the "indirect

procurement" which involves purchasing supplies for the day to day activities of the business

which have a lesser impact on the firms bottom-line but is important none the less for

effective operations. Once this is done we further classify supplies based on "portfolio

purchasing model" developed by (Kraljic 1983), shown in figure 6, where items are classified

based on the level of criticality. The strategic items are those items that are critical to

production process, impact profit greatly and has a high supply risk. These items require the

most attention from our purchasing team and the supplier of these items must be cautiously

selected.

Figure 6 - Classification Matrix for Identifying Procurement needs, Source - (Kraljic 1983)

10


Leverage items are those supplies that have an impact on profit but do not have a high supply

risk. For these items we use our full purchasing power in order to get the best costs and

quality. Then we have the bottle-neck items. These items do not impact profit directly but

create bottle-necks or situations where the firm have not many options. These are usually

products where we have to depend on one supplier. Lastly we have the non-critical items

which can be got by any supplier and have low impact on profit.

Once these procurement needs are identified make-or-buy decision can be made and other

sourcing strategies such VMI, strategic alliance with suppliers, umbrella agreements etc can

formulated. This phase is more crucial in terms of the performance of our procurement team

as any error in judgement made with the identification or classification of supplies would

have ramifications on the overall performance. We would have started on the wrong foot by

sourcing a critical supply to the wrong supplier.

4.2 Phase2 Identification of Potential Suppliers

In this phase we identify our potential suppliers based on our specific requirement and their

capabilities in terms of the competency levels. Like phase1, this phase too affects the

procurement team’s performance or KRA's (Key Result Area) as wrongly identifying

suppliers would severely impact the quality and responsiveness of our supply chain.

Firstly we look at the supplier company's financial report to get a picture of the company we

are going to deal with. This is important with respect to matching the suppliers with our long

term or short terms goals. We then formulate a checklist based on the 10c's of supplier

evaluation developed by (Carter 1995) for the initial screening process (figure 7). We conduct

brain-storming sessions for the thorough examination of suppliers and the supplier's supplier

(tier2 & tier3 suppliers) based on these parameters. In order, to select the best supplier

sometimes there may be a need to trade-off between these parameters based on the core

capabilities of the supplier and how they relate to meeting our requirement. As pointed out

by (Fuh-Hwa 2005) these trade-offs need to be made at every stage of the supply chain while

integrating the performance metrics for different suppliers.

In addition, many aspects that were not adequately captured before such as "Clean" or

"Culture and Relationships" have been included. "Clean" refers to adherence to

environmental and safety standards along with adherence to the law of the land. This is

11


important as we seen in the past many suppliers, though they were good in their core

competencies, they had to be removed mid-way due corruption or other legal factors. Equally

important is the "Culture & Relationships" category which may include past history in

negotiation (qualitative), legal cases against previous buyers (quantitative) or general work

atmosphere (culturally complex or different from ours etc) that would affect the performance

of the supplier network.

Figure 7 : Carter's 10C's Supplier Selection, Source - (Carter 1995)

12


4.3 Phase3 - Selection of Suppliers for 1st Period Planning Horizon

As pointed out by (Monczka 2011) there is no "one best way" for the selection and evaluation

of suppliers. Though the overall objective is to minimize risk and maximize value the

evaluation must be based on the right criteria that is line with firm’s objective. (Sagar 2012)

emphasises the importance of determining the right criteria for selecting the supplier in the

automobile sector during the 1st period of the planning horizon. This is a stage where the

annual, quarterly plans based on forecasts are being studied and formulated. Most of the

existing literature broadly classifies the methods used in the selection process based on the

“Quantitative" and "Qualitative" factors. The quantitative approaches includes both

optimization and non-optimization techniques. (Partovi 1989), (Narasimhan 1983) and

(Nydick 1992) illustrates how the Analytic Hierarchy Process (AHP) can be used to for the

supplier selection process because of its intrinsic capability to handle both the qualitative and

quantitative factors that conceptualizes the issues within the supplier selection process. In

addition (Gnanasekaran 2006) research has shown that the AHP improves the decision

making process and reduces time taken to select supplier. As illustrated in figure 8, it helps

the evaluation team to understand the problem with respect to main objective and

systematically evaluate performance under each relevant criteria and sub-criteria.

Figure 8: Analytic Hierarchy Process for Supplier Selection, Source- (Prusak 2013)

13


Further, it is carried out in a "level based" approach where both, the qualitative and

quantitative metrics are evaluated under each category and sub-category. For example under

the "delivery" category one of the sub category includes the "compliance with due date"

which is further classified into "percentage late delivery" and "delivery lead time". Figure 9

illustrates this but not all parameters that are captured under each category and sub-category

are shown.

Figure 9: AHP - Level Based Metrics for XYZ Company

Now once these parameter is evaluated and rated by the decision makers at various levels

there will be a degree of vagueness in their subjective perception and it needs to be integrated

with the general framework. For this we propose to use the fuzzy-hierarchy-multi criteria

decision making process or FHMCD that integrate the multiple weightages of the decision

makers into a single rank.

14


4.3.1 Weighted Point System and Fuzzy Logic Decision Making system

The weighted point system is typically designed for quantitative measurement where the

weight or score given by the decision maker for each category and sub-category is multiplied

by the performance score that is assigned and then totalled to arrive at final rating. But the

problem arises when qualitative criteria needs to be considered (Kahraman 2003). Hence we

propose to use is the fuzzy logic method. (Sreekumar 2009) shows how the fuzzy approach

can be used for supplier selection and evaluation where there exists qualitative factors and

multiple criteria with more than one decision maker. Figure 10 shows an example where

there are of four main categories (C1,C2,C3,C4), four suppliers (S1,S2,S3,S4) and three

decision makers (D1,D2,D3D4).

Figure 10 : Rating of Decision Makers & Formulae for FHMCD Process, Source - (Sreekumar 2009)

Once the evaluation is done by the decision makers under various criteria, the aggregate

weights of each criteria must be calculated as shown in the figure 9 (step4). Next the

aggregate fuzzy rating of the suppliers is arrived at using the formulae shown in figure 10

15


( below step4). The linguistic evaluation say using subjective variables such as P (poor), F

(Fair), M (Medium), G ( Good) and VG ( Very Good) by the decision maker can be

expressed as positive triangular fuzzy number which is then used to construct the fuzzy

decision matrix. This is then normalized based on the importance of each criteria. Next the

positive ideal solution (FPIS) and negative ideal solution (FNIS) is found. The vertex method

is applied to determine the distance between two. Finally the closeness co-efficient, which is

the relative closeness of FNIS to FIPS, for each supplier is calculated which is used to rank

the supplier based on the predefined decision rule. The fuzzy approach is especially useful

when there are multiple decision makers or where the ranking of one can be challenged by

another. As suggested by (Herrera 2000) it helps in easier resolutions of the conflicts arising

in the evaluation process.

4.4 Phase4 - Continuous Evaluation of Supplier Network (Buyer and Supplier)

One of the main categories depicted in figure 3 is the Supplier Management category has a lot

to do with the effort put by both parties in the continuous improvement process. Earlier the

two sub-categories that captured this were the flexibility and commitment ratio. But these

need to be further defined based on supplier development level through the continuous

process of evaluation.

4.4.1 Continuous Evaluation of Selected Suppliers

As pointed out by (Gordon 2008) supplier evaluation is not an event but a process. There

must be continuous evaluation of the supplier along with our purchasing function on the

defined parameters of time, cost, quality & supplier management. (Morris 2010) elucidates

the importance of a closed loop performance improvement model for continuous evaluation

of the supplier network as shown in figure 11. The steps discussed in phases1 to 3 are

repeated with the only difference being the supplier is "on board" and data collected is shared

and jointly analysed to determine the areas that are lacking. The new set of improvement

plans are jointly formulated. This way a continuous collaborative effort is made by both

stakeholders.

16


Figure 11 : Continuous Improvement Cycle of SPS, Source - (Beijer 2012)

4.4.2 Collaborative Evaluation - Self and Supplier Evaluating Us

Self-evaluation is as important as the supplier evaluation. How well we as firm or the

department are doing with respect to improving the performance of the supplier is critical to

efficiency of our supply chain. In addition the parameters on which we are going to judge

ourselves must be well communicated to the supplier. It is also imperative for the supplier to

evaluate us (procurement department and the organization as whole) and timely communicate

the result to us. This is often neglected by most firms but is critical to supplier management

parameter and needed for the continuous self-improvement process. Some of the metrics for

the self and supplier evaluating us must include on time payment, level of data sharing,

availability of the procurement team (face to face & virtual meeting held and their outcomes),

level of trust and comfort with the buyer, knowledge transfer which includes both from the

buyer as well supplier and training for specific requirements.

17


Earlier, supplier evaluation constituted of a periodic reviews using static information

typically by using a balanced scorecard after which a review is done and action plans are

made. However times have changed and the availability of advanced technology such as

RFID, smart tags, barcodes, EDI, TMS, WMS, ERP2, MRP2, e-procurement, cloud

computing etc. have enabled most of the qualitative or quantitative criteria to be evaluated on

a "any-time" "any-where" basis. This transparency and visibility available must be fully

utilized by our team as well as the supplier to track the performance of any criteria faster and

respond better. Both participant should jointly work together to sort out issues and formulate

corrective measures. Say for example the on-time delivery parameter is poor for one of the

suppliers. The supplier and us would jointly work on the issue and find out the root cause,

such as transportation delays, component availability, location etc. and see if any change in

processes within the manufacturer, procurement team, supplier or our third party could

eliminate the problem. Such a collaborative framework where both participants are actively

involved in the improvement process have a greater impact on the performance than many

other quantifiable criteria.

Figure 12: Level of Buyer - Supplier Relationship, Source - (White 2013)

18


According to (White 2013), collaboration is not just about having common data, EDI or bi-

directional communication, but it is to work together to achieve the mutually agreed goals

resulting in a "win-win" situation for both parties. This does not happen overnight, it takes

time to build these relationships over a continuous development cycle. As supported by

(Kannan 2006) and (Ellram 1990) these "softer" or qualitative aspects such supplier-buyer

relationship, the collaborative nature have increasingly become more important than

traditional approaches of measuring the quantitative aspects. This also has an in direct impact

on other parameters of the buyer evaluation. For example the relationships could be leveraged

to get useful market information, meeting emergency order or in other words the supplier

meets "beyond the expectations". Figure 12 shows the various levels of the supplier

relationship which according to us must be included as part of the evaluation process.

4.5 Phase5 - Periodic Re-evaluation of Suppliers for the scope of Retaining or Changing

Based on the output of the phase 4 the suppliers would undergo one primary re-evaluation for

the decision of retaining or changing any of the suppliers. This would be either done quarterly

or half yearly basis based on the nature of the event that causes the change or criticality of the

need. The output or actual performance levels is compared with the set specific targets, and if

they are found to be satisfactory then we continue to monitor them as discussed in phase4. In

case a supplier is not meeting the pre-defined requirement or specific goals they must be

rejected. However it important to compare the performance of these suppliers with the new

potential suppliers, competing to take this spot. So we pool them along with the new potential

supplier and repeat the steps discussed in Phase2 & 3. In case these lower performing

suppliers cannot compete or fail in the new selection process they would be phased out (as

shown earlier in figure 4) along with the reasons and blacklisted from all sites so they do not

come up again in our search engine.

19


5. Conclusion

Performance evaluation is one of the most important aspects in managing and controlling the

supplier network. As we have seen in this case it is a complicated task to have a holistic

framework for an automobile supply chain considering the myriad of suppliers and variety of

parameters that need to be considered. There are various approaches and models that can be

used to tackle this challenge but the framework selected used must be based on what fits best

to the firms strategic objective or the "mission and vision" and by considering the nature or

the complexity in the network and type of qualitative or quantitative factors involved. Each

method researched had its own unique advantages and shortcoming. Our team felt the AHP

coupled with fuzzy logic method would suit best to the "multi-criteria" and "multi-decision

makers" involved in our supply chain and propose this approach to the CPO for the selection

and evaluation of the suppliers. However we still believe in the future, few more additional

aspects need to be considered and further optimization of the model would be required.

20


6. References

Beijer, A.,T.,. Design of a Supplier Performance Measurement & Evaluation System for DSM’s Petrochemical & Energy Group. Research Project, Twente University, 2012.

Carter, R.,. "The Seven C's of Supplier Evaluation." The Journal of Purchasing and Supply Management, 1995: pp.44-46.

Ellram, M.,Lisa. "The Supplier Selection Decision in Strategic Partnerships ." Journal of Purchasing & Materials Management, 1990.

Fuh-Hwa, Liu.,Hai,Fraknklin.,Lin,Hui.,. "The voting analytic hierarchy process method for selecting supplier." International Journal of Production Economics,Vol.97, 2005: pp.308-317.

Garvin, A.,D.,. "Building a learning organization." Harvard Business Review,Vol.71(4), 1993: pp.78-81.

Gnanasekaran, Sasikumar.,Velappan,Selladurai.,Manimaran,P.,. "Application of Analytical Hierarchy Process in Supplier Selection: An Automobile Industry Case study." South Asian Journal of Management,Vol.13(4), 2006: pp.89-100.

Gordon, R.,Sherry. Suppllier Evaluation and Performance Excellance - A guide to meaningful metrics and successful results. J.Ross, 2008.

Gunasekaran, A.,Kobu,B.,. "Performance measures and metrics in logistics and supply chain management: A review of recent literature (1995–2004) for research and applications." International Journal of Production Research,Vol.45(2), 2007: pp.2819-2840.

Herrera, F.,Herrera-Viedma,E.,. "Linguistic decision analysis: Steps for solving decision problems under linguistic information." Fuzzy Sets and Systems, 2000: pp.67-82.

Kahraman, C.,Cebeci,U.,Ulukan,Z.,. "Multi-criteria supplier selection using fuzzy AHP,Vol.16." Logistics Information Management, 2003: pp.382-394.

Kannan, R.,Vijay.,Tan,Choon.,Keah. "Supplier Selection and Assessment: Their Impact on Business Performance." Journal of Supply Chain Management,Vol.38(3), 2006: pp.11-21.

Karjalainen, Mikko.,. "Framework for Supplier Performance Measurement System." Master's Thesis, 2012.

Keramydas, Ch.,Xanthopoulos,A.,Aidonis,D.,. "A Decision-Making Framework for the Optimal Selection of Suppliers." 1st Olympus International Conference on Supply Chains. KATERINI,GREECE, 2012.

Kraljic, Peter. "Purchasing Must Become Supply Management." Harvard Business Review, 1983.

21


Latham, Andrew.,. Houston Chronicles-Small Business-Improved Methods for Evaluation of Purchasing Performance. 2015. http://smallbusiness.chron.com/improved-methods-evaluation-purchasing-performance-12248.html.

Monczka, M.,Robert.,Handfield,B.,Robert.,Giunipero,C.,Larry.,Patterson,L.,Patterson,. Purchasing and Supply Chain Mangement,4th Edition. Cengage Learning, 2011.

Morris, Wayne.,. How to Leverage Supplier Performance Management for Continuous Supply Chain Improvement . 6 30, 2010. http://www.sdcexec.com/article/10269181/how-to-leverage-supplier-performance-management-for-continuous-supply-chain-improvement.

Narasimhan, R.,. "An analytic approach to supplier selection." Journal of Purchasing and Supply Management,Vol.1, 1983: pp.27-32.

Nydick, R.,L.,Hill,R.,P. "Using the Analytic Hierarchy Process to structure the supplier selection procedure." International Journal of Purchasing and Materials Management Vol.28 (2), 1992: pp.31-36.

Partovi, F.,J.,B.,Banerjee,A.,. "Application of analytic hierarchy process in operations management." International Journal of Operations & Production Management,Vol.10, 1989: pp.5-19.

Prusak, A.,Stefanów,P.,Niewczas,M.,Sikora,T.,. "Application of the AHP in the evaluation and selection of suppliers." 57th EOQ Congress : Quality Renaissance - Co-creating a Viable Future. Tallinn,Estonia, 2013. pp.1-9.

Sagar, Kumar.,Manish.,Singh,Deepali.,. "Supplier Selection Criteria: Study of Automobile Sector in India." International Journal of Engineering Research and Development,Vol.4(4), 2012: pp.34-39.

Sreekumar, Mahapatra.,S.,S.,. "A fuzzy multi-criteria decision making approach for supplier selection in supply chain management." African Journal of Business Management,Vol.3(4), 2009: pp.168-177.

White, Andrew.,. "Best Practices Collaborative Advanced Planning & Scheduling presentation." Gartner,Inc.,, 2013.

22
