INSTRUMENT DEVELOPMENT, RELIABILITY AND VALIDITY TESTS

Transcription

1 41 CHAPTER 4 INSTRUMENT DEVELOPMENT, RELIABILITY AND VALIDITY TESTS 4.1 INSTRUMENT DEVELOPMENT The research instrument used in the study consists of nine constructs. Each construct consists of set of items developed on the basis of literature review and suitable constructs was conceptualised on the theoretical definitions of each constructs. The instrument was classified into four segments. The first segment factors construct and obstacles faced construct, segment three consists of four constructs viz., Production and Inventory Management, Total Quality Management, Total Organisational Buy-in and Lean Manufacturing Techniques. The fourth segment consists of three constructs viz., benefits achieved, company performance and competitive advantage. The constructs containing items were measured using scaling techniques. The instrument development process was divided into five stages 1) item generation; 2) construct development; 3) pilot study; 4) large-scale data collection and 5) instrument validation. Item generation was done using extensive review of literature. Suitable items were identified and considered for the study with modifications based on the suggestions given by industry experts and members of industry associations. Selected items were grouped and classified under various constructs. The pilot study was carried-out by collecting responses from managers working in production and operations function. Few modifications in the instruments were made as advised by them. The instrument was fine tuned and finalised for large-scale data collection. The data collection was done based on the

2 42 sampling method to the firms identified as per the sampling frame. The reliability validity tests were performed for the items. The tested data was used for data analysis, model measurements and to test the research hypotheses. 4.2 RELIABILITY AND VALIDITY TESTS After receiving the responses, the data was organised and processed for item purification, reliability and validity tests, and unidimentionality tests. Purification of items was done with the Corrected Item Total (CITC) value. Item reliability was tested using the measure of alpha. Unidimentionality test was performed using PLS path modeling. For item purification, Corrected Item to Total (CITC) values was calculated. Items with more than 0.30 CITC values are considered for the study. Some of the items with slightly less than 0.3 were included considering its importance for the study. Reliability of constructs refers to the accuracy with which the constructs repeatedly measure the same phenomenon without much variation. The alpha that takes a value between 0 and 1 was tested for item reliability. values above 0.60 are acceptable for exploratory studies (Nunnally, 1978). Unidimentionality of constructs are measured by Confirmatory Factor Analysis (CFA). Unidimentionality is a common trait exhibited by all the indicator variables of any given construct (McDonald 1981; Hattie 1985). A structural equation modelling in used to test the unidimentionality of constructs. The unidimentionality of the constructs were tested with Average Variance Extracted (AVE) values. The constructs with AVE values greater than 0.5, are said to have convergent validity or unidimentionality (Chin 1995; and Chin et al 2003). The item reliability and validity results of various construct given in this section were performed as mentioned above.

3 External Factors External Factors (EXTFACT) construct was represented by ten items. The item code and item name is shown in Table 4.1. The items summary for the construct EXFACT is given in Table 4.2. Table 4.1 External Factors Construct items and item code Item No. Item Depiction 1 EF_1 Entry of foreign companies 2 EF_2 Increase in raw material price 3 EF_3 To meet International quality standards 4 EF_4 Tough national and international competition 5 EF_5 Competitive pricing by other manufacturers 6 EF_6 Rapid Introduction of new products in the market 7 EF_7 Government initiatives and schemes 8 EF_8 The customer want the product fast 9 EF_9 The customers are always demanding for a low price 10 EF_10 Customers expectations are high and changing very often Table 4.2 External Factors Summary Item Statistics Item Means Mean Minimum Maximum Range Variance No. of Items Reliability analysis and item purification: Table 4.3 shows the results of reliability analysis arrived for each item in external factors construct. Item purification was not required as the CITC values for all the items were above Therefore no item was deleted. The alpha values for all the items were also above than the acceptable value of The overall alpha of the construct was 0.88

4 44 Table 4.3 Reliability test results External Factors construct Corrected Item-Total Squared Multiple 's if Item Deleted EF_ EF_ EF_ EF_ EF_ EF_ EF_ EF_ EF_ EF_ Obstacles Faced (OBSTFACED) Obstacle Faced construct was represented by eleven items. The item code and item name is shown in Table 4.4. The items summary for the construct OBSTFACED is given in Table 4.5. Table 4.4 Obstacles Faced Construct items and item code Item No. Item Depiction 1 OF_1 Company is not fully aware of lean tools and techniques 2 OF_2 Management is not interested in implementing Lean techniques 3 OF_3 No proper training is provided to employees 4 OF_4 Implemented but cannot continue due to high employee turnover 5 OF_5 There is no interest shown from employees side 6 OF_6 Employees are interested but not empowered 7 OF_7 Employees are not ready to change to new practices 8 OF_8 In some areas, employees slip back to the old method 9 OF_9 The investment requirement is high for implementation 10 OF_10 No consultant is available for guidance and implementation 11 OF_11 Did not know where to start

5 45 Table 4.5 Obstacles Faced Summary Item Statistics Mean Minimum Maximum Range Variance No. of Items Item Means Reliability analysis and item purification: Table 4.6 shows the results of reliability analysis arrived for each item in obstacle faced construct. CITC score for item OF_10, representing availability of consultant for guidance and implementation was less than Thus item OF_10 was dropped and CITC scores were calculated for the remaining items thus resulting in more than 0.30 and above. alpha values for all the items were more than which was well ahead of the acceptable value of The overall alpha of the construct was Table 4.6 Reliability test results Obstacles Faced construct Corrected Item-Total Squared Multiple 's if Item Deleted OF_ OF_ OF_ OF_ OF_ OF_ OF_ OF_ OF_ OF_ Production and Inventory Management Production and Inventory Management (PIM) construct was represented by eleven items. The item code and item name is shown in Table 4.7. The items summary for the construct PIM is given in Table 4.8.

6 46 Table 4.7 Production and Inventory Management Construct items and item code Item No. Item Depiction 1 PIM_1 We predict the customer demand and accordingly the production planning is done 2 PIM_2 We use the Pull production system and no waiting for material at every work station 3 PIM_3 The inventory Levels are high at all work stations 4 PIM_4 Our suppliers supply material only when it is needed 5 PIM_5 We use Kanban squares or containers in the shop floor 6 PIM_6 Supermarket concept is used for maintaining inventory buffers 7 PIM_7 Product quantity routing has to be improved in many areas 8 PIM_8 99 % the products are delivered on time 9 PIM_9 Finished goods are stocked in excess to meet out the demand 10 PIM_10 The frequency of purchase is improved in last two years 11 PIM_11 Visual Pull Signals are well used in process flow Table 4.8 Production and Inventory Management Summary Item Statistics Mean Minimum Maximum Range Variance No. of Items Item Means Reliability analysis and item purification: Table 4.9 shows the results of reliability analysis arrived for each item in production and inventory management construct. The initial CITC scores for two items PIM_4 and PIM_6 showed less than These items were dropped and final item purification for all other items were arrived. Though the CITC score for item PIM_3 was slightly less than 0.30 it was retained as this was considered important for the construct level analysis. The alpha for the construct was which is above than the acceptable value of 0.70

7 47 Table 4.9 Reliability test results Production and Inventory Management construct Corrected Item-Total Squared Multiple 's if Item Deleted PIM_ PIM_ PIM_ PIM_ PIM_ PIM_ PIM_ PIM_ PIM_ Total Quality Management Total Quality Management (TQM) construct was represented by eleven items. The item code and item name is shown in Table The items summary for the construct TQM is given in Table Table 4.10 Total Quality Management Construct items and item code Item No. Item Depiction 1 TQM_1 All critical processes are controlled using SPC Charts 2 TQM_2 Waiting time for materials at work stations are very high 3 TQM_3 Rejections are eliminated using fail-proofing method at critical points 4 TQM_4 Every place in the organization is neat and well arranged 5 TQM_5 The components produced by us meets the international standards 6 TQM_6 25 % of process improvement is achieved because of s 7 TQM_7 Department level meetings are held regularly to solve problems 8 TQM_8 Whenever a problem occurs, the root cause is identified and solved 9 TQM_9 Most of the products received from suppliers are delivered at point of use 10 TQM_10 We always compare our self with competitors 11 TQM_11 Communication (Top-down and Bottom-top) both ways need to be improved

8 48 Table 4.11 Total Quality Management Summary Item Statistics Mean Minimum Maximum Range Variance No. of Items Item Means Reliability analysis and item purification: Table 4.12 shows the results of reliability analysis arrived for each item in total quality management construct. One item TQM_11 was deleted during item purification and remaining ten items were included as the CITC values were above The alpha values for all the items were also above than the acceptable value of alpha for the construct was which is also above than the acceptable value. Table 4.12 Reliability test results Corrected Item-Total Total Quality Management construct Squared Multiple 's if Item Deleted TQM_ TQM_ TQM_ TQM_ TQM_ TQM_ TQM_ TQM_ TQM_ TQM_ Total Organization Buy-in Total Organization Buy-in (TOB) construct was represented by twelve items. The item code and item name is shown in Table The items summary for the construct TOB is given in Table 4.14.

9 49 Table 4.13 Total Organization Buy-in Construct items and item code Item No. Item Depiction 1 TOB_1 goals and targets 2 TOB_2 Best performer announcements are made regularly 3 TOB_3 Sign Boards are very effective and displayed at appropriate positions 4 TOB_4 Department problems are solved as a team exercise 5 TOB_5 Employees are rewarded whenever an improvement is made 6 TOB_6 At least 25 % of employees suggestions are implemented 7 TOB_7 There is lack of financial support for effective implementation of lean 8 TOB_8 Most of the suggestions will come from managers rather than operators 9 TOB_9 Most of the employees are not ready to change to a new method 10 TOB_10 Safety is a major problem in the departments 11 TOB_11 Employees are ready to stay back and work whenever need arises 12 TOB_12 Atleast 60% of the employees have attended training programmes Table 4.14 Total Organization Buy-in Summary Item Statistics Mean Minimum Maximum Range Variance No. of Items Item Means Reliability analysis and item purification: Table 4.15 shows the results of reliability analysis arrived for each item in total organisational buy-in construct. Here again two items were removed during item purification. Item TOB_7 and TOB_11 was dropped as both the items was less than The alpha values for remaining items were above

10 50 Table 4.15 Reliability test results Corrected Item- Total Squared Multiple Total Organization Buy-in construct 's if Item Deleted TOB_ TOB_ TOB_ TOB_ TOB_ TOB_ TOB_ TOB_ TOB_ TOB_ Lean Manufacturing Techniques (LMT) Lean Manufacturing Techniques (LMT) construct was represented by eighteen items. The item code and item name is shown in Table The items summary for the construct LMT is given in Table Table 4.16 Lean Manufacturing Techniques Construct items and item code Item No. Item Depiction 1 LMT_1 5S 2 LMT_2 QC Circles 3 LMT_3 Poke Yoke 4 LMT_4 Kaizen 5 LMT_5 Just-in-time 6 LMT_6 Line Balancing 7 LMT_7 Set-up Time Reduction 8 LMT_8 Group Technology 9 LMT_9 Visual Controls 10 LMT_10 Value Stream Mapping 11 LMT_11 Cellular Layout 12 LMT_12 Takt Time 13 LMT_13 Single Piece flow 14 LMT_14 Quick Change-overs 15 LMT_15 Total Productive Maintenance, TPM 16 LMT_16 Jidoka (Autonomation) 17 LMT_17 Standard Operating Procedure, SOP 18 LMT_18 Machine reliability

11 51 Table 4.17 Lean Manufacturing Techniques Summary Item Statistics Mean Minimum Maximum Range Variance No. of Items Item Means Reliability analysis and item purification: Table 4.18 shows the results of reliability analysis arrived for each item in lean manufacturing techniques construct. Item purification was not required as the CITC values for all the items were excellent and above Therefore no item was deleted. The alpha values for all the items were excellent with minimum value of Table 4.18 Reliability test results Lean Manufacturing Techniques Construct Corrected Item- Total 's if Item Deleted LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_ LMT_

12 Benefits Achieved Benefits Achieved (BENEACH) construct was represented by eleven items. The item code and item name is shown in Table The items summary for the construct BENEACH is given in Table Table 4.19 Benefits Achieved Construct items and item code Item No. Item Depiction 1 BA_1 Quality Improvement 2 BA_2 Rejection Rate 3 BA_3 Meeting Customer demand 4 BA_4 Reduction in Inventory Level 5 BA_5 Wastage Reduction 6 BA_6 Productivity Improvement 7 BA_7 Delivery Lead Time 8 BA_8 Machine Downtime 9 BA_9 Product Cost Reduction 10 BA_10 Lot size reduction 11 BA_11 Product Cycle Time reduction 12 BA_12 Process Flexibility 13 BA_13 Setup time reduction 14 BA_14 Supplier Lead time reduction 15 BA_15 Work Environment 16 BA_16 Communication Flow 17 BA_17 Employee Morale 18 BA_18 Customer Satisfaction Table 4.20 Benefits Achieved Summary Item Statistics Mean Minimum Maximum Range Variance No. of Items Item Means Reliability analysis and item purification: Table 4.21 shows the results of reliability analysis arrived for each item in benefits achieved construct. One item was deleted out of the eighteen items. Item code BA_2 was dropped since the CITC score was less than Further item purification resulted in sixteen items having CITC

13 53 scores above 0.30 except one item BA_1 with This item was retained as it was considered important for the study. Further purification was not required as the alpha values for all other items were above than the acceptable value of The overall construct alpha resulted in an excellent value of Table 4.21 Reliability test results Benefits Achieved Construct Corrected Item- Total 's if Item Deleted BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ BA_ Competitive Advantage Competitive Advantage (COMPADVAN) construct was represented by nine items. The item code and item name is shown in Table The items summary for the construct COMPADVAN is given in Table 4.23.

14 54 Table 4.22 Competitive Advantage Construct items and item code Item Depiction 1 CA_1 The products are sold at lowest price when compared to competitors 2 CA_2 Customers buy our products only because of high quality 3 CA_3 We have an excellent delivery performance record to satisfy our customers 4 CA_4 We are the only company to offer more number of variety products 5 CA_5 Our products are known for its excellent design 6 CA_6 Customers come to us because we can supply any volume of requirement 7 CA_7 We get orders because we only have the technology / machines 8 CA_8 Customers come to us only for new product development 9 CA_9 Our products are sold well because of the best service we provide Table 4.23 Competitive Advantage Summary Item Statistics Mean Minimum Maximum Range Variance No. of Items Item Means Reliability analysis and item purification: Table 4.24 shows the results of reliability analysis arrived for each item in competitive advantage construct. Item purification eliminated 2 items CA_1 and CA_9. The CITC values for the remaining items were above The alpha values for all the items were also above than the acceptable value with the minimum value of for item CA_7.

15 55 Table 4.24 Reliability test results Competitive Advantage construct Corrected Item-Total Squared Multiple 's if Item Deleted CA_ CA_ CA_ CA_ CA_ CA_ CA_ Company Performance Company Performance (COMPERF) construct was represented by twelve items. The item code an d item name is shown in Table The items summary for the construct COMPERF is given in Table Table 4.25 Company Performance Construct items and item code Item No. Item Depiction 1 CP_1 2 CP_2 No. of orders 3 CP_3 New Customers 4 CP_4 Production Cost 5 CP_5 Market Share 6 CP_6 No. of Products 7 CP_7 Sales Turnover 8 CP_8 No. of Employees 9 CP_9 Export Orders (if applicable) 10 CP_10 Asset Value 11 CP_11 Sales Return 12 CP_12 Cost Control

16 56 Table 4.26 Company Performance Summary Item Statistics Mean Minimum Maximum Range Variance No. of Items Item Means Reliability analysis and item purification: Table 4.27 shows the results of reliability analysis arrived for each item in company performance construct. The initial item purification removed 2 items. CP_4 and CP_12 were dropped and final item purification resulted in ten items. The CITC values for item CA_1 was just below 0.30 and included for analysis as it was considered important for the study. The alpha values for the remaining items were above the acceptable value of 0.70 except for three items which is just below. Table 4.27 Reliability test results Company Performance construct Corrected Item-Total Squared Multiple 's if Item Deleted CP_ CP_ CP_ CP_ CP_ CP_ CP_ CP_ CP_ CP_