Chapter 5 Methodology and Research Result
5.2 Research Result
5.2.1 Questionnaire Result Analysis
Before the description of the analyzed result, author listed the survey question and hypothesis as following table for better understanding, see table 7.
Table 7 Survey Question versus Hypothesis
Item Survey question Hypothesis
H1
What are the major concern when purchasing LED components, quality, delivery, price, service, or else?
In LED component purchasing decision, quality, delivery, price, service are the most important influential factors.
H2
Among the major concerns of purchasing decision, what would be the most important factor?
Among the important influential factors, quality is of the top importance sequence.
H3 What are the most concerned issue of LED quality?
In terms of LED quality, the most concerned issue is the reliability.
H4 Among the dominant factors, what are the common quality requirements?
In terms of quality requirement among the dominant factors, the brightness, color, voltage, and viewing angle are the common required criteria.
H5
Among the common quality requirement of dominant factors, what would be the most important one?
Among dominant factors, the brightness is buyer's most important concern.
H6 Will experienced LED buyer be more quality oriented than first time buyer?
The re-buy decision of LED components is even more quality oriented.
H7
Will the sequence of importance of influential factor changed by the different functional role of the organization?
R&D staff is more concern quality rather than price (H7-1), while relatively the staff in purchasing division is more concern on the price issue (H7-2).
H8 Will the sequence of importance change by the sales channel?
Relatively, distributor is more critical on the quality requirement than direct customer.
H9 Does the selection of LED type mainly depend on the application?
The selection of LED type is mainly depended on the application.
H10 Does the quality requirement vary based on the environment of location?
The quality requirement for outdoor
application is more crucial than for the indoor usage.
Source: This study.
H1: In LED component purchasing decision, quality, delivery, price, service are the most important influential factors.
Result: According to the result of questionnaires, the frequency distribution (Figure 3) shown most of the people agreed the Quality (96.97%), Price (87.88%), Delivery
(57.58%) and Service (43.94%) were the important influential factors when they made decision of LED component purchasing, while only 4 out of 66 people (about 6.06%) thought other factors, such as : supplier’s financial status, product range, exclusivity, also important.
Figure 3 Influential factors of LED component purchasing Source: This study.
The sample size was 66, bigger than 30 copies, so according to the Central limit theorem, it was assumed normal distribution. This survey was using Likert 5-scale, so the value > 3 would be accepted. The Mean of Quality was 4.8485, Price was 4.6061,
Delivery was 3.8030, and Service was 3.6563, all of them shown of importance. Author used the one sample T-test to verify based on the 95% confidence interval, P < 0.05. And
the result shown Quality, Price, Delivery, Service of great significant, the P value was 0 for all of 4 items, see Table 9, so the hypothesis H1 was accepted.
Table 8 Mean and Standard Deviation of H1
N Mean
Std.
Deviation Std. Error Mean
Quality 66 4.8485 0.43826 0.05395
Price 66 4.6061 0.55133 0.06786
Delivery 66 3.803 0.78876 0.09709
Service 64 3.6563 0.96311 0.12039
Others 15 3.6 1.54919 0.4
Quality 34.265 65 0 1.84848
Price 23.666 65 0 1.60606
Delivery 8.271 65 0 0.80303
Service 5.451 63 0 0.65625
Others 1.5 14 0.156 0.6
Source: This study.
H2: Among the important influential factors, quality is of the top importance sequence.
Result: Based on the above Frequency distribution of H1 (Figure 3), it shown the quality issue is the most important influential factor (96.97% ) of the LED component
purchasing decision. Author also do the T-test result based on the 95% confidence interval, P < 0.05, to compare Quality factor to Price, Delivery, Service and Others individually by the value of Mean, and all the results shown the significance (P value =0), see Table 10, 11, 12 and 13, so the hypothesis H2 was accepted.
Table10 Quality versus Price
Test Value = 4.6041
Table 11 Quality versus Delivery
Test Value = 3.8030
Table 12 Quality versus Service
Test Value = 3.6563
Table 13 Quality versus Others
Test Value = 3.6
T Value Degee of
Freedom P value Mean Difference
Quality 23.143 65 0 1.24848
Source: This study.
H3: In terms of LED quality, the most concerned issue is the reliability.
Result: In terms of LED quality, from the frequency distribution shown 58 out of 66 persons (around 88%), see Figure 4, agreed the reliability issue (Recessive factors) was the most important concern, while only about 12% of people think otherwise. And the recessive factors of LED quality was shown as follows for LED user’s reference.
Figure 4 Pro-Recessive factors Source: This study.
Figure 5 Recessive factors of LED quality Source: This study.
Author used binomial test (based on sign-test of non-population) to verify, if the value >0.5 then it would be accepted. The actual vale was 0.88, the test result was approved of great significance (see Table 14, P value =0), so the H3 is accepted.
Table 14 Binomial Test for Reliability (Recessive Factors)
N
Observed
value Test value P value relability
(Recessive Factors)
Group 1 (Pro) 58 0.88
0.5 .000(a) Group 2 (Con) 8 0.12
Total 66 1
(a) ---- Based on Z Approximation.
Source: This study.
H4: In terms of quality requirement, (among the dominant factors) the brightness, color, voltage, and viewing angle are the common required criteria, for all LED package types.
Result: The method is the same as the H1, from the Frequency distribution (Figure 6), we could tell the Brightness (63/66), Wavelength (51/66), Voltage(28/66), Viewing Angle(40/66), Beam Pattern (29/66) were very important criteria; this study also did the verification by one sample T-test (see Table 15 and Table 16), the result shown the P value were =0, Brightness, Wavelength, Voltage, Viewing Angle were of significance (Table 16), so the H4 was accepted.
Figure 6 Dominant factors of LED quality Source: This study.
Table15 Mean and Standard Deviation of H4
N Mean Std. Deviation Std. Error Mean
Brightness 66 4.8333 0.45007 0.0554
Wavelength 66 4.2121 0.96898 0.11927
Voltage 64 3.7031 0.92031 0.11504
View Angle 65 4.0615 0.8638 0.10714
Source: This study.
Table 16 T-test result of H4
Test Value = 3
T value
Degree of
Freedom P value Mean Difference
Brightness 33.093 65 0 1.83333
Wavelength 10.163 65 0 1.21212
Voltage 6.112 63 0 0.70313
View Angle 9.908 64 0 1.06154
source: This study.
H5: Among the dominant factors, the brightness is buyer’s most important concern.
Result: From the above Frequency distribution of H4 (Figure 6), the Brightness factor is 95.45% which presents the most importance, and this survey used T-test to do the verification, comparing the Mean of Brightness to Wavelength’s, Voltage’s, Viewing Angle’s, and Beam Pattern’s, to see if the Brightness factor with significance. And the result shown all of the P value is 0, see Table 17, 18, 19 and 20.), so H5 was accepted.
Table 17 Brightness versus Wavelength
Test Value = 4.2121
T value
Degree of
Freedom P value Mean Difference
Brightness 11.214 65 0 0.62123
Source: This study.
Table 18 Brightness versus Voltage
Test Value = 3.7031
T value
Degree of
Freedom P value Mean Difference
Brightness 20.401 65 0 1.13023
Source: This study.
Table 19 Brightness versus Viewing Angle
Test Value = 4.0615
T value
Degree of
Freedom P value Mean Difference
Brightness 13.932 65 0 0.77183
Source: This study.
Table 20 Brightness versus Beam Pattern
Test Value = 3.7031
T value
Degree of
Freedom P value Mean Difference
Brightness 20.401 65 0 1.13023
Source: This study.
H6: The re-buy decision of LED Components is even more quality oriented.
Result: Among the 66 samples, 63 persons had experience with LED components, 3 persons never used LEDs (see Figure 7); for verify this hypothesis, author classified these 63 respondents into two groups, purchased LED “ Once” as the first –time user, and the others as the “re-buy” purchaser (see Figure 8), then using the SPSS software by the method of
ANOVA to analyze if the Quality factor present significant difference between these two groups, the F value is 0.065, and the result ( P value is 0.799 which is more than 0.05) shown there was no significance (see Table 21), so the H6 was rejected.
Figure 7 Purchasing frequency of Respondents Source: This study.
Figure 8 First-time versus Re-buy Source: This study.
Table 21 ANOVA result of H6 (Quality --- First buy versus Rebuy)
Sum of Squares
Degree of Freedom
Mean
Square F value P value Between
Groups 0.013 1 0.013
0.065 0.799 Within
Groups 12.472 64 0.195
Total 12.485 65
Source: This study.
H7: R&D staff is more concern quality rather than price (H7-1), while relatively the staff in purchasing division is more concern on the price issue (H7-2).
Result: From the job junction break-down, in the sample distribution Table 6, shown there were R&D 30 persons, while purchaser was 7 persons. This hypothesis was evaluated in 2 parts: H7-1 for the R&D group, and H7-2 for the purchasing personnel. (1) H7-1: Author picked out the R&D group’s selection of Quality factor to compare with Price factor, using the paired T-test to verify, although from the ranking shown Quality was greater than Price (Table 22), we found from the result of paired T-test in Table 23, the value was not of statistic significance, therefore, the H7-1 was rejected;
Table 22 Sequence of Importance
R&D group Quality Price Delivery Service
Mean 4.8667 4.6000 4.0000 3.3667
Ranking 1 2 3 4
Source: This study.
Table 23 Paired T-test of R&D group (Quality versus Price)
Mean Std. Deviation T value
Degree of
Freedom P value Quality -
Price 0.26667 0.73968 1.975 29 0.058
Source: This study.
(2) H7-2: Regarding the purchaser group, from Table 24 it shown the importance
sequence was quality first, second was price, and delivery and service were both in the third place. This survey was used also the paired T-test to compare the Price factor to Quality, Delivery and Service, to see if there was of great difference. And the result (Table 25) shown, although Quality was more important, Quality compared with Price was not of statistical significance, while Price compared with Delivery and Service were of significance. It meant purchasing staffs regarded the Price factor was more important than the Delivery and Service factor, but the Quality and Price factor were both very important, so H7-2 was rejected.
Table 24 Sequence of Importance
Purchasing group Quality Price Delivery Service
Mean 5.0000 4.5714 3.7143 3.7143
Ranking 1 2 3 3
Source: This study.
Table 25 Paired T-test result of Purchaser group (Purchasing --- Price versus Quality, Delivery, Service)
Mean
0.42857 0.53452 2.121 6 0.078
Price-Delivery
0.85714 0.69007 3.286 6 0.017
Price-Service 0.85714 0.69007 3.286 6 0.017
Source: This study.
H8: Relatively, distributor is more critical on the quality requirement than direct customer.
Result: From the respondents’ company business type break-down (Table 6 sample distribution), it shown there were 39 manufacturers (59.09%), 16 ( 24.24%) of others (IC design company), and 11 (17%) were distributors; these companies were classified into two
groups: Direct customer (Manufacturer and Others), and Distributor, see Figure 9, and then using ANOVA to verify if the Quality factor was more important to Distributors than to the
direct customers. And the result (Table 26) shown of no significance, so the H8 was rejected.
Figure 9 Direct customer versus Distributor Source: This study.
Table 26 ANOVA test result of H8 (Quality --- Distributor versus Direct)
Sum of Squares
Degree of
Freedom Mean Square F value P value Between
Groups 0.303 1 0.303
1.592 0.212
Within Groups 12.182 64 0.19
Total 12.485 65
Source: This study.
H9: The selection of LED type is mainly depended on the application.
Result: There were 63 out of 66 persons (95.45%) agreed the selection of LED type should be depended on the application (Figure 10), author used the binomial test (sign-test of non population) to verify, as the observed value 0.95 was bigger than the set criteria of 0.5, the result (see Table 27) shown of great significance (P value=0), so the H9 was accepted.
Figure 10 Frequency distribution of H9 Source: This study.
Table 27 Binomial test result of H9
N
Observed
value Test value P value YES_item21 Group 1 63 0.95
0.5 .000(a)
Group 2 3 0.05
Total 66 1
(a) --- Based on Z Approximation.
Source: This study.
H10: The quality requirement of LED for outdoor application is more crucial than for the indoor usage.
Result: The same as H9, also 95.45% of respondents (63/66) agreed the quality requirement of LED for outdoor application was more crucial than for the indoor usage (please refer to Figure 11); author also applied the binomial test (sign-test of non-population) on this hypothesis, and the result (Table 28) approved it was of significance. So, H10 was accepted.
Figure 11 Frequency distribution of H10 Source: This study.
Table 28 Binomial Test result of H10
N
Observed
value Test value P value YES_item22 Group 1 63 0.95
0.5 .000(a)
Group 2 3 0.05
Total 66 1
(a) --- Based on Z Approximation.
Source: This study.