Efficiency analysis of edible canna farms in Bac Kan Province, Vietnam

國立屏東科技大學熱帶農業暨國際合作系

Department of Tropical Agriculture and International Cooperation

National Pingtung University of Science and Technology

博士學位論文

Ph.D. Dissertation

越南北干省食用美人蕉農場效率分析之研究

Efficiency analysis of edible canna farms in Backan Province, Vietnam

指導教授 Advisor: 彭克仲 博士 (Ke-Chung Peng, Ph.D.)

研究生 Student: 武氏姮 (Vu Thi Hien)

中華民國 109 年 7 月 10 日

July 10, 2020

I

摘要

學號：P10522021

論文題目：越南北干省食用美人蕉農場效率分析之研究

總頁數：142 頁

學校名稱：國立屏東科技大學 系（所）別：熱帶農業暨國際合作系

畢業時間及摘要別：108 學年度第 2 學期博士學位論文摘要

研究生：武氏姮 指導教授：彭克仲 博士

論文摘要內容：

在越南食用美人蕉被視為是重要的糧食作物，且創造收入並減少貧

困率，但近年來北干省食用美人蕉的生產面臨許多挑戰，如新鮮塊莖產

量不穩定，產品質量低劣，產品價格不穩定等，故提高食用美人蕉生產

效率將有助於越南北部山區的農民增加收入並維持其生計。不過，在越

南關於衡量農業效率的研究非常有限，其中至今尚無分析越南食用美人

蕉之生產效率相關研究。因此，本研究目的是使用資料包絡分析（DEA

）和隨機邊界分析（SFA）來評估北干省食用美人蕉農場之生產效率。

研究結果顯示，三波縣農場的效率（技術、規模、分配與經濟效率）高

於納里縣，表示納里縣的食用美人蕉農場可以透過採用合適的技術和有

效地利用投入來提高效率。其中，有 92.38%的納里縣農場和 83.06%的三

波縣農場經營處於規模報酬遞增階段，表示北干省的農場可以透過擴大

規模以降低生產成本，從而提高種植效率。另，食用美人蕉農場的平均

環境效率較低，納里縣與三波縣分別為 0.57 與 0.58，表示納里縣與三

波縣的農場在不改變當前產出和投入水準下，能分別減少 43%和 42%不良

投入量的使用。本研究還發現，納里縣農場比三波縣農場具有更高的能

源指標（能源比、能源生產率、淨能源），代表納里縣農場可以減少能

源投入，並略高於三波縣（分別為 54.54%與 53.61%）。另，食用美人蕉

II

農場的技術、經濟和環境效率受到教育和農業推廣接觸等相關因素的影

響。因此，本研究建議農業政策應著重於發展北干省的推廣體系，為農

民提供培訓與技術轉讓，以幫助農民提高在食用美人蕉的生產效率。

關鍵字：技術效率、資料包絡分析、隨機邊界分析、食用美人蕉農場、

越南

III

Abstract

Student ID: P10522021

Title of Dissertation: Efficiency analysis of edible canna farms in Backan

Province, Vietnam

Total Pages: 142 Pages

Name of Institution: Department of Tropical Agricultural and International

Cooperation, National Pingtung University of Science

and Technology

Graduate Date: July 10,2020 Degree Conferred: Doctoral Degree

Name of Student: Vu Thi Hien Advisor: Ke-Chung Peng, Ph.D.

The content of abstract in this dissertation:

Edible canna is considered an important food crop that can contribute to

create income and reduce the poverty rate in Vietnam. In fact, the edible canna

production in Backan province is recently facing many challenges such as

unstable fresh tuber yield, low-quality products, unstable of output price, etc.

Thus, improving the efficiency of edible canna production helps farmers in the

Northern mountainous regions of Vietnam increase income and guarantee their

livelihood sustainably. However, the research on measuring efficiency in

agriculture is very limited in Vietnam. It is the reason why, to date, there is no

study which is related to analyzing the efficiency of edible canna production in

Vietnam. Therefore, the aims of this study were to evaluate the efficiency of

edible canna farms in Backan province using data envelopment analaysis

(DEA) and stochastic frontier analysis (SFA) approaches. The findings

indicated that the efficiency (technical, scale, allocative and economic) of farms

in Babe district found to be higher than in Nari district, implying that edible

canna farms in Nari district can improve their efficiency scores by adopting the

IV

suitable technology and using inputs efficiently. In addition, 92.38% of total

farms in Nari district and 83.06% of total farms in Babe district were being

operated under increasing returns to scale, indicating that farms in Backan

province could improve their efficiency in edible canna cultivation by

increasing their scale to reduce the cost in production. The results also showed

that the average environmental efficiency of edible canna farms was low, of

0.57 and 0.58 for Nari and Babe districts, respectively, indicating that farms in

Nari district and Babe district could have the potential to reduce 43% and 42%,

respectively, of bad inputs usage without changing the current output and

conventional input level. Moreover, findings indicated that edible canna farms

in Nari district had high energy indicators (energy ratio, energy productivity,

net energy) as compared to other farms in Babe district, implying that farms in

Nari district had opportunities to reduce energy input with slightly higher than

that in Babe district (54.54% and 53.61%, respectively). The results of this

study also revealed that the technical, economic and environmental efficiency

of edible canna farms were affected by factors related to education and

extension contact. Therefore, this study suggested that agricultural policies

should focus on developing the extension system in Backan province to provide

training and facilitate technology transfer for farmers which can help farmers

to improve their efficiency scores in edible canna production.

Keywords: technical efficiency, data envelopment analysis, stochastic frontier

analysis, edible canna farm, Vietnam

V

Acknowledgements

My study was conducted in the Department of Tropical Agriculture and

International Cooperation (DTAIC), National Pingtung University of Science

and Technology (NPUST) during the period from 2017 to 2020. During this

period, I would like to express my appreciation and sincere thanks to my

supervisor, Dr. Ke-Chung Peng, for all his support and invaluable guidance on

my research. His intellectual instruction with meaningful suggestions and

comments help me to find the right method to complete my Ph.D. research

program on time. I also would like to express my sincere thanks to Dr. Rebecca

H. Chung for her assistance and kindness to revise and give valuable

suggestions for my papers.

I would like to express my appreciation and thanks to advisory committee

members: Dr.Feng-Jui Lin, Dr. Chien-Feng Tai, Dr. Biing-Wen Huang, and Dr.

Meng-Long Shih for their meaningful suggestions and comments for the

successful accomplishment of my research work.

I am grateful to Vietnamese and Taiwan government for financial support

for my Ph.D study program in Taiwan. I would also like to express my thanks

to the staffs of NPUST and DTAIC for their invaluable assistance for me to

complete my doctoral program. I would like to thank Thainguyen University of

Agriculture and Forestry for supporting and encouragements during the period

of my study in Taiwan.

I would like to express sincere thanks to Dr. Ha Quang Trung, the head of

Department of Economics and Rural development, Thainguyen University of

Agriculture and Forestry, for his kind and meaningful suggestions and

encouragement during the conduction of the survey and collection data in

Vietnam. I also would like to thanks to the staffs, all edible canna farms of both

districts, Nari and Babe, in Backan province for their great assistance in

VI

providing secondary data and information about edible canna production for

my research.

Finally, I am extremely grateful to my parents and my husband who

encouraged and supported me throughout my study period in Taiwan.

Especially, I am grateful to my daughter who motivated me to successfully

complete my research program. Many thanks to my relatives, colleagues,

students, and Vietnamese friends in NPUST for their encouragement, helps

during the time for studying and living in Taiwan.

VII

Table of Contents

摘要.....................................................................................................................................I

Acknowledgements........................................................................................................V

Table of Contents........................................................................................................VII

List of Tables................................................................................................................ XI

List of Figures............................................................................................................ XIV

List of Abbreviation....................................................................................................XV

Chapter 1 Introduction..................................................................................................1

1.1. Research Background................................................................................................1

1.2. State of the Problem...................................................................................................2

1.3. Objectives of the Study..............................................................................................3

1.4. Research Questions....................................................................................................4

1.5. Contribution of the Study..........................................................................................5

1.6. Structure of the Study ................................................................................................5

Chapter 2 Literature Review........................................................................................8

2.1. Scientific Characteristics of Edible Canna ...............................................................8

2.1.1. Origin and Distribution of Edible Canna..........................................................8

2.1.2. Scientific Classification of Edible Canna .........................................................8

2.1.3. Some Characteristics of Edible Canna..............................................................9

VIII

2.1.4. The Nutritional Value and Pharmaceutical Activities of Edible Canna.......11

2.1.5. Economic Benefits of Edible Canna...............................................................12

2.1.6. Summary of Studies about Edible Canna.......................................................13

2.1.7. Edible Canna Production in Backan Province ............................................14

2.2. Efficiency Measurement Concept and Efficiency Analysis Methods..................16

2.2.1. Efficiency Measurement Concept...................................................................16

2.2.2. Efficiency Analysis Methods...........................................................................18

2.2.2.1. Data Envelopment Analysis (DEA).............................................................18

2.2.2.2. Applications of the DEA in Agricultural Studies........................................18

2.2.2.3. Stochastic Frontier Analysis.........................................................................27

2.2.2.4. Applications of SFA Approach in Measuring the Efficiency of

Agricultural Production..............................................................................................27

Chapter 3 Research Methodology..............................................................................32

3.1. Study area .................................................................................................................32

3.1.1. Natural Conditions of Study area ....................................................................32

3.1.2. Socio - economic Conditions of Backan Province.........................................33

3.2. Sampling methods and Data collection..................................................................34

3.2.1. Sampling Design ..............................................................................................34

3.2.2. Data Collection...............................................................................................36

3.3. Theoretical and Data Analysis Framework............................................................37

IX

3.3.1. Study I: Analyze the Efficiency of Edible Canna Production Farms using

Two-stage Data Envelopment Analysis Approach ...............................................37

3.3.2. Study II: Evaluation of Environmental and Technical Efficiency of

Edible Canna Farms using SFA Approach ............................................................41

3.3.3. Study III: Evaluation of Energy Efficiency of Edible Canna Farms using

DEA Approach ..........................................................................................................47

3.3.4. Conceptual Framework of the Study ..............................................................50

3.4. The Specific Variables used in this Study..............................................................52

3.4.1. Variable Specifications used in Measuring the Efficiency of Farms............52

3.4.2. Variable Specifications used in Measuring the Environmental and Energy

Efficiency of Edible Canna Farms............................................................................55

Chapter 4 Results and Discussion..............................................................................58

4.1. Study I: Evaluation of Technical, Scale, Economic and Allocative Efficiency of

Edible Canna Farms using Two-stage Data Evelopment Analysis (DEA)............58

4.1.1. Descriptive statistic...........................................................................................58

4.1.2. The Efficiency level of Edible Canna Production in Backan Province......60

4.1.3. Factors Influence on the Efficiency of Edible Canna Farms in Backan

Province.......................................................................................................................63

4.1.4. Estimates Yield loss of Edible Canna Production in Backan Province by

Regions........................................................................................................................67

4.1.5. Summary of Study I.........................................................................................70

X

4.2. Study II: Evaluation of Environmental Efficiency and Its Determinants of

Edible Canna Production using Translog Frontier Production Function Model....71

4.2.1. Descriptive Analysis........................................................................................71

4.2.2. Technical Efficiency of Edible Canna Farms and Determinants..................75

4.2.3. Environmental Efficiency of Edible Canna Farms and Determinants.........79

4.2.4. Factors Influencing on Environmental Efficiency of Edible Canna Farms in

Backan Province.........................................................................................................81

4.2.5. Summary Study II............................................................................................82

4.3. Study III: Evaluation of Energy Efficiency and Optimum Energy Requirement

for Edible Canna Farms using DEA Approach........................................................84

4.3.1. Energy Efficiency of Edible Canna Farms in Backan Province ...................85

4.3.2. Energy Efficiency of Edible Canna Farms under Different Farm size ......91

Chapter 5 Conclusion and Policy Recommendations.............................................99

5.1. Conclusions..............................................................................................................99

5.2. Policy Recommendations......................................................................................100

5.3. Limitations of this Study .......................................................................................101

5.4. Recommendations for Future Study.....................................................................102

References.....................................................................................................................103

Appendices...................................................................................................................119

Bio-Sketch of Author..................................................................................................139

XI

List of Tables

Table 2.1. Area and productivity of edible canna production in Backan province

during 2016-2018.................................................................................. 15

Table 2.2. Summary of empirical studies used two-stage DEA on analyzing the

efficiency in agricultural production..................................................... 22

Table 2.3. Summary of empirical studies on energy efficiency in agricultural

production using DEA approach........................................................... 25

Table 2.4. Summary of some studies on evaluation the environmental

efficiency in agricultural sector using SFA approach........................... 30

Table 3.1. The sample size of the study ............................................................ 35

Table 3.2. The description of variables were used to analyze the efficiency of

edible canna farms................................................................................. 56

Table 4.1. Descriptive statistic of production and socioeconomic variables of

edible canna farms................................................................................. 59

Table 4.2. The Frequency distribution of efficiency scores of edible canna

farms in Backan province ..................................................................... 61

Table 4.3. The efficiency scores of edible canna farms in Backan province by

region..................................................................................................... 62

Table 4.4. Summary of returns to scale of edible canna farms....................... 63

Table 4.5. Factors influencing efficiency scores of edible canna farms......... 66

Table 4.6: Estimated yield loss of edible canna production in Backan province

by regions.............................................................................................. 68

Table 4.7. Descriptive statistics of socioeconomic variables of the sample... 72

XII

Table 4.8. Descriptive statistics of production activity variables of the

sample.................................................................................................... 74

Table 4.9. Maximum likelihood estimates for parameter of translog production

function ................................................................................................. 77

Table 4.10. The output elasticity with respect to input variables ................... 78

Table 4.11. The distribution of technical efficiency (TE) levels of edible canna

farms in Backan province ..................................................................... 79

Table 4.12. The distribution of environmental efficiency of edible canna farms

in Backan province................................................................................ 80

Table 4.13. Truncated regression estimates for factors influencing on EE of

edible canna farms................................................................................. 81

Table 4.14. Energy equivalents of input and output variables........................ 85

Table 4.15. Input and output energy used in edible canna production ........... 86

Table 4.16. The ratio of energy input and energy output in edible canna

production (by regions)......................................................................... 87

Table 4.17. The frequency distribution of efficiency scores of edible canna

farms (by regions)................................................................................. 88

Table 4.18. The energy input target and saving energy for edible canna

production in Backan province, Vietnam ............................................. 90

Table 4.19. The amount of energy inputs and output used in edible canna

production by different farm size.......................................................... 92

Table 4.20. The ratio of energy inputs and output in edible canna production

under different farm size ....................................................................... 93

XIII

Table 4.21. Frequency distribution of efficiency scores of edible canna farms

under different farm size ....................................................................... 94

Table 4.22. The energy target and saving energy for edible canna production in

different farm size ................................................................................. 96

XIV

List of Figures

Figure 1. Flowchart of research............................................................................ 6

Figure 2. Adventitious roots which generate in pairs (right) from the rhizome

and a part of root (left)...................................................................... 11

Figure 3. Edible canna production in Backan province, 2014-2018 .............. 16

Figure 4. The map of Backan province with two study districts.................... 32

Figure 5. The structure of economic sectors of Backan province from 2016 to

2018................................................................................................... 34

Figure 6. Conceptual framework of the study................................................. 51