WHAT PISA 2012 CAN CONTRIBUTE TO VIETNAMESE EDUCATION REFORM?
Ly T Pham (2014)
Published in Journal of Science, HUFLIT University No. 23. 2014
In 2012, Vietnam participated in the Program for International Students Assessment (PISA) for the first time; and ranked 17th among the 65 participating countries and territories. However, PISA is not meant to be a ranking tool, but rather it is a large-scale world-wide survey aimed at discovering what 15 year olds know and what they can do with what they know, to provide information to policy makers. The results are available by gender, family background, school experiences, parent expectations, teacher-student communication, and policy practices. This paper analyzes some selected aspects of the PISA results that might have implications for the Vietnamese educational reforms. While the overall test results for Vietnamese students were high, some analysis of the results would support the common belief that Vietnamese students are good at theory but not the application of knowledge. Over 85% of student reported that they study mathematics by instrumental motivation. More worryingly, almost 60% of the Vietnamese students said they do not think that other friends like them. This calls attention to the lack of development of social emotions and intrinsic motivation. Such a conclusion does not reflect all PISA datasets, but only results from the analysis of selected variables. More studies are needed to explore the full implications for PISA results to inform the Vietnamese education reform process in term of improved curriculum design, communication approaches between teacher and students, assessment methodologies, and opportunities for disadvantage populations.
It is necessary to understand the relative attributes of measurements before looking at their implications. First, do the PISA results for Vietnam reflect the performance of the education system? One can find several comments in the Vietnamese media about how the careful preparation for PISA in Vietnam might skew the results compared to the real situation. This sounds reasonable, especially in the context of the Asian culture, which focuses on “learning for the exams” rather than “learning to know, to work and to live with others”. It is common that Vietnamese students learn to please their parents not for their own motivation. Asian students are known as “test takers” who are well trained in taking tests. Their testing skills are so good that the testing results might exceed their true capacity in reality. An American professor who lived in Vietnam over 20 years said that he has met many people with TOEFL scores above 500 but with whom it was difficult to have a conversation in English. Therefore, there may be a gap between PISA performance results and reality.
A possible recommendation would be for the Ministry of Education and Training (MOET) to use the PISA survey and testing again in the same way or to apply PISA methodologies to existing national assessments, and ensure that participating students have never been trained building PISA testing skills. Analyzing these results would probably provide valuable information about what Vietnamese students know and what they can do with this knowledge. This finding will be an important resource for reforms on curriculum, teaching methodology, students performance assessments and relevant policies.
To be fair, training on taking PISA has had positive impacts on both teachers and students in Vietnam. It helps raise awareness about the application knowledge in real life. PISA’s approaches and methodologies are positive indicators for MOET and teachers in improving curriculum and teaching methods towards more practical and applied skills.
Second, PISA evaluates students knowledge and skills by testing Reading, Maths and Science only. It does not measure other competencies. In other words, PISA measures the basic knowledge of 15 years old students and their capacity of applying knowledge for life; it does not measure the whole educational outcome or products, let alone competencies of skilled employees. Therefore, it should be cautious to attribute PISA results to the excellence of an education system.
Third, international benchmark should be seen relatively. PISA tests are a mixture of open-ended and multiple-choice questions that are organised in groups based on a passage setting out a real-life situation; however something familiar to students of a country that might be strange and hardly understandable to those of another country. Though PISA organizers are aware of such differences in the process of making questionnaires and testing, these differences cannot be eliminated.
It is worthy of notice that PISA dataset includes not only testing results but also surveys based on a set of questionnaires on (1) the students’ backgrounds; (2) schools and learning experiences and (3) the broader school system and learning environment. These data are invaluable to understand the existing problems in a national education system. Analysis of these data in multi dimensions is very much needed. Beside testing results of 69 countries/economies, PISA 2012 produced 4 key reports: (1) What Students Know and Can Do: Student Performance in Mathematics, Reading and Science; (2) Excellence through Equity: Giving Every Student the Chance to Succeed ; (3) Ready to Learn: Student Engagement, Attitudes and Motivation; and (4) What Makes Schools Successful? Resources, Policies and Practices. I am especially interested in the Vietnamese students experiences. This paper is an attempt at analyzing data on what Vietnamese students experience at schools and how they learn.
What do we see through the Vietnamese students experiences?
“Students’ engagement with school, the belief that they can achieve at high levels, and their ability and willingness to do what it takes to reach their goals not only play a central role shaping students’ ability to master academic subjects, they are also valuable attributes that will enable students to lead full lives, meeting challenges and making the most of available opportunities along the way. In other words, much more is required of students – and adults – than just cognitive proficiency”.
This paper is based on data collected through student questionnaires – that is, self reported data, by principals of participating survey schools, and in some countries by parents as well. The survey aims to understand the behaviors, beliefs, and drivers of students in their learning practices. Measuring the students engagement, attitudes and motivations, as well as the influence of family and school in shaping these values, is a difficult task. It is even more complicated across countries because a behavior seen normal or expected in a particular country might be seen unacceptable somewhere else.
The students engagement vis-à-vis their school in Vietnam
The engagement to the school is measured by truancy and holding positive attitudes towards school, as in the following indicators: (i) how many times arriving late to school or skipping some classes or the whole day during the two weeks prior the test date; (ii) sense of belonging to the school; (iii) positive attitudes towards their school. Data analysis points out a strong correlation between the above factors and the students performance whether related to gender or social-economic background of the students.
In some countries, over half the students reported at least once arriving late to school during two prior weeks, such as Uruguay, Bulgaria, Costa Rica, Latvia, Sweden, Portugal, Israel, Chile, Peru and Tunisia; while this percentage is below 15% in Hong Kong, Japan, and 16.2% in the case of Vietnam.
The percentage of students who reported having not skipped classes or days of school in Vietnam is 93.4%; only lower than that of some other Asian countries/economies such as Japan (97.1%), Korea (97.1%), Hong Kong (96.9%), Shanghai (96.6%), Macao (94.%). In contrast, the OECD average is 82.2% and in some countries such as Uruguay, only 40% students reported having not skipped class or days of school in two weeks prior test date.
It could be argued that the two indicators (arriving late to school and skipping classes) are influenced by the students’ family background and the cultural context of each country. In most Asian countries, the pressure and expectations put on student learning by family are high. School discipline is also strict. Therefore, the high percentage of Vietnamese students reported having not skipped class or a day of school might reflect the pressure and expectation rather than students engagement to the school.
Arriving late to school, skipping class or a day of school are signs of lack of interest in learning and lead to negative consequences in the learning performance of students. Across OECD countries, the difference in mathematics performance that is associated with skipping classes or days of school is 37 score points; in Vietnam that difference is 42.3 score points. Low performance is also associated with the disadvantaged background of students.
An important indicator for measuring student engagement is the sense of belonging. Traditionally, the family is the main environment for social emotional development. This has been changing in recent years. Teenagers seek social acceptance outside their family more than before. As the OECD report mentioned:
“Indicators of social connectedness can show the extent to which families, schools and education systems foster overall student well-being. A sense of belonging reflects how connected students feel with their school and peers. Students tend to thrive when they form positive relationships with peers, feel part of a social group, and feel at ease at school. A lack of connectedness can adversely affect students’ perceptions of themselves, their satisfaction with life, and their willingness to learn and to put effort into their studies”.
In Vietnam, 81.73% of students feel that they belong, 91.38% of students agree or strongly agree that they can make friends easily, and 68.04 % of students disagree that they feel like an outsider or feel left out of things. Some 84.86 % of students feel happy at school, 78% are satisfied with school, and 61% believe that conditions are ideal in their school. Table 1 shows the degree of engagement to the school of Vietnamese students, compared with the OECD average. The results for Vietnamese students’ sense of belonging is greater than OECD countries students. However, the disparity between the percentage of students who reported “I feel happy at school” (84.86%) and “Things are ideal in my school” are worthy of attention. More remarkable is that the percentage of students who reported “I feel like an outsider at school” (11.17%) and “Other students seem to like me” (40.54%) seem to be conflict with the high percentage of students who reported “ I feel happy at school” (84.86%), “I am satisfied with my school” (89.37%). We pay special attention to the fact that only 40.54% of Vietnamese students reported that other people seem to like them, while in contrast in OECD countries 87.30% of the students have that feeling. This great disparity is worthy of mention and might be a sign of a serious problem of the system.
The logical inconsistency of the data calls for great care when interpreting its implications in the case of Vietnam.
Figure 1. Vietnamese students ‘sense of belonging to the school
Drivers and motivations of Vietnamese students
Figure 2.1. and Table 2.1 show that instrumental motivations dominate over the instrinsic ones. As Figure 2.1 and Table 2.1 point out, 66% of Vietnamese students agree or strongly agree that they do mathematics because they enjoy it while the OECD average is just 37.62%. and 79.21% reported that they are interested in the things they learn in mathematics. However, 87.68% of Vietnamese students see mathematics as an important subject for them because they need it for what they want to study later. Other instrumental motivations are also accounted high percentage of students who reported that they agree or strongly agree: “I will learn many things in mathematics that will help me get a job” (89.33% versus OECD average 66.57%); “Learning mathematics is worthwhile for me because it will improve my career (prospects, chances)” (87.70% versus OECD average 77.28%). However, parent influence on student views on studying mathematics in Vietnam is the same as that of OECD average. The statement “My parents believe it’s important for me to study mathematics” has 86.66% of Vietnamese student agreeing or strongly agreeing with, versus the OECD average 89.33% .
Figure 2.1. Motivations of Vietnamese students (The percentage of Vietnamese students reporting that they agree/strongly agree with these statements).
There is a clear relation between these motivations and mathemetics performance of Vietnamese students. Table 2.2 and Figure 2.2 shows that those who studies math because they enjoy it are those who attain the best performance in all of three subjects (reading, math and science) and their performance is much higher than that of students who reported that they study math as an instrument to achieve other goals. Obviously intrinsic motivations determine better learning performance. However, more than 85% of Vietnamese students study mathematics for instrumental motivations.
Figure 2.2. Motivations of Vietnamese students versus mathematics performance
Vietnamese students’ attitude towards school
One out of three Vietnamese students participating in the survey agree or strongly agree that “School has done little to prepare me for adult life when I leave school”. Though almost 90% of students agree/strongly agree that school has helped them confidence to make decisions, and only 6.65% disagree with this statement, these students perform much better than others. Similarly, 90.05% of students agree/strongly agree that school has taught them things which could be useful in a job; interestingly enough, these “dissidents” get much greater scores in all tests. These data imply that Vietnamese students lack critical thinking seriously while this characteristic seems to be an important factor for learning achievement.
Figure 3. 1. Vietnamese students attitude towards school
Figure 3.2. Association between students self report on attitude towards school and their performance
How strong is the confidence of Vietnamese students in applying mathematics knowledge to do tasks
PISA questionnaires provide some questions in which students need to use mathematics knowledge to find answers; and ask the students how confident they feel about having to do these mathematics tasks. Figure 4 and Table 4 shows the results for Vietnam, compared with the OECD average. Three situations in which Vietnamese students have the greatest level of confidence are solving an equation (89.28% of students reported that they feel very confident/confident for doing that), calculating how many square meters of tiles are needed to cover a floor (85.22%), and calculating how much cheaper a TV would be after a 30% discount (82.11%). It is perhaps because these examples are familiar to the students. The situations in which the Vietnamese students have the least confidence are calculating the petrol consumption rate of a car (only 41.66% of students having some confidence); finding the actual distance between two places on a map with a 1:10,000 scale (only 41.66%); and using a train timetable to work out how long it would take to get from one place to another (46.31% of students are confident); perhaps because these situations are unfamiliar to Vietnamese students. At the age of 15, Vietnamese students have no chance to drive a car / motorbike of their own, or traveling a long way alone, so they might have never dealt with these aspects.
In any event, these findings imply that Vietnamese students are strong theoretically and weak practically. This is the result of motivations learning towards the tests rather than for dealing with practical issues. In contrast, OECD countries students are very confident in using a train timetable to work out how long it would take to get from one place to another (80,46% versus 55,18% of Vietnam) and understanding graphs presented in newspapers (78,37% versus 54,33% of Vietnam).
Figure 4. How confident Vietnamese students feel about having to do some mathematical tasks- The percentage of Vietnamese students reported that they are confident/very confident having to do these tasks.
Several factors help explain Vietnamese students performance and understand how the education system is operating, thanks to the PISA 2012 dataset. PISA 2012 questionnaires provide valuable information about education practices and how school/family shaping students self-beliefs, drivers, motivations and attitude towards school, and ultimately influence their performance and competencies. The dataset also provides information on students’ background, the ways parents communicate with children, their expectations regarding children learning, etc. All of these factors are associated with building capacity for our future citizens. A set of studies to analyse these linkages is very much needed.
The question “Where is our relative standing in the world?” is not so as important as the question “What shortcomings do we have?”, because only the second one can help improving the education system for achieving better outcomes. A high rank can bring proudness but not wealth and prosperity. Only true capacity of human resource can create competitive advantages and promote development.
Participating in PISA will be useful to Vietnamese educational reforms if the Vietnamese people do not take it as a race for a high rank for national pride reasons or to avoid criticism on the weaknesses of the current education system. It would be better to see our participation in PISA 2012 as a great opportunity to learn about of students learning performance based on the application of concrete knowledge. More importantly, this is an invaluable opportunity to analyse the problems of the present national education system and initiate appropriate policies to improve it.
The PISA 2012 dataset can be analyzed along many dimensions. The six OECD reports mentioned above are helpful for Vietnam to consider critical issues such as education access for the disadvantage population; the goals of education; teaching/learning/assessment practices; resource utilization, and national policies.
The above analysis of student engagement, motivations, attitudes towards school and their influence on students performance point out some problems worthy of considering. 17% of Vietnamese students feel lonely at school; see themselves as outsiders, and almost 60% do not think that other students like them. The lack of critical thinking is also problematic. Instrumental motivations can help students doing well in their tests but do not help them, in the long run, to develop creativity and professional capacity. This finding is consistent with the results of studies on student confidence in using mathematics in life. These should ring an alarm among policy makers and educators. Many more studies are needed to translate this understanding into national policies which can help improving educational results.
The author of this report would like to thank her colleagues Tran Quy Phi and Ha Tan Duc for their contributions technically. Special thanks go to Dr. Jamil Salmi for giving comments, feedback and review the English version of this article.
Table 1. Vietnamese students’ sense of belonging
|Disagree (%) (3)||Strongly disagree(%)(4)||Missing data (%) (5)||Vietnam
|1||I feel like I belong at school||16.30||65.43||15.86||1.10||1.22||81.73||79.7|
|2||Other students seem to like me||3.27||37.27||50.58||8.19||0.68||40.54||87.3|
|3||I make friend easily at school||21.89||69.49||7.48||0.52||0.62||91.38||85.49|
|4||I feel lonely at school||0.96||5.12||58.52||34.59||0.80||6.08||8.75|
|5||I feel like an outsider (or left out of things) at school||1.17||10.00||63.41||24.63||0.80||11.17||12.20|
|6||I feel happy at school||16.48||68.38||12.5||1.54||1.10||84.86||68.12|
|7||Things are ideal in my school||12.36||55.04||29.01||2.77||0.82||67.40||69.84|
|8||I feel akward and out of place at school||1.17||10||63.41||24.43||0.8||11.17||13.2|
|9||I am sastified with my school||29.95||59.42||9.17||0.84||0.62||89.37||76.68|
Table 2.1. Vietnamese students’ motivations for learning mathematics and test results
|1||I do mathematics because I enjoy it|
|Strongly agree (%)||13.8||521||535||545|
|Strongly disagree (%)||1.62||504||504||529|
|Missing data (%)||1.2||471||470||490|
|2||Mathematics is an important subject for me because I need it for what I want to study later on|
|Strongly agree (%)||28.84||520||525||540|
|Strongly disagree (%)||0.91||457||453||488|
|Missing data (%)||0.63|
|3||I will learn many things in mathematics that will help me get a job|
|Strongly agree (%)||26.72||514||518||532|
|Strongly disagree (%)||0.89||463||453||482|
|Missing data (%)||0.65|
|4||My parents believe it’s important for me to study mathematics|
|Strongly agree (%)||23.75||525||533||546|
|Strongly disagree (%)||0.84||469||450||480|
|Missing data (%)||0.56|
|5||My parents believe that mathematics is important for my career|
|Strongly agree (%)||23.19||521||529||543|
|Strongly disagree (%)||0.92||466||465||494|
|Missing data (%)||0.56|
|6||Learning mathematics is worthwhile for me because it will improve my career <prospects, chances>|
|Strongly agree (%)||30.09||519||523||538|
|Strongly disagree (%)||0.85|
|Missing data (%)||0.79|
|7||I look forward to my mathematics lessons|
|Strongly agree (%)||7.17||510||520||533|
|Strongly disagree (%)||2.52||494||499||525|
|Missing data (%)||0.74|
|8||I enjoy reading about mathematics|
|Strongly agree (%)||14.83||518||535||543|
|Strongly disagree (%)||1.22||481||480||512|
|Missing data (%)||0.77|
|9||I am interested in the things I learn in mathematics|
|Strongly agree (%)||17.2||517||526||538|
|Strongly disagree (%)||0.85|
|Missing data (%)||0.72|
Table 2.2. Vietnamese students’ motivations for learning mathematics (compared OECD average)
|I do mathematics because I enjoy it||13.8||52.78||30.61||1.62||1.2||66.58||37.62||32.23||61.05|
|Mathematics is an important subject for me because I need it for what I want to study later on||28.84||58.84||10.78||0.91||0.63||87.68||65.4||11.69||33.33|
|I will learn many things in mathematics that will help me get a job||26.72||59.43||12.31||0.89||0.65||86.15||66.57||13.2||28.84|
|My parents believe it’s important for me to study mathematics||23.75||62.91||11.93||0.84||0.56||86.66||89.33||12.77||9.45|
|My parents believe that mathematics is important for my career||23.19||60.22||15.11||0.92||0.56||83.41||79.23||16.03||19.35|
|I am interested in the things I learn in mathematics||17.2||62.01||19.22||0.85||0.72||79.21||52.35||20.07||46.27|
|I look forward to my mathematics lessons||7.17||50.48||39.09||2.52||0.74||57.65||35.72||41.61||63.01|
|I enjoy reading about mathematics||14.83||60.7||22.47||1.22||0.77||75.53||30.32||23.69||68.67|
|I am interested in the things I learn in mathematics||17.2||62.01||19.22||0.85||0.72||79.21||52.35||20.07||46.27|
Table 3.1. Vietnamese students attitude towards school and test results
|1||School has done little to prepare me for adult life when I leave school.|
|Strongly agree (%)||4.59||485||491||509|
|Strongly disagree (%)||11.95||507||510||529|
|Missing data (%)||0.92|
|2||School has helped give me confidence to make decisions.|
|Strongly agree (%)||22.85||499||498||517|
|Strongly disagree (%)||0.49|
|Missing data (%)||1.08|
|3||School has taught me things which could be useful in a job|
|Strongly agree (%)||38.28||499||498||520|
|Strongly disagree (%)||0.76|
|Missing data (%)||0.83|
|4||Trying hard at school will help me get a good job.|
|Strongly agree (%)||30.79||509||513||530|
|Strongly disagree (%)||0.47|
|Missing data (%)||0.73|
|5||Trying hard at school will help me get into a good <college>.|
|Strongly agree (%)||31.15||509||513||530|
|Strongly disagree (%)||0.28|
|Missing data (%)||0.76|
|6||School has been a waste of time.|
|Strongly agree (%)||1.32||462||476||487|
|Strongly disagree (%)||33.18||518||520||539|
|Missing data (%)||0.86|
Table 3.2. Vietnamese students attitude towards school (compared OECD average)
|Questions||Agree/strongly agree||Disagree/strongly disagree|
|Vietnam||OECD average||Vietnam||OECD average|
|1||School has done little to prepare me for adult life when I leave school.||26.87||28.88||72.21||69.28|
|2||School has helped give me confidence to make decisions.||89.26||75.15||6.65||22.87|
|3||School has taught me things which could be useful in a job||90.05||85.47||9.12||12.69|
|4||Trying hard at school will help me get a good job.||91.41||89.78||7.86||8.53|
|5||Trying hard at school will help me get into a good <college>.||87.29||91.98||5.95||6.24|
|6||School has been a waste of time.||4.64||11.31||84.5||66.73|
Table 4. Vietnamese students self report on feeling of confidence towards mathematics tasks
|Not very confident/not confident at all
|How confident do you feel about having to do the following mathematics tasks?||Very confident||Confident||Not very confident||Not confident at all||Missing data||Vietnam||OECD
|1||Using a train timetable to workout how long it would take to get from one place to another.||10.49||44.69||41.33||2.75||0.74||55.18||80.46||44.08||18.34|
|2||Calculating how much cheaper a TV would be after a 30% discount.||29.25||52.86||16.18||1.12||0.59||82.11||78.84||17.3||19.99|
|3||Calculating how many square metres of tiles you need to cover a floor||32.2||53.02||13.39||0.62||0.76||85.22||67.21||14.01||31.47|
|4||Understanding graphs presented in newspapers.||10.61||43.72||42.59||1.89||1.19||54.33||78.37||44.48||20.17|
|5||Solving an equation like 3x+5= 17.||53.23||36.05||9.16||0.93||0.63||89.28||74.08||10.09||14.6|
|6||Finding the actual distance between two places on a map with a 1:10,000 scale.||12.31||34.00||49.44||3.51||0.74||46.31||65.09||52.95||42.52|
|7||Solving an equation like 2(x+3) = (x + 3) (x – 3).||37.15||40.69||19.98||1.53||0.65||77.84||72.12||21.51||26.55|
|8||Calculating the petrol consumption rate of a car.||6.38||35.28||51.89||5.77||0.67||41.66||55.21||57.66||43.47|
 OECD (2013), PISA 2012 Results: Ready to Learn – Students’ Engagement, Drive and Self-Beliefs (Volume III), PISA, OECD Publishing.
 PISA Results Overview Report. http://www.oecd.org/pisa/keyfindings/pisa-2012-results-overview.pdf
 Vietnam Ministry of Education and Training. “PISA 2012 Report”: http://www.moet.gov.vn/?page=1.10&view=5458
 Baumeister, R. andM.R. Leary (1995), “The need to belong: Desire for interpersonal attachments as a fundamental human motivation”, Psychological Bulletin, Vol. 117, pp. 497–529.
 Báo Mới. PISA Viet Nam Country Director interview, Dr. Lê Thị Mỹ Hà. (Excellence in the testing as a way stimulating Vietnamese intellectual” (“Vượt trội trong kỳ thi PISA là cách khơi dậy trí tuệ Việt”). Nguồn: http://www.baomoi.com/Vuot-troi-trong-ky-thi-PISA-la-cach-khoi-day-tri-tue-Viet/108/12600122.epi
Báo Dân Trí. (“PISA Results of Vietnam make the whole world surprised”). “Kết quả PISA gây bất ngờ cho cả thế giới”. Nguồn: http://dantri.com.vn/giao-duc-khuyen-hoc/ket-qua-danh-gia-hoc-sinh-viet-nam-gay-bat-ngo-cho-ca-the-gioi-810913.htm
 Báo Người Lao Động. (“Does PISA Results refect the nature of what have beed tested?”)“Kết quả PISA có thực chất?” Nguồn: http://nld.com.vn/giao-duc-khoa-hoc/pisa-co-thuc-chat-20130103100212900.htm
 Báo Tia Sáng. (“The two extremes that should be avoided”)“Hai thái cực cần tránh”. Thứ trưởng Nguyễn Vinh Hiển trả lời phỏng vấn về PISA. Nguồn: http://tiasang.com.vn/Default.aspx?tabid=62&News=5049&CategoryID=6
 Christian Bodewig. “What explains Vietnam’s stunning performance in PISA 2012?. Nguồn: http://blogs.worldbank.org/eastasiapacific/what-explains-vietnam-s-stunning-performance-pisa-2012
 Chen, X., K.H. Rubin andD. Li (1997), “Relation between academic achievement and social adjustment: Evidence from Chinese children”, Developmental Psychology, 33, pp. 518–525.
 OECD, PISA 2012 Database: http://pisa2012.acer.edu.au/
 Fredricks, J.A., P.C. Blumenfeld and A.H. Paris (2004), “School engagement: Potential of the Concept, State of the evidence”, Review of Educational Research, Vol. 74, pp. 59-109.
 Fredricks, J.A. and J.S. Eccles (2006), “Is extracurricular participation associated with beneficial outcomes? Concurrent and longitudinal relations”, Developmental Psychology, Vol. 42, No. 4, pp. 698-713.
 Nguyễn Văn Tuấn. (“PISA is as skew as PISA tower”) PISA cũng chông chênh như tháp nghiêng. Nguồn: http://tuanvietnam.vietnamnet.vn/2013-12-09-pisa-cung-chong-chenh-nhu-thap-nghieng-