NISTEP REPORT No.159

Science Map 2010&2012
Study on Hot Research Area (2005 – 2010 and 2007- 2012)
By Bibliometric Method

July 2014
Research Unit for Science and Technology Analysis and Indicators
National Institute of Science and Technology Policy (NISTEP)

Ayaka SAKA and Masatsura IGAMI

This highlight is English Translation of the following report
Science Map 2010&2012 –Study on Hot Research Area (2005 ‐ 2010 and 2007 ‐2012） By Bibliometric Method –Ayaka SAKA and Masatsura IGAMI, National Institute of Science and Technology
Policy (NISTEP REPORT No. 159), July 2014

T ABLE OF CONTENTSTABLE OF CONTENTS ...................................................................................................................................... 1
1. OVERVIEW OF NISTEP’S SCIENCE MAP.................................................................................................... 2
2. OVERVIEW OF CURRENT SCIENCE AND THE STATUS OF JAPAN ................................................................. 4(1) THE STATUS OF SCIENTIFIC RESEARCH OBSERVED IN SCIENCE MAP 2012 ..................................... 4(2) INCREASING UBIQUITY OF INTER‐/MULTI‐DISCIPLINARY RESEARCH .............................................. 8(3) INTERNATIONAL COLLABORATION IS GETTING A COMMON MODE OF CREATION OF
HIGH IMPACT KNOWLEDGE EVEN IN LIFE SCIENCES ........................................................................... 10(4) JAPAN’S FALLING SHARE AND DIVERSITY IN THE SCIENCE MAP .................................................. 12
3. CATEGORIZATIONOF RESEARCH AREAS BY USING THE

SCI‐GEO

CHART ANDUNDERSTANDING CURRENT ACTIVITIES OF JAPAN...................................................................................... 14(1) CURRENT SITUATION OF JAPANESE S&T POLICY AND REASON WHY WE CREATED
THE SCI‐GEO CHART .......................................................................................................................... 14(2) CATEGORIZATION OF RESEARCH AREAS BY USING THE SCI‐GEO CHART .................................... 14(3) TRENDS

IN RESEARCH ACTIVITIES IN THE WORLD AND BENCHMARKING

COUNTRIES AS SEEN WITH THE SCI‐GEO CHART ............................................................................... 16(4) TRANSITION OF SCI‐GEO TYPES OVER TIME ................................................................................. 18(5) ANALYZING CHARACTERISTICS OF FUNDING BY USING THE SCI‐GEO CHART ............................ 20
4. X‐RAY IMAGES OF RESEARCH ACTIVITIES AT THE INSTITUTIONAL LEVEL ON SCIENCE
MAP 2012 ..................................................................................................................................................... 22
5. FUTURE WORKS ........................................................................................................................................ 25
SELECTED REFERENCES ................................................................................................................................ 27

1

1. O VERVIEW OF NISTEP’ S S CIENCE M AP
he “Science Map” is a map that shows a snapshot of scientific research in theTworld. The National Institute of Science and Technology Policy (NISTEP)

periodically created the map. Research areas receiving international attention (hotresearch areas) are quantitatively identified through an analysis of scientific paper
database and their relative relationship are visualized.
The mapping of knowledge is a growing area of research, and a variety of studies
are being conducted [Börner, Chen & Boyack, 2003 and references therein;
Leydesdorff and Rafols, 2009]. The main feature of the NISTEP’s Science Map is thatits unit of analysis is a hot research area rather than focusing on traditional fieldclassification, such as chemistry, physics, and materials science [Saka and Igami,
2007]. Research area level monitoring of scientific activities can provide policy
makers and university administrators with more concrete information regarding the
emergence of new concepts or viewpoints in science and about specific communities
of researchers.
NISTEP’s Science Map is created by the following three steps; (1) identification ofresearch areas through the clustering of top 1% highly cited papers based on the co‐citation analyses [Small and Sweeney, 1985a; Small et al., 1985b]; (2) visualization ofresearch areas by mapping; and (3) extracting research area keyword based on the
text‐mining of titles and abstracts of papers.
To create Science Map 2012, approximately 70,000 of top 1% highly cited papers
published in the six‐year span from 2007 to 2012 were used. The top 1% papers wereidentified for each year and each of 21 ESI journal fields except for multidisciplinary
field1. These top 1% highly cited papers were clustered to research areas by a two‐
step clustering (i.e., papers to research fronts, research fronts to research areas).
Through this process, we obtained 823 research areas in Science Map 2012.
In this report, papers making up each research area (i.e., the top 1% papers) arecalled “core papers.” Papers that cite core papers are called “citing papers.” “Citing
papers (top 10%)” refer to citing papers they are top 10% highly cited in the world asof the end of 2012. Core papers can be considered the papers that lead research areas.
Exhibit 1 shows a conceptual view of a research area. If we consider a research area
as a mountain, these core papers make up its summit. Citing papers could bethought as the foot of the mountain because they follow the core papers; accordingly,

1 Papers published in multidisciplinary journals were reclassified into either of 21 ESI journal fields based on theinformation of backward citations.

2the citing papers (top 10%) can be thought as the broad middle portion of themountain.
Exhibit 1 Conceptual view of a research area

In the past, we released Science Map 2002 (1997–2002), Science Map 2004 (1999–2004), Science Map 2006 (2001‐2006), and Science Map 2008 (2003–2008). In addition,
we have created Science Map 2010 (2005–2010) and Science Map 2012 (2007–2012).
In this highlights, we discuss the result of Science Map 2010 & 2012.
Overview of current science and the status of JapanThe status of scientific research observed in Science Map 2012
Increasing ubiquity of inter‐/multi‐disciplinary researchInternational collaboration is getting a common mode of creation of highimpact knowledge even in life sciences
Japan’s falling share and diversity in the Science Map
Categorization of research areas by using the Sci‐GEO chart and understanding
current activities of Japan
Current situation of Japanese S&T policy and reason why we created theSci‐GEO chart
Categorization of research areas by using the Sci‐GEO chart
Trends in research activities in the world and benchmarking countries as
seen with the Sci‐GEO chart
Transition of Sci‐GEO types over time
Analyzing characteristics of funding by using the Sci‐GEO chart
X‐ray images of research activities at the institutional level on Science Map 20123

2. O VERVIEW OF CURRENT SCIENCE AND THE ST ATUS OF J AP AN(1) T HE STATUS OF SCIENTIFIC RESEARCH OBSERVED IN S CIENCE M AP 2012

I

n Science Map 2012 (2007–2012), 823 research areas receiving international
attention (hot research areas) were identified; Exhibit 2 shows Science Map 2012.

The Science Map provides a bird’s eye view of the “mountains of scientific research”
formed by core papers accumulated.
SCIENTIFIC RESEARCH CONTINUES TO EXPAND

823 research areas are identified as hot research areas in Science Map 2012. The
number of research areas shows about 40% increase compared to that in Science
Map 2002 (598 research areas), representing active knowledge creation, an increasein the number of papers being published, around the world.
TREND OF SCIENTIFIC RESEARCHESFor Science Map 2012, we identified keywords that represent the characteristics ofeach of the 823 research areas based on the text‐mining of titles and abstracts ofpapers. To make it easier to grasp the outline of Science Map, we developed amethodology to aggregate research areas sharing common keywords (research area
groups) and depicted those groups on the map.

No.

Group of research areas

No.

Group of research areas

1

Cancer research

10Environment (Research on climate change)

2

Research on cardiovascular disease

11

Intersection of biological mechanism and nano‐scale phenomena (Life‐nano bridge)

3

Public health and physical activity

12

Energy generation by biological or chemical approach

4

Research on infectious diseases and immunology (incl. gene expression control)

13

Chemical synthesis

5

Gene expression control and regenerative medicine

14

Nanoscience (Approach from chemistry)6

Research on brain and neurological diseases

15

Nanoscience (Approach from physics)

7

Research on psychiatric disease

16

Solid state physics (Quantum information and optics)

8

Plant and microbiological research (incl. gene expression control)

17

Solid state physics (Magnetism and superconductivity)

9

Environment (Research on ecological system)

18

Particle physics and cosmology(Note 1)

(Note 2)Since the map is created by a force‐directed placement method, relative location of research areas isimportant, there is an arbitrariness in the direction of X and Y axes. In this report, we present maps inwhich life sciences are located in the upper left, while particle physics and cosmology are located in thebottom right.
White circles indicate the centers of research areas. Research areas had a weak linkage with other researchareas were positioned away from the center of the map; therefore they are not depicted in the map. Red
dotted lines show the groups of research areas. They are guides for general understanding of researchcontent. A research area included in a group is determined by whether the research area shares common
keywords with other research areas on the map. Thus, it is not implied that research areas that are outside
the groups are not important.

4

Exhibit 2 Science Map 2012

Data：

NISTEP conducted analysis and visualization (ScienceMap visualizer) based on ESI research front data
(N STPȱversion) byȱThomo Reuters.

5Research area groups related to life sciences are found in the upper left of the
Science Map, as depicted in Exhibit 2. “Cancer research” and “research on
cardiovascular disease” include keywords related to clinical research. The researchareas of “research on infectious diseases and immunology,” “gene expression control
and regenerative medicine,” and “plant and microbiological research” include
keywords related to gene expression regulation, showing an elucidation ofmolecular mechanisms is shared element of research among the three groups. In
addition, “research on brain and neurological diseases” as well as “research on
psychiatric disease” are closely positioned and therefore thought to be developing
cooperatively.
“Public health and physical activity” is located somewhat away from “research on
infectious diseases and immunology.” Other groups of research areas in life sciences
are conducted from the viewpoint of individual mechanisms and their control ormedical treatments, but “public health and physical activity” includes keywords
related to group health and preventative measures for public hygiene, indicating a
difference in the viewpoint from the former.
“Environmental research,” which is located below “plant and microbiologicalresearch” on the Science Map, has shown a visible change from 2002 to 2012. In
Science Map 2012, two research area groups were found, namely “environment(research on ecological system)” and “environment (research on climate change).”“Particle physics and cosmology” is located in the bottom right of the Science Map.
Starting from “particle physics and cosmology,” we can find the research area
groups of “solid state physics (magnetism and superconductivity),” “solid statephysics (quantum information and optics),” “nanoscience (approach from physics),”“nanoscience (approach from chemistry),” and “chemical synthesis” showing inter‐linkages of these research area groups. Compared with Science Map 2002, thenumber of research areas related to nanoscience has shown a sharp increase.
Between the groups of life sciences and nanoscience, there is a group of researchareas presenting the intersection of biological mechanisms and nano‐level
phenomena (i.e., the life‐nano bridge). Looking at changes in the map over timesince Science Map 2002, it is found that knowledge created in the life‐nano bridge isspreading to both the life sciences and nanoscience rather than some fusion researchappear and grow. In other words, this portion represents a true intersection of
biological mechanisms and nano‐level phenomena.
Another characteristic of Science Map 2012 is that at the intermediate position
between the research areas of “chemical synthesis,” “plant and microbiologicalresearch,” “environment (research on ecological system),” and “environment

6

(research on climate change),” we find a group of research areas related to thecreation of energy through biological and chemical approaches, including researchareas related to biomass and microbial fuel cells.
The Science Map also includes research areas not categorized into any research area
groups. A research area included in a group is determined by whether the researcharea shares common keywords with other research areas on the map. Thus, it is not
implied that research areas that are outside the groups are not important.

(COLUMN) THE RELATIONSHIP BETWEEN RESEARCH ACTIVITIESAND WHAT IS OBSERVED IN NISTEP’S SCIENCE MAPT

he Science Map provides a bird’s eye view of hot research areas. It can visualize growth,
integration, and divisions of the research communities for research areas that

continuously exist on the map; however, the Science Map is not a closed world. The Sea of
Science, a source of knowledge made up of all scientific papers produced in the world, exists
outside the Science Map. New notable research areas are formed and emerged from this Seaof Science and these research areas are monitored on the Science Map.
There are various phases in research, such as a phase heading toward practical application, aphase summarizing research findings, etc. From this viewpoint, we identify the following
three types of research areas not detected in the Science Map: (1) research areas that havetransitioned into technological phase such as those seen in patents; (2) research areas in asaturation phase; and (3) research areas in a steady state after the temporary boom. Even inthese undetected research areas, knowledge is still accumulated and does not disappear. In allthese patterns, the research area is expected to reappear on the Science Map if it begins toreceive new attention, for example, if there is a discovery that pushes the research into a newphase.
Thus, the Science Map extracts those research areas in which research is receiving extensive
attention and is in a progressive phase. This is a “cyclic system” and the system cannot workwithout the Sea of Science that surrounds the Science Map. Since research areas represent
activities of the communities of researchers who share common research interests, dynamics
such as changing generations of researchers and movement of researchers across researchareas would have some impacts on a cyclic system of Science Map.

7

(2) I NCREASING UBIQUITY OF INTER ‐/ MULTI ‐ DISCIPLINARY RESEARCH

U

nderstanding the trends in inter‐/multi‐disciplinary research is crucial to grasp
the present status of science. The proportion of inter‐/multi‐disciplinary

research areas among hot research areas has changed little since Science Map 2002
and stands at 26% in Science Map 2012.
Time‐series observation of the position of inter‐/multi‐disciplinary research areas in
the Science Map (shown in Exhibit 3) revealed that research areas localized inrelatively limited region in Science Map 2002 show gradual expansion over time.
In Science Maps 2002 and 2004, inter‐/multi‐disciplinary research areas wereconcentrated in life sciences. After Science Map 2006, many inter‐/multi‐disciplinary
research areas have appeared in nanoscience. The ubiquity of inter‐/multi‐
disciplinary research is increasing over time and these research areas are locatedacross the entire map in Science Map 2012.
What these findings indicate is that while the exchange of knowledge was common
within life sciences at the time of Science Map 2002, we also witnessed an increase insuch exchanges in non‐life sciences as well as between life sciences and non‐lifesciences. In other words, it remarks growing importance of the combination ofknowledge of different fields of science in the advancement of contemporary science.

8

Exhibit 3 Changes in the position of inter‐/multi‐disciplinary research areas on
the Science Map

Research areas of specificfields of science

More than60%

Inter‐/multi‐disciplinary
research areas

60% orless

A field accounts for more than 60%
of core papers of research areas(Note 1)

A field accounts for 60% or less core
papers of research areas

Circles represent research areas. If a specific traditional field accounts for less than 60% of core papers,
we define these research areas as inter‐/multi‐disciplinary research areas and show them with red circles.
(Note 2) The length corresponding with 10‐unit distances is shown on the map as a scale.
Data： NISTEP conducted analysis and visualization (ScienceMap visualizer) based on ESI research front dataȱȱȱȱȱȱȱȱȱȱȱȱȱȱȱȱǻ ȱǼȱ¢ȱȱǯȱ9

(3) I NTERNATIONAL COLLABORATION IS GETTING A COMMON MODE OF
CREATION OF HIGH IMPACT KNOWLEDGE EVEN IN LIFE SCIENCES

A

nalyses of the type of authorship in scientific papers showed the increasing ofinternationally co‐authored papers, which can be considered as an output of

an international collaboration. This observation indicates that research activities arebeing conducted across national and regional borders. By overlaying information ofinternational co‐authorship in core papers of each research area over the Science

Map, we analyzed current status of international collaboration in hot research areas.
Exhibit 4 displays the ratio of international co‐authorship in core papers overlaid on
Science Maps. The red color represents region where the ratio of international co‐
authorship is 40% or more. In Science Map 2002, the red colored region isconcentrated in “particle physics and cosmology;” however, the ratio ofinternational collaborations shows a gradual increase on the entire Science Map overtime.
An increase in the ratio of international co‐authorships has especially been clear inlife sciences. In contrast, the ratio of international collaboration has remained low in“chemical synthesis” and “nanoscience” from Science Maps 2002 to 2012. This showsthat the forms of research activities vary depending on the content of research andthat the ratio of international co‐authorships is not uniform on the Science Map.

10

Exhibit 4 Ratio of international co‐authorships overlaid on the Science Map overtime

(Note)

Data：

The regions where the ratio of international co‐authorship is 5% are shown in light blue; over 40% areshown in red; yellow circles and numbers represent locations and IDs of research areas where the ratio ofinternational co‐authorship in core papers are over 40%.
NISTEP conducted analysis and visualization (ScienceMap visualizer) based on ESI research front dataǻ ȱǼȱ¢ȱȱǯȱ11

(4) J APAN ’ S FALLING SHARE AND DIVERSITY IN THE S CIENCE M APW

e monitored three indicators to analyze Japan’s presence in scientificresearch.
The first indicator is the share of Japan and benchmarking countries incore papers that made up of all research areas (see Exhibit 5A). This is an indicatorthat shows a volume of papers that lead hot research areas. On Science Map 2012,
the UK (6.9%) and Germany (7.2%) lead Japan (4.1%). Furthermore, we observe thatJapan’s share is falling over time.
Second, by looking at the number of research areas Japan participating2 on Science
Maps, we analyzed Japan’s diversity in scientific research as shown in Exhibit 5B.
While the number of research areas in the Science Map increases, the number of
research areas Japan participating has stagnated, leading to a decline in the coverageon Science Maps (41% as of Science Map 2008 and 33% as of Science Map 2012).
There is a significant difference between the number of research areas Japan
participating and the UK and Germany participating.
Third, by analyzing the coverage in citing papers (top 10%), i.e., followers of the core
papers, we can check the size of research community of the second tier group. The
number of research areas each country participating in citing papers (top 10%) was
higher than that in core papers for all three countries, but the UK (720) and Germany(702) still show large advantage over Japan (607). This result indicates a lack of thesecond tier group in Japan compared to the UK and Germany.
Moreover, if we compare the ratio of the coverage in core and citing papers (top10%), we find that while Japan stands at 45% (274/607), the UK and Germany are at
70% (504/720) and 65% (455/702), respectively. How to facilitate the transition ofresearchers of the second tier group to the first tier group is another issue for Japan.

2 The participation to a research area is determined by whether or not a core paper (or a top 10% citing paper) of atarget country is included in a research area.

12

Exhibit 5 Japan’s presence on the Science Maps(A) Shares of Japan and benchmarking countries in core papers (18,515 core
papers for 823 research areas)

Share of Core papers

USA

Germany

UK

Japan

France

South
Korea

China

Science Map 2008

46.4%

7.2%

6.7%

5.3%

3.7%

1.0%

5.2%

Science Map 2010

42.4%

6.9%

6.9%

4.7%

3.9%

1.1%

6.4%

Science Map 2012

40.6%

7.2%

6.9%

4.1%

3.8%

1.4%

9.2%

(B) Changes in the coverage of research areas Japan, the UK, and Germany
participating. (1) One or more core papers, (2) One or more citing papers(top 10%)
Japan

ALL

Coverage of RAs

Germany

UK

Num. of
Num. of
Num. of Num. of
Coverage
Coverage
Coverage
RAs
RAs
RAs
RAs

Science Map 2008

Core papers

647

263

41%

388

60%

366

57%

(1) Science Map 2010

Core papers

765

278

36%

488

64%

447

58%

Science Map 2012

Core papers

823

274

33%

504

61%

455

55%

(2) Science Map 2012

Citing papers(Top10%)

823

607

74%

720

87%

702

85%

(Note 1)

Exhibit (A) shows the share of Japan and benchmarking countries in core papers that form all researchareas using fractional counting method.
(Note 2) The number of research areas in Exhibit (B) indicates the number of research areas in which the countryhas (1) one or more core paper and (2) one or more citing papers (top 10%).
Data： NISTEP conducted analysis and visualization (ScienceMap visualizer) based on ESI research front dataȱȱȱȱȱȱȱȱȱȱȱȱȱȱȱȱǻ ȱǼȱ¢ȱȱǯȱȱ13

3. C ATEGORIZ ATION OF RESE ARCH ARE AS BY USING THE S CI -GEO
CHART AND UNDERST ANDING CURRENT ACTIVITIES OF J AP AN(1) C URRENT SITUATION OF J APANESE S&T POLICY AND REASON WHY WE
CREATED THE S CI ‐GEO CHARTI

n recent discussions of science and technology policies in context of research

activities that produce scientific papers as an output of research, various issues

have been raised, including basic research as a seedbed of innovation, diversity inbasic research, and selection and concentration of resources; however, these policy
discussions are often conducted without sufficient quantitative evidences, andpolicies are often advanced based on past experience or measures taken abroad.
Unfortunately, Japan’s presence grasped on the Science Map is falling over the past
decade.
Due to current financial situation of Japan, the allocation strategy is critical in S&T
policy. In such a context, quantitative evidences should be constructed and policy
discussions and decisions should be made based on these evidences.
What research areas are responsible for diversity in basic research? Which researchareas are candidates for selection and concentration of resources? How should wethink about the balance between diversity in basic research and selection andconcentration of resources? To answer these questions, this Science Map introduces
the concept of Sci‐GEO chart (Chart represents geographical characteristics ofResearch Areas on Science Map).

(2) C ATEGORIZATION OF RESEARCH AREAS BY USING THE S CI ‐GEO CHART
Looking at the dynamic changes on the Science Map3, the mountain of scientificresearch can be classified into two portions. The first are relatively “hard” portions,where scientific research is continuously taking place and strong relationships withother research areas exist. The second are “soft” portions showing continuouschanges. To categorize these “hard” and “soft” portions, we introduced the conceptof the Sci‐GEO chart on the Science Map, as shown in Exhibit 6.
In the Sci‐GEO chart, research areas are categorized using continuity (time axis) andthe strength of relationships with other research areas (cognitive axis). As shown in
Exhibit 6, when there is continuity with the previous map, we categorize theresearch areas into “continent type,” which are strongly related to other research

3 A movie showing dynamic changes from Science Map 2002 to Science Map 2012 is available athttps://www.youtube.com/watch?v=ZjgvboKRE1o (in Japanese)14

areas, and “island type,” which have weaker relationships with other research areas.
In case there is no continuity with the previous map, we categorize those researchareas as “peninsula type,” which fill peripheral positions of “continent type”
research areas, and “small island type,” which have weaker relationships with otherresearch areas.

Exhibit 6 Categorizing research areas by using the Sci‐GEO chart

Sci‐GEO Chart（Chart represents geographical characteristics of Research
Areas on Science Map）

Science Map
Strong
Weak
Cognitive linkage with other RAs[Cognitive space]

Peninsula typeContinent type

Small island type

Island type

NO

YES

Continuity from the previous science map[Time](Note1)(Note2)

Regarding links with other research areas, research areas are said to be linked if the degree of normalized
co‐citation is 0.02 or more. Three or more links are considered to be a strong linkage. Two or less links are
considered to be weak linkages.
Continuity refers to 20% or more core papers overlapping between research areas in the Science Map
being compared.

15

(3) T RENDS IN RESEARCH ACTIVITIES IN THE WORLD AND BENCHMARKING
COUNTRIES AS SEEN WITH THE S CI ‐GEO CHART

A

mong the 823 hot research areas obtained in Science Map 2012, it is found that

40% of the research areas are small island type and 20% are continent type, as

depicted in Exhibit 7A. In contrast, looking at the number of core papers in the
research areas, we find that 50% are in continent type and less than 20% are in small
island type, reflecting large size of continent type research areas relative to small
island type research areas (60 core papers for continent type vs. 10 core papers forsmall island type)
Among the 274 research areas Japan participating, 90 are continent type, 55 arepeninsula type, 59 are island type, and 70 are small island type, as shown in Exhibit
7B. Comparing Japan, the UK, and Germany, we find the largest difference in thenumber of small island type research areas. Looking at the balance of Sci‐GEO types,
it is found that 26% of Japan’s participating research areas are small island type and
33% are continent type. The balance shows striking difference compared with thebalance of Sci‐GEO types in the world (40% small island type, 19% continent type).
These evidences pose crucial questions regarding how Japan should think of its“presence” in scientific research. Dose Japan need to increase research diversity as
seen through the number of research areas Japan participating? Or does Japan needto increase the volume of high impact papers to secure its share in the world?
Depending on this choice, desirable balance in Sci‐GEO chart will differ.

16

Exhibit 7 Comparison of Japan and benchmarking countries based on the Sci‐
GEO types(A) Balance of the number of research areas and the number of core papers
by Sci‐GEO type in Science Map 2012
100%
2,894

90%
80%

331
4,134

70%
60%

2,430
50%

191

40%
30%

141

9,057

20%
10%

160

0%
ALL RAs(823)
Continent typeALL core papers(18,515)

Peninsula type

Island type

Small island type(B) Number of each Sci‐GEO type research areas by country and theirbalance on Science Map 2012
Num. of each Sci‐GEO type research areas
by country in Scinece Map 2012

Balance of each Sci‐GEO type research areas inScinece Map 2012

900

100%

800

90%
80%

700
331
600

40%

38%

35%

60%

191

174
173

300
200
100

141

160

50%
129

Continent type

Data：

29%

23%

122

106

77

87

129

93

30%

59
55

81

20%

90

81
China
(322)

70

67

158

131

133

USA
(741)

UK
(504)

Germany
(455)

Japan
(274)

Island type

Small island type

Peninsula type

23%

23%

10%

19%
17%

17%

19%

21%

ALL
(823)

USA
(741)

22%
25%

24%

40%

0
ALL
(823)

26%

70%

281

500
400

28%

20%
21%

15%

26%

29%

33%

UK
(504)

Germany
(455)

Japan
(274)

Peninsula type

Island type

Small island type

25%

0%

Continent type

NISTEP conducted analysis and visualization (ScienceMap visualizer) based on ESI research front data
(NISTEP version) by Thomson Reuters.

17

China
(322)

(4) T RANSITION OF S CI ‐GEO TYPES OVER TIME

T

o look at the evolution of research areas by using the Sci‐GEO chart, weanalyzed the transitions of Sci‐GEO types of research areas between the

successive two Science Maps, as illustrated in Exhibit 8.
Small island type research areas account for 40% of research areas and therefore
they play major role in the diversity of research. Analyses of transitions among Sci‐
GEO types revealed that small island type research areas evolve to other Sci‐GEO
types over time, such as island type (slightly less than 30%) and continent type(slightly less than 10%); however, approximately 60% of the small island typeresearch areas are not detected on the subsequent Science Map, showing highly
active replacements. These facts suggest that the two points are crucial for
promoting research of small island type. First, an environment in which theseresearch areas can be actively generated must be created. Second, to allow thecontinuous development of promising small island type research areas, supportshould be provided at proper timing in order to increase the size of the community
participating in these research areas.
Approximately 60% of the continent type research areas also appear on thesubsequent Science Map as continent type. Slightly less than 20% of them showstransition to island type and those slightly more than 20% are not found on thesubsequent Science Map. Overall, 70% of continent type research areas continue,
showing a high degree of stability. Looking at continent type research areas from theviewpoint of continuity, we find that these research areas are more stable targets forresearch promotion in comparison with other type of research areas. However, large
size of research areas relative to the other Sci‐GEO types indicates fierce
international competition in the research areas. Therefore any measures to promoteresearch must consider the scale of resources to be invested as well as a balance
between competition and collaboration.

18

Exhibit 8 Features of each Sci‐GEO type research areas and the points to beconsidered for promoting research

Peninsula type
Number : 20% of RAs
Size: Medium
Stability : Intermediate

Number : 20% of RAs
Size: Large
Stability : Stable[Transition]
 More than 10%: Move to Island type
 Slightly Less than 50%: Move to Continent type

[Transition]
 Slightly less than 20%: Move to Island type
 60%: Remain to Continent type

Small island typeA)

Continent type

B)

Island type

C)

Number : 40% of RAs
Size: Small
Stability : Dynamic changes

Number : 20% of RAs
Size: Medium
Stability : Intermediate[Transition]
 Slightly less than 30%: Move to Island type
 Slightly less than 10%: Move to Continent type

[Transition]
 Slightly less than 40%: Remain to Island type
 10%: Move to Continent type

Science begins in small communities that competewith one another; some among those will becomelarger (however, in Japan, the weight is only 20%).

A) How to obtain diversity? → It includes RAs with a possibility ofgrowing larger in the futureB) How to select and support RAs that may grow larger in the
future?
C) How to maintain presence of Japan in these RAs and to achievescientific and social/economic impacts?

19(5) A NALYZ ING CHARACTERISTICS OF FUNDING BY USING THE S CI ‐GEO
CHART

R

esults presented so far suggested that optimal policies for promoting research(number of projects, research team scale, amount of research budget, etc.) differ

across the type of a research area as found through the Sci‐GEO chart. Next, weanalyzed the relationship between funding and the Sci‐GEO types on the Science

Map. In particular, we overlaid the positions of scientific papers that got support
from Japan’s two major competitive funds — grants‐in‐aid for scientific research(“KAKENHI”) and the ones by Japan Science and Technology Agency (JST) — on
the Science Map. In the following results, “WoS‐KAKEN paper” refers to a paperthat is listed in a report of a research project supported by KAKENHI. “JST paper”
refers to a paper in which JST is listed as one of affiliation of authors.
Research areas including WoS‐KAKEN papers account for approximately 70% of theresearch areas Japan participating, as shown in Exhibit 9. In other words, KAKENHI
is responsible for a large portion of the diversity of research in Japan. Research areas
including JST papers largely overlap with research areas including WoS‐KAKEN
papers; among them, the more overlapping is found in island and continent typeresearch areas. While it has often been pointed out that KAKENHI supports thediversity of Japanese research and JST strategically promotes research, we have now
shown this picture quantitatively.
As shown in previous analyses, Japan’s share of papers is decreasing and diversityof research is not catching up the expansion of scientific research in the world.
Discussions should be made regarding how to effectively bridge funding agencies inorder to increase the presence of Japanese research and how to provide appropriate
amount of research funds reflecting stage of evolution and characteristics of researchareas. At the same time, the effort to accumulate additional evidences for further
policy discussions is inevitable as described in future works.

20

Exhibit 9 The number of research areas including WoS‐KAKEN papers and JST
papers by Sci‐GEO type on Science Map 2008
Number of research areas

Small island type

Science Map
2008

JAPAN
participating

248

64

WoS‐KAKEN
papers included

JST papers
included45

7

Share of overlapping RAs
in RAs WoS‐KAKEN papers
includedOverlapping RAs 6
Island type

169

77

Peninsula type

92

35

59

27

Overlapping RAs 27
25

4

Overlapping RAs 3
Continent type

138

87

74

25

Overlapping RAs 24
Total

647

263

203

63

Overlapping RAs 60(Note1)(Note2)(Note3)
Data：

This analysis used the Science Map 2008.
“WoS‐KAKEN paper” refers to a paper that listed in a report of a research project supported by
KAKENHI.
“JST paper” refers to a paper in which JST is listed as one of affiliation of authors.
NISTEP conducted analysis and visualization (ScienceMap visualizer) based on ESI research front data
(NISTEP version) by Thomson Reuters.

21

13%
46%
12%
32%
30%

4. X- RAY IMAGES OF RESE ARCH ACTIVITIES AT THE INSTITUTIONALLEVEL ON S CIENCE M AP 2012As shown in Exhibit 10, we include information regarding each of the 823

research areas found on Science Map 2012, such as the information of thenumber of core papers, the share of benchmarking countries, keywords, and the
proportion of internationally co‐authored papers4.
We also visualize research activities of 153 Japanese universities and public research
institutions on Science Map 2012. It is a kind of X‐ray image enabling us to capture
institutional‐level research activities in Japan. By using this data, we compare thecharacteristics of Japan’s universities and public research institutions from aquantitative viewpoint. Exhibit 11 presents the Science Map Research Activity Sheetof University of Tokyo.
We analyze how research activities of the 153 universities and public research
institutions overlapped on the Science Map and find that there are research areas
over 20 institutions participating (as shown in Exhibit 12). We also find that there
are approximately 90 research areas in which only one institution are participating,indicating the research area level analysis well reveals an individual characteristic ofuniversities and public research institutions.
Here, we will provide examples of how to utilize the data. In a situation where an
institution sets integrated research agenda to promote research, they can confirm if
their institution covers research areas that would fit the research agenda or how
distant are the candidate researchers on the map, using the tool as a common basisof discussion. In addition, this report includes accession number (unique ID of
papers in the Web of Science) of core and citing papers (top 10%) of 153 universities
and public institutions for searching publications. If the institution contributes invarious research areas, it could classify publications by department or research units
and analyze their locations on the map in order to visualize the characteristics of theinstitution.
We hope that utilization of this quantitative monitoring tool will deepen discussion
and will increase the good practices at individual research institutions.
Consequently, we will see an accumulation of knowledge related to researchplanning based on such evidence. The experience would be beneficial for further
advancement of Science Map research, thus we would be grateful to hear about
practical cases on how this tool is being utilized.

4

The information is only available in Japanese.

22

Exhibit 10 Detailed research area data on the Science Map 2012

Exhibit 11 Science Map Research Activity Sheet

Data：

NISTEP conducted analysis and visualization (ScienceMap visualizer) based on ESI research front data
(NISTEP version) by Thomson Reuters.

23

Exhibit 12 Distribution of Japanese research institutes in research areas of the
Science Map 2012

100

Nnumber of research areas

90
80
70
60
50
40
30
20
10
0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 19 21 22 23 24 36 43
Number of research institutes participating
among 153 research institutes
Data：

NISTEP conducted analysis and visualization (ScienceMap visualizer) based on ESI research front data
(NISTEP version) by Thomson Reuters.

Exhibit 13 Elements necessary when considering the activities of research24

5. F UTURE WORKS

F

inally, we discuss future work. In Exhibit 13, we summarized the elements
necessary when considering the activities of research based on our past studies

and discussions with government officials and high‐level policy makers. When
analyzing research activities, the following five elements should be taken into

consideration; (1) boundary setting of content, (2) motivation, (3) Sci‐GEO type, (4)the composition of research team, and (5) the kind of supporting funds.
In this report, we tried to overlay various information of the above mentioned
research activities on the Science Map. In other words, by linking the five elements
to the Science Map, we attempt to obtain an integrated understanding of research
activities. It is expected that our understanding of these factors will bring aqualitative change on our discussions of S&T policies. For example, in discussing
internationalization of research, the Science Map shows how the status ofinternationalization differs depending on a research area and how the UK and
Germany have gained their coverage of research areas through internationalization.
In addition, another study suggests that compared with Edison‐type research, inwhich solving specific issues in real life is the primary motivation of research, Bohr‐type research projects, which is motivated by the pursuit of basic principles, have ahigher likelihood of evolving to an international collaboration. These data is
expected to clarify the meaning of internationalization in S&T policies.
Linking data of the types and amounts of research funding to the Science Map willlead to the in‐depth understanding of the appropriate funding and team sizes forpromoting research. As seen in the Sci‐GEO chart analysis, 40% of research areas
receiving global attention are classified as small island type, which are often to be
replaced, and approximately 20% are continent type, which have strong
relationships with neighboring research areas. The allocation of research funding
should be re‐examined; depending on the balance between these two types ofresearch Japan would pursuit.
After around ten years of trial and error, we have obtained effective tools andindicators to analyze research activities, such as that given in this report. In future
work, by linking various elements of research activities such as those shown in
Exhibit 13 to the Science Map, we would be able to further deepen our analysis.

25

In summary, we outline three issues for future work as following.
LINKING THE SCIENCE MAP AND FUNDING DATA
Adding funding data to the Science Map will provide valuable information. By
overlaying WoS‐KAKEN paper data on Science Map 2008, it becomes clear that
KAKENHI plays an important role in the diversity of Japan’s research. Adding
information about the amounts of research funding in addition to the names offunding programs, it would be possible to obtain various data regarding the effects
of research funding on the progress of scientific research by analyzing its
relationship with funding over time.
Achieving this requires information of funding data and outputs of the funding;however in Japan, KAKEN database (https://kaken.nii.ac.jp/) is the only publicly
available database that chronologically collects such information regarding funding
and its outputs. Currently, there is a time lag between the filing of reports ofresearch projects and the registration of the reports to the KAKEN database.
Furthermore, matching of papers registered in KAKEN database and records in the
Web of Science are needed. At present, it is technically difficult to put the latest
information of various research funds on the Science Map.
A method for linking funding information to the Science Map in real‐time would beto utilize the acknowledgments described in papers. Some paper databases are
beginning to record acknowledgment information for papers dating back to the late‐
2000s; however, acknowledgments are not always written in the same format andoften cannot be utilized as original expression. Standardized way to describe thefunding information in the acknowledgment should be determined in each funding
agency.
In the future, by introducing the “standardized acknowledgment codes” in all
funding agencies in Japan, similar to the patent application numbers, it should bepossible to perform real‐time monitoring of output data through paper databases.
LINKING SCIENCE AND TECHNOLOGY
The observable range of the Science Map is limited to science where research results
can be presented in the form of papers. To observe science and technology from abird’s eye view perspective, we had better to construct a technology map that cangrasp the trends of technology development through information such as patents.
By using the paper information cited in patent documentation, we could link atechnology map to the Science Map and observe the transfer of knowledge fromscience to technology and vice versa.

26

By combining this with the funding information mentioned above, we could
measure the real effects of public funding on the development of science andtechnology.
UTILIZING SCIENCE MAP AS AN ARENA FOR DISCUSSION
This report lists information, such as the number of core papers, the shares ofbenchmarking countries, and the ratio of international collaborations in each of the823 research areas on Science Map 2012; such information is to be utilized by thoseindividuals involved in Japan’s science and technology policymaking as well as the
management of Japan’s universities and public research institutions. We also
constructed the “Science Map Research Activity Sheet,” which visualizes how 153
universities and public research institutions are participating in the research areas
found on Science Map 2012.
We hope that by deepening the discussion of research management throughutilizing this kind of quantitative monitoring tool, we can increase good practices,and consequently, Japan’s universities and public research institutions willaccumulate knowledge about management at the organizational level.
When discussing research agenda setting, individual researchers and policymakers
tend to express their opinions based on their backgrounds as a member of advisoryboard. We believe that providing common information of discussion such as the
Science Map would help discussion among them with different backgrounds, where
they can utilize the map as a common basis for discussing research planning. By
sharing the same “arena,” researchers and policymakers can conduct discussions
while properly considering the distance among them. The experience of these
discussions would be beneficial for further advancement of Science Map research,thus we would be grateful to hear about practical cases on how this tool is being
utilized.

S ELECTED R EFERENCES
Börner, K., Chen, C., and Boyack, K. W. (2003), Visualizing Knowledge Domains, Annual Review of Information
Science and Technology, 37 : 179‐255.
Leydesdorff, L., and Rafols, I. (2009), A Global Map of Science Based on the ISI Subject Categories, Journal of the
Association for Information Science and Technology, 60 : 348‐362.
Saka, A., and Igami, M. (2007), Mapping Modern Science Using Co‐citation Analysis, 11th International
Conference Information Visualization (IV ʹ07), 453‐458.
Small, H. and Sweeney, E. (1985a), Clustering the Science Citation Index using Co‐citations. I. A Comparison of
Methods, Scientometrics, 7 : 391‐409.
Small, H., Sweeney, E., and Greenlee, E. (1985b), Clustering the Science Citation Index using Co‐citations. II.
Mapping Science, Scientometrics, 8 : 321‐340.

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SCIENCE MAP 2010 & 2012