4.1. Article Location on PageRank-CheiRank Plane
We first discuss some results for the local ranking indices
K and
given in
Table 3 for the 8 edition cases and the 40 edition specific selected articles. Concerning EN-Wikipedia, we note that the top 6 PageRank positions in the subset of
Table 2 are taken by religions with Catholic Church at
while the first society concept Law only appears at
. This tendency is preserved in the other 7 editions where religions still take the top 3-4 PageRank positions while such a society concept as Liberalism only appears at
for the AR, ES, FR, IT editions. There are two exceptions being Nazism at
for DE, that is clearly linked to German history, and surprisingly also for ZH where the top society concept is Law at
being significantly above Communism at
. For EN the top society concept is also Law at
and for RU it is Economy at
.
Among religions the top position is taken by Catholic Church for EN, DE, ES, IT and Christianity is at for FR, ZH (Buddhism is at for ZH). Somewhat surprisingly for RU Islam is at the top PageRank position and Christianity is at . This is probably related to a significant Muslim population in Russia that is however significantly smaller than its christian population. Islam is the top religion for the AR-Wikipedia edition which appears to be rather natural. However, here Christianity and Catholic Church appear at and respectively.
Concerning the CheiRank index
, that characterizes the communicative properties of a node, the situation is more mixed. Thus we have at
: Jainism for EN; Christianity for AR; Islam for DE, Anarchism for ES, FR; Catholic Church for IT; Monarchy for RU; Communism for ZH. We attribute such a mixing to stronger fluctuations of outgoing links as discussed in [
21].
Concerning the global ranking indices
and
for the full network, we show the density of their distribution in the
-
plane in
Figure 1 for EN, AR, DE, ES and
Figure 2 for FR, IT, RU, ZH. The overall density structure is rather comparable for all 8 editions with a certain asymmetry between both axis. However, the precise top
and
positions (isolated small red or green squares) are very specific for each edition.
Furthermore, the locations of the 40 edition specific selected articles of
Table 2 and
Table 3 are also shown in
Figure 1 and
Figure 2. We see that for all editions religion nodes (white crosses corresponding to
) have typically higher PageRank positions (lower
values) as compared to social concepts (red crosses corresponding to
), i. e. typically the top religion nodes appear to be more important than the top society nodes. In particular, for the EN-edition the top religion PageRank index is about 6 times smaller as compared to the top social concept PageRank index as can be seen from
Table 2. For the other editions, we have similar ratios of
between the top religion and the top society nodes which can be seen from the difference of the horizontal positions between the first white cross and the first red cross (difference of
) in the different panels of
Figure 1 and
Figure 2.
4.2. Matrix Components of REGOMAX Algorithm
We have computed the different reduced Google matrix components (as described in
Section 3.3) for the 8 Wikipedia edition and using for each edition the edition specific group of 40 articles given in
Table 2 and
Table 3 (as explained in
Section 2.2). The presentation order of the nodes in the groups is given by the index
which was obtained by separately PageRank ordering the 23 nodes for society concepts and the 17 nodes for religions (or branches of religions) for the EN-Wikipedia edition. However, for the other editions there are different
K and
indices but for practical reasons we keep the same initial node order
(obtained from EN-Wikipedia) when presenting the different matrix components in the figures below.
We remind that
is according to (
4) given by the sum
where
represents the direct links,
indirect links with
being a rank-1 matrix (with columns being rather close to the projected PageRank
) taking into account the contributions of the leading eigenvector in the complementary scattering space (see [
22] for details) and
is obtained from the other contributions and containing interesting nontrivial information about indirect links. Numerically,
is quite dominant in this sum with relative weights
-
depending on the edition but it has a very simple structure. The interesting properties of the reduced Google matrix are contained in the matrix
being the sum of
and
(with diagonal elements of the latter replaced by 0). For two editions (EN and ZH), we present results for the four matrices
,
,
and
while for the other six editions we limit ourselves to
and
.
Below we will focus our discussion on the most interesting case . To simplify this discussion, we also introduce for this matrix the sub-blocks A (left top diagonal society block), B (right top block with links from religion to society), C (left bottom block with links from society to religion) and D (bottom right diagonal religion block). In particular, we determine the strongest matrix element for each block, the sum of matrix elements per block and the ratios , , for these sums. In the next subsection, we will see that the matrix can also be exploited to generate effective networks of friends and followers.
In
Figure 3, we show color density plots for
,
,
and
for the edition EN with numerical weights being
,
,
,
(
). The color plot of
is essentially composed of rows of equal color with matrix elements
for all columns
j. Here the sequence of row colors illustrates the separate PageRange order in the two blocks. The row with red color corresponds to the top PageRank node “Catholic Church” with
,
, first row in the religion block, and the rows below at
with orange or (strong) green color correspond to
. The color plot of
is similar in appearance, due to the strong weight of
, but with additional peaks at isolated positions with largest elements of
or
(including some quite strong diagonal elements of
, especially in the religion block).
For the strongest matrix elements for each block A, B, C and D (for links ) correspond to: 0.0126 (Education ← Oligarchy, A); 0.0021 (Economy ← Chinese folk religion, B); 0.0125 (Shia Islam ← Oligarchy, C); 0.0172 (Islam ← Sunni Islam, D). The last value appears as a sum of a direct link and also a stronger indirect link from Sunni Islam to Islam while the two links from Oligarchy to Education or Shia Islam result from direct links also clearly visible in .
We also observe that the two diagonal blocks
A and
D seem rather decoupled with significantly smaller links in the off-diagonal blocks
B and
C which is also confirmed by the sum ratios
,
,
. The value of
is above to the ratio of areas
showing that the transitions inside the religion block
D are more intense comparing to the society concepts block
A, this difference is also related to the particularly strong maximal element in the
D block (see above). The decoupling between the two blocks, which is also be confirmed for the other 7 Wikipedia editions discussed below, seems to be surprising in view of the important historical role played by religions in society formation. However, on the other side there is a well known statement from the Bible:
Render unto Caesar the things that are Caesar’s, and unto God the things that are God’s (Bible Matthew 22:21 [
35]) that may be partially at the origin of this result. Also in certain countries, e.g. France, the separation between the state and religions is fixed by law.
Figure 4 shows the matrices
and
for the two editions
and
. For AR we have the weights
with higher weights of
and
as compared to EN. For AR the strongest matrix elements of
per block correspond to: 0.1067 (Monarchy ← Autocracy,
A); 0.0063 (Law ← Catholic Church,
B); 0.0132 (Islam ← Law,
C); 0.0524 (Taoism ← Confucianism,
D). The first element of this list is related to the fact that several islamic countries are monarchies. The sum ratios are
,
,
. Here in the panel of
one sees a strong red row at
for the top PageRank node Islam.
In a similar way, we obtain for DE and here the strongest matrix elements of per block correspond to: 0.0327 (Democracy ← Oligarchy, A); 0.0137 (Communism ← Chinese folk religion, B); 0.0058 (Islam ← Republic, C); 0.0209 (Hinduism ← Jainism, D). The sum ratios are , , . As for EN there is a red row for at for Catholic Church.
For the ES edition (top panels of
Figure 5) we find
,
,
and the strongest matrix elements of
per block correspond to: 0.0222 (Oligarchy ← Autocracy,
A); 0.0117 (Society ← Confucianism,
B); 0.0082 (Buddhism ← Materialism,
C); 0.0346 (Islam ← Sunni Islam,
D). Here we have in the
D block a second very strong matrix element with value 0.0296 (Islam ← Shia Islam). The sum ratios are given by
,
,
. As for EN and DE there is a red row for
at
for Catholic Church.
For FR (bottom panels of
Figure 5) we have
,
,
and the strongest matrix elements of
per block correspond to: 0.0222 (Culture ← Society,
A); 0.0101 (Politics ← Confucianism,
B); 0.0178 (Christianity ← Autocracy,
C); 0.0198 (Buddhism ← Chinese folk religion,
D) with additional strong matrix elements 0.0191 (Capitalism ← Economy,
A), 0.0179 (Education ← Economy,
A), 0.0176 (Communism ← Economy,
A), 0.0189 (Taoism ← Chinese folk religion,
B) and 0.0170 (Monarchy ← Autocracy,
A). We attribute the last link and the top
C link from Autocracy to Christianity to the
baptême de Clovis when the king of France Clovis I accepted the Christian religion around the year 500. The sum ratios are
,
,
. There is a red row for
at
,
for Christianity along with strong orange rows at
,
(Islam) and
,
(Catholic Church).
For the IT edition (top panels of
Figure 6) the matrix weights are
,
,
and the strongest matrix elements of
per block correspond to: 0.0298 (Economy ← Society,
A); 0.0108 (Democracy ← Sunni Islam,
B); 0.0095 (Christianity ← Idealism,
C); 0.0326 (Islam ← Shia Islam,
D). Furthermore there are significant numbers of additional strong matrix elements in the
D-block: 0.0313 (Taoism ← Chinese folk religion); 0.0307 (Islam ← Sunni Islam); 0.0285 (Confucianism ← Chinese folk religion); 0.0260 (Shinto ← Chinese folk religion) and also in the
A-block: 0.0292 (Democracy ← Autocracy); 0.0280 (Fascism ← Autocracy); 0.0278 (Monarchy ← Autocracy); 0.0273 (Oligarchy ← Autocracy); 0.0272 (Culture ← Society); 0.0266 (Republic ← Autocracy), the latter probably being related to Italian history. The sum ratios are given by
,
,
and there are two strongs rows for
being red (
,
, Catholic Church) and orange (
,
, Christianity).
For RU (bottom panels of
Figure 6) we have
,
,
and the strongest matrix elements of
per block correspond to: 0.0223 (Materialism ← Idealism,
A); 0.0043 (Capitalism ← Protestantism,
B); 0.0066 (Buddhism ← Civilization,
C); 0.0569 (Taoism ← Chinese folk religion,
D). Here we have the sum ratios
,
,
and in the
panel we see two orange-red rows at
,
(Islam) and, with slightly smaller values, at
,
(Christianity).
Finally, in
Figure 7 we show the matrices for
,
,
and
of the ZH edition. Here the weights are:
(
). For ZH the strongest matrix elements of
per block correspond to: 0.0341 (Fascism ← Nazism,
A); 0.0097 (Education ← Judaism,
B); 0.0219 (Christianity ← Idealism,
C); 0.0653 (Christianity ← Oriental Orthodox Churches,
D) and the block-sum ratios are
,
,
. In the panel of
we see a strong red row at
,
(Christianity), which appears less pronounced (between orange and strong green) in the other panel of
but mainly because the very strong maximal direct matrix element in the
D-block of
(and of
corresponding to the link Christianity ← Oriental Orthodox Churches) shifts the maximum value in the color plot defining the red color which reduces the color scale of other matrix elements. We note that the structure of the matrix
follows for ZH mainly
for the strongest transitions.
The results of this subsection show that for the matrices of all 8 editions there are indeed multiple significant transitions inside both blocks of society concepts and of religions. However, the transitions between these two blocks are, roughly by a factor 5-10, smaller if we compare the sums of matrix elements of the off-diagonal block to the sums over the diagonal blocks. The ratio of transition strengths of the two diagonal blocks is typically somewhat larger than the ratio of block areas . This shows that transitions between religions are on average a bit stronger than those between society concepts.
4.3. Network Structure Inside Social Concepts and Religions
In this section, we present effective network diagrams for friends and followers based on the information contained in the matrix
or more precisely in its two diagonal blocks
A for society concepts and
D for religions. Since, according to the results of the last subsection, these two blocks are rather well decoupled with only weak links between them, we will present separate network diagrams for each block. Network diagrams of (nearly) the same style, were for example used in [
22] (for groups of political leaders in the Wikipedia network), [
25] (for banks and countries in the Wikipedia network), and [
27] (for a specific fibrosis related protein group in the MetaCore network of proteins).
However, for convenience, we present here the construction method of these network diagrams. Assume we have a small matrix g with elements being either a reduced Google matrix or one of its components (e.g. , , or ) or a certain sub-block of such a matrix (e.g. society or religion sub-blocks A or D of shown in the previous section). First, we choose in the list of nodes (associated to this matrix or block) 5 top nodes representing five different subgroups based on some categorization criteria (depending on the set of nodes and the context) and we attribute each other node of this list to exactly one of the 5 subgroups (based on some criteria and the context). In the following, we will use for these subgroups the notation poles as a synomym for “center of interest” which is a typical use of this expression in the French language. For each pole, we also define some presentation color.
To construct the effective friend network (see below for the other case of follower networks), we draw first a main circle (thin gray line) and place the 5 top nodes uniformly on this circle with some label and the corresponding color. Then we select for each top node j (also called level-1 nodes) the four strongest friends i (level-2 nodes) with strongest outgoing links , i. e. with largest matrix elements in the same column j of this matrix. Each of these strongest friends, if not yet present in the diagram as another level-1 node, is placed on a smaller secondary circle around the top level-1 node associated to him and we draw thick black arrows from the level-1 nodes to their friends. It is possible that a new level-2 node appears as a friend of several initial level-1 nodes. In this case, we try first to place this level-2 node on the circle of the level-1 node with same color (same pole) if possible, i. e. if this level-2 node is indeed a friend of the level-1 node of same color. Only if this is not possible, we place it on the circle of another level-1 node (first level-1 node of different color which has the given level-2 node as friend). If a level-1 node has a friend which is already present in the diagram as another level-1 node, we simply draw a thick black arrow from the former to the latter and do not modify the position of the latter.
The procedure is repeated for all (newly added) level-2 nodes with smaller circles around them on which we place their (up to) four strongest friends (level-3 nodes if newly added) and with the same rule for preferential placement on a circle of a parent node of same color. Now, we draw thin red arrows from the level-2 nodes to their friends. In case if such a friend is already present in the network (as level-1 or level-2 node), his position is not modified and we only draw the thin red arrow from his parent node to him. We also mention that only non-empty circles with at least one node on them are drawn; i. e. if a given node has no newly added friends (i. e. all his friend are already in the diagram), then we will not draw an empty circle around him.
At this stage, we typically stop the procedure for simplicity. Even if we continue this procedure with level-4, level-5 nodes etc. the number of newly added nodes quickly decreases and when there is no newly added node the procedure converges to a stable final diagram. This can happen actually quite early so that their is typically no big difference in diagrams limited to level-3 nodes and those with higher level nodes. In particular, for the diagrams given below, the number of newly added level-3 nodes is typically already quite small (much smaller than the theoretical limit ) also because the available set of nodes is limited from the very beginning, even significantly smaller than the theoretical level-3 limit. In some of the diagrams below there are even no newly added level-3 nodes (if absence of smallest level-3 circles) and we have already convergence to a stable diagram at level-2, i. e. all friends of level-2 nodes are already present in the diagram as former level-1 or level-2 nodes. In case of convergence, the last stage does not add new nodes but it still adds arrows from the most recently added nodes in the previous stage to their friends (which are already present in the network diagram).
The construction of follower network diagrams is essentially the same with two modifications: (i) at each level k we select for each level-k node i (typically only in our case) the four strongest followers j (as possible level- node if not yet present in the diagram) with strongest incoming links defined by the largest matrix elements in the same row i; (ii) arrows (thick black or thin red) are drawn with inverted directions from followers (level- nodes) to parents (level-k nodes), e.g. there are some arrows from a circle node to its center node while in the friend diagrams we have arrows from the circle center to the outside nodes on the circle (note in case of multiple parent nodes or pre-existing friends or followers, we have typically a significant number of other type of arrows between different circles).
In this work, we present figures for the network diagrams constructed from the two diagonal blocks
A for society related nodes and
D for religions of the matrix
for the 8 different Wikipedia editions. Since there are two friend and follower diagrams for each case, we have per edition four network diagrams presented in a figure with four panels. The subgroups or poles together with their respective 5 top nodes for both society and religion cases are given in
Table 2 (8th column) and this table also contains a two letter code for each node (5 th column) used as a node label in the diagrams.
For society concepts, we choose the 5 top pole nodes Law, Society, Communism, Liberalism and Capitalism with respective node colors being olive, (dark) green, cyan, blue and indigo. We have tried to attribute the members of the poles based on the context and logical proximity to the top node, e.g. Education and Culture are attributed to the 2nd pole of Society; Ecology, Politics belong to the first pole of Law; Socialism and Anarchism are attributed to the 3rd pole for Communism. In certain cases, this attribution is a bit arbitrary and other choices would have been possible. We also tried to assure that each pole has a certain minimum number of members.
For the religion nodes, we choose the 5 top pole religions Christianity, Islam, Buddhism, Hinduism and Chinese folk religion (same colors as for the society top nodes in this order) and with its pole members being related to branches of religions or sub-religions. Here, we have attributed Judaism to the 1st Christianity pole with other members being Catholic Church, Protestantism and both nodes about Orthodox Church.
In the following, we will more precisely call this poles also “initial poles” in order to distinguish them from “natural poles” which may emerge naturally by certain clusters in a network diagram. Quite often natural poles and initial poles are very similar but in certain cases natural poles are composed of nodes from several initial poles.
Specifically, for the EN edition, whose network diagrams are shown in
Figure 8, we can identify in the friend society diagram the formation of 5 natural poles (which may slightly deviate from the initial poles) with main members being 1T) Law, Politics, Monarchy, Autocracy (2 initial poles); 2T) Society, Culture, Education (1 initial pole); 3T) Communism, Socialism, Anarchism, Nazism, Fascism (2 initial poles); 4T) Liberalism, Democracy, Republic (1 initial pole) and 5T) Capitalism, Money, Economy (1 initial pole). Thus the natural pole Communism has the largest number of diagram members even if it is composed of nodes belonging to two different initial poles.
The diagram of followers has the natural poles 1T) Law, Politics, Monarchy (2 initial poles); 2T) Society, Culture, Education, Civilization, Oligarchy (1 initial pol); 3T) Communism, Socialism, Fascism, Nazism, Autocracy, Idealism (5 initial poles); 4T) Liberalism, Democracy, Republic, Anarchism (2 initial pol); 5T) Capitalism, Money, Economy (1 initial pol). Thus again the strongest natural pole is formed around Communism.
For the diagram of religion friends we have from
Figure 8 the natural pole members: 1T) Christianity, Catholic Church, Eastern Orthodox Church, Judaism, Protestantism, Oriental Orthodox Churches (1 initial pol); 2T) Islam, Sunni Islam, Shia Islam (1 initial pol); 3T) Buddhism, Taoism (1 initial pol); 4T) Hinduism, Jainism, Sikhism (1 initial pol); 5T) Chinese folk religion, Confucianism (2 initial poles). The strongest pole is Christianity, however, it is somehow isolated having strong links only from Islam while the poles of Islam, Buddhism, Hinduism, Chinese folk religion have more active interconnections.
For the diagram of religion followers we find: 1T) Christianity, Eastern Orthodox Church, Protestantism, Oriental Orthodox Churches, Catholic Church (1 initial pole); 2T) Islam, Sunni Islam, Shia Islam (1 initial pole); 3T) Buddhism, Taoism (1 initial pole); 4T) Hinduism, Jainism, Sikhism (1 initial pole); 5T) Chinese folk religion, Confucianism, Shinto (2 initial poles). Here the strongest pole is again Christianity, and now it is less isolated with connections to Islam and Chinese folk religion. At the same time we see here more intense links between religions from Asia (3T, 4T, 5T) forming a strongly interconnected religion group.
The diagram of friends for society concepts of AR, whose network diagrams are shown
Figure 9, has a reduced number of nodes as compared to EN in
Figure 8, but the poles are more interconnected by strong links. Interestingly, the Communism pole does not include Fascism, Nazism in contrast to the EN edition. For the diagram of society followers the natural pole with largest number of nodes is Law with 7 members and 4 initial poles, The Communism pole includes only Socialism and Anarchism in contrast to EN where the (natural) pole of Capitalism also includes Fascism and Nazism.
For the AR diagram of friends for religions in
Figure 9, we see that the Christianity pole contains a larger number of members as in the EN case but there are more links between poles and the Christianity pole is not as isolated as it is for EN. However, for the diagram of followers the Christianity pole remains more isolated compared to the EN, also there are no strong black links between Christianity and Islam.
For the DE edition the diagrams are presented in
Figure 10. For the diagram of friends for society concepts the strongest natural pole is Liberalism with Democracy, Fascism, Nazism, Monarchy and Oligarchy (3 initial poles) while for EN Fascism and Nazism are included in the Communism pole; also for DE the poles are more densely interconnected as compared to EN. For the diagram of followers, we again see a significant difference with EN, thus Fascism and Nazism are included in Liberalism pole while they are in the Communism pole for EN.
For the DE religion diagrams we have denser interconnections between the 5 poles as compared to EN. In the case of followers there are no strong links between Islam and Christianity but there are many (level-2) red links between their respective pole members.
For the ES edition the network diagrams are given in
Figure 11. Its society friend diagram is similar to EN but there are less nodes in the Liberalism pole (i. e. the direct friends of Liberalism are the other four level-1 top nodes), also Fascism and Nazism are absent. For the case of followers there are less pole members for Society, Communism but more for Law and Liberalism; Nazism is attributed to the Liberalism pole, Nazism is absent which is different from the EN case.
For the religion diagrams of ES in
Figure 11 the case of friends is similar to those of the EN edition but there are less links between the Islam and Christianity poles.
For the FR edition the network diagrams are shown in
Figure 12. Here the society friend diagram is similar to the case of EN but with less links between the Society and Liberalism poles; as for EN the nodes Nazism and Fascism belong to the Communism natural pole. For the case of followers the Communism pole has only one node Nazism (from another initial pole) while for EN this pole contains 6 members including Fascism and Nazism. The religion diagrams of FR are quite similar with those of EN.
The network diagrams for the IT edition are presented in
Figure 13. For the society friend diagram the largest pole is Society including Culture, Education, Civilization, Oligarchy and Monarchy (all nodes from the same initial pole); the Liberalism pole includes Democracy and Fascism while Communism has only Socialism that makes the last two poles rather different from the EN edition; the Capitalism pole is the same as for EN case; the Law pole contains only Politics and Republic. For the society follower network of IT the highest number of members is in the pole of Communism including Socialism, Materialism, Idealism, Civilization and Monarchy (3 initial poles). In both society friend and follower diagrams, thoe node Fascism is attributed to Liberalism and while Nazism is absent which constitutes a drastic difference with the EN case.
In the religion friend diagram of IT the node Christianity has the highest number of nodes and it is strongly linked with Islam, Buddhism and Hinduism in contrast to EN where this pole is more isolated. The diagram of followers is similar to those of the EN edition and Christianity remains the strongest pole.
In
Figure 14 we show the network diagrams for the RU edition. Here the society friend diagram is similar to EN but without Fascism, Nazism in the diagram, also poles Law and Society have a bit less of included nodes. In the diagram of followers Fascism and Nazism are included in the Liberalism pole in contrast to the EN edition where these 2 nodes are included in Communism pole.
For the religion friend diagram Christianity has the largest number of nodes including Judaism linked also from Islam and this pole is less isolates as in the EN edition. For the diagram of religion followers Christianity is still the largest pole with 6 nodes including Judaism pointing to Islam but in other aspects this diagram is similar to the EN edition.
Finally, for the edition ZH the diagrams are presented in
Figure 15. In the society friend diagram the strongest pole is Law including Politics, Civilization, Autocracy, Monarchy, Economy and surprisingly Fascism. We note that for ZH the node Law has the unusual local Rank value
for a society node which are normally well behind the religion nodes in PageRank order. The Communism pole includes only Socialism being well linked to the Society pole, in contrast to the EN case; Liberalism and Capitalism poles are similar to EN. In the society followers diagram the strongest pole is again Law with 6 nodes and 3 initial poles; Fascism and Nazism are included in the Liberalism pole.
For the religion friend diagram of ZH the strongest pole is Christianity with 6 nodes being well connected to other poles, in contrast to the EN case; at the same time the interlinks between Asian religion poles Buddhism, Hinduism, Chinese folk religion are denser as compared to EN. In the religion follower diagram the strongest pole is also Christianity with 6 nodes, the diagram structure is similar to EN with a larger number of links between Islam and Hinduism poles.
4.4. Proximity and Differences of Cultures
Let us summarize the most important differences and similarities between the 8 cultures represented by the 8 language Wikipedia editions obtained in the last subsection by analyzing the different network diagrams.
First for the society diagrams the English and French cultures attribute the two nodes Fascism and Nazism to the Communism pole while they are attributed to the Capitalism pole by the Arabic culture and to the Liberalism pole by the German, Spanish (partially), Italian (partially), Russian (for followers) and Chinese (for followers) cultures.
Concerning the religion diagrams, the Christianity pole seems to be rather isolated in the English culture with other links only from the Islam pole (in the friend diagram). On the other hand, for the other cultures the Christianity pole is well connected not only with the Islam pole but also with the other poles of Hinduism, Buddhism and Chinese folk religion. For a majority of cultures the three poles of the above Asian religions have a higher density of links between them as compared to the Islam and Christianity poles.
To determine quantitatively the proximity of the 8 cultures, we compute the correlators for certain key quantities shown in
Figure 16. The 6 panels of
Figure 16 provide
-matrix density plots for different inter edition correlators with 5 panels for the Pearson correlator of 5 quantities being the matrix
, the (group local) PageRank vector
, the religion and society sub-blocks for
and the local PageRank index
K and one additional panel for the Kendall correlator of
K. The precise definitions of these correlator quantities with some additional technical details are given in Sub
Section 3.4 and we note that for such correlator quantities the minimal mathematical possible value is
, for the case of two data sets with strong anti-correlations, while values close to 0 indicate weak or absent correlations and values close to
correspond to strong correlations.
First, we observe that generally all 8 Wikipedia edition seem to be rather well correlated with a big majority of correlator values being above 0.5 and only a few values close to 0.33. The two correlators associated to
and
(top row of
Figure 16) are very close which is plausible due to the typical strong numerical weight of
in
and the fact that the columns of
are close to
. Here the correlations of DE between AR, RU and ZH seem minimal (still with values
) and also ZH seems to be less correlated to the other editions (with some fluctuations). The other inter edition correlations are typically quite strong
with the largest values
-
for the correlation between ES and IT.
More specifically, for the -correlator and EN the closest other editions are FR (0.882) and ES (0.858); for AR the largest values are with RU (0.896) and FR (0.867) which appears to be plausible due to the, at least partial, importance of Islam in these three cultures. For DE the two closest cultures are ES (0.845) and IT (0.803); for ES they are IT (0.933) and EN 0.858); for FR they are RU (0.885) EN (0.882); for IT they are ES (0.933) and FR (0.842); for RU they are AR (0.896) and FR(0.885) and finally for ZH they are FR (0.774) and RU (0.767). For the very similar -correlator this list of closest two editions is identical with only slightly different correlator values.
Concerning the religion block of
(center left panel of
Figure 16), we see that AR and ZH have globally the weakest correlations to the other cultures, with values
, which seems natural due to the importance of their specific religions. On the other hand here, we have a block of four strongly correlated editions EN, DE, ES, FR between them, with values
, while IT and RU have typical “intermediate” correlations
.
More explicitly, for this case the closest cultures of EN are ES (0.892) and DE (0.844); for AR they are FR (0.699) and ES (0.662) with relatively low values; for DE they are EN (0.844), FR (0.814) and ES (0.806); for ES they are EN (0.892), FR (0.814) and DE (0.806); for FR they are DE (0.814), ES (0.814) and EN (0.801); for IT they are ES (0.76) and EN (0.746); for RU they are DE (0.737) and EN (0.73) and finally the strongest correlator of ZH is to EN (0.694).
The society block of
(center right panel of
Figure 16) shows the “weakest” general correlations of all correlator quantities with (off-diagonal) values being typically
with the strongest off-diagonal element being 0.565 between DE and ZH which is due to two strong matrix elements in
due to the links from Oligarchy to Democracy and Monarchy for both editions. Here the AR-RU correlator represents the minimal correlator value
for all editions and all correlator quantities.
The Pearson and Kendall correlator of the PageRank index
K (bottom row of
Figure 16) appear to have roughly a similar relative structure as the Pearson correlators of
and
(top row of
Figure 16). However, here the overall values are significantly stronger (lower) for the Pearson (Kendall)
K-correlator in comparison to the top row values. For the Kendall correlator of
K and the two editions EN and ZN there is an additional suppression of the correlator values to other editions which are mostly close to
. Furthermore, for both
K-correlators, we have a block of 5 editions DE, ES, FR, IT and RU of relatively strong correlations between them and AR has somewhat intermediate correlations to this block while EN and ZH seem to be a bit more separated from this block (but still with significant correlator values).