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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Fuzzy cluster analysis of indicators for assessing the potential of recreational forest use</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Ivano-Frankivsk National Technical University of Oil and Gas</institution>
          ,
          <addr-line>15 Karpatska Str., Ivano-Frankivsk, 76019</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <fpage>0000</fpage>
      <lpage>0001</lpage>
      <abstract>
        <p>Cluster analysis of the efficiency of the recreational forest use of the region by separate components of the recreational forest use potential is provided in the article. The main stages of the cluster analysis of the recreational forest use level based on the predetermined components were determined. Among the agglomerative methods of cluster analysis, intended for grouping and combining the objects of study, it is common to distinguish the three most common types: the hierarchical method or the method of tree clustering; the K-means Clustering Method and the two-step aggregation method. For the correct selection of clusters, a comparative analysis of several methods was performed: arithmetic mean ranks, hierarchical methods followed by dendrogram construction, Kmeans method, which refers to reference methods, in which the number of groups is specified by the user. The cluster analysis of forestries by twenty analytical grounds was not proved by analysis of variance, so the re-clustering of certain objects was carried out according to the nine most significant analytical features. As a result, the forestry was clustered into four clusters. The conducted cluster analysis with the use of different methods allows us to state that their combination helps to select reasonable groupings, clearly illustrate the clustering procedure and rank the obtained forestry clusters.</p>
      </abstract>
      <kwd-group>
        <kwd>cluster analysis</kwd>
        <kwd>k-means clustering method</kwd>
        <kwd>forestry</kwd>
        <kwd>recreation</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>The intensive development of recreation in the world creates motivation to use
significant reserves of recreational resources. To expand the use of forest recreational
resources, it is necessary to use for this purpose not only nature reserves, but also to
involve more and more forests of state forestry farms in this use. The reserves of
recreational forest use on the territory of Ukraine are significant. Therefore, there is a
need to assess their development on the basis of the classification of forestry areas on
many analytical grounds. Taking into account the fact that such classification is a rather
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Attribution 4.0 International (CC BY 4.0).
time-consuming task, it is proposed to carry out forests clustering with the help of
software.</p>
      <p>The use of cluster analysis methods is dictated primarily by the fact that they help to
build scientifically based classifications, identify internal links between the observed
population units. In addition, cluster analysis methods can be used to compress
information, which is an important factor in the conditions of constant increase and
complication of statistical data flows. That is why this type of statistical analysis is of
great importance when analyzing the development of recreational facilities. It should
be noted that recently cluster analysis has received considerable attention from
domestic and foreign experts in various scientific fields. One of the reasons is that
modern science is increasingly relying on classification for its development. Moreover,
this process deepens as knowledge specialization grows, which in its turn is based
largely on objective classification. Another reason is related to the accompanying
deepening of specialized knowledge, the increase in the number of variables, taken into
account in the analysis of certain objects.</p>
      <p>Clustering of the studied forests will allow the effective management of recreational
areas, taking into account the reserves for improving the development of areas for
selected components and also to develop at the state level the Strategy of recreational
forest use development in Ukraine for the maintenance of the National recreational
product competitive in the domestic and world markets. Taking into consideration the
fact that each region of Ukraine is characterized by its natural and climatic conditions,
ethnic traditions and historical and cultural recreational features, there is a problem of
qualitative analysis and assessment of the level of recreational facilities development.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Background</title>
      <sec id="sec-2-1">
        <title>The foreign scientists, who studied the issue of recreational forest management, are</title>
      </sec>
      <sec id="sec-2-2">
        <title>Simon Bell [2], William M. Murphy [11], Lloyd C. Irland, Darius Adams, Ralph Alig,</title>
      </sec>
      <sec id="sec-2-3">
        <title>Carter J. Betz, Chi-Chung Chen, Mark Hutchins, Bruce A. McCarl, Ken Skog and Brent</title>
      </sec>
      <sec id="sec-2-4">
        <title>L. Sohngen [6], Nerida Anderson, Rebecca M. Ford, Lauren T. Bennett, Craig Nitschke</title>
        <p>
          and Kathryn J. H. Williams [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ], Artti Juutinen, Anna-Kaisa Kosenius and Ville
        </p>
      </sec>
      <sec id="sec-2-5">
        <title>Ovaskainen [7], Markus A. Meyer, Joachim Rathmann and Christoph Schulz [10], Tina</title>
      </sec>
      <sec id="sec-2-6">
        <title>Gerstenberg, Christoph F. Baumeister, Ulrich Schraml and Tobias Plieninger [5], Kee</title>
      </sec>
      <sec id="sec-2-7">
        <title>Cheo Lee and Kee-Rae Kang [9], Hyun-Kyu Shin and Hong-Chul Shin [12], Yevstakhii</title>
      </sec>
      <sec id="sec-2-8">
        <title>Kryzhanivskyi, Liliana Horal, Vira Shyiko, Oleksii Holubchak and Nataliia Mykytiuk</title>
        <p>
          [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ].
        </p>
        <p>Markus A. Meyer, Joachim Rathmann and Christoph Schulz proved in [10] that
visitors cluster along major paths or regions in urban and rural forest, recreation of the
local population is highly driven by relaxation, forest structures and demographic
factors play a minor role for forest benefits, forest benefits do not strongly vary within
the area of the forests, forest management should focus on avoiding nuisances to
support forest benefits. They found a weak connection between recreational behavior
and demand for specific forest characteristics. For local recreation, we recommend to
provide a basic level of highly rated FB and to avoid nuisances rather than designing
forests for a desired appearance.</p>
        <p>
          Tina Gerstenberg, Christoph F. Baumeister, Ulrich Schraml and Tobias Plieninger
in [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ] identified frequencies of activities in urban forests, visualized activity-specific
hot routes, and unveiled the contributions of landscape features to recreational use
intensity. The hot route maps represent an advancement of existing forest function
maps, as they were based on more reliable spatially explicit data on where people move
in forests. They used a public participation mapping procedure as a basis for visualizing
recreational use intensity. These maps may aid forest managers to tailor management
according to residents’ forest uses and preferences, prioritize objectives, and prevent
conflicts between re-creational user groups, conservationists and representatives of the
timber industry. They conclude that urban forest managers may promote outdoor
recreation by maintaining large proportions of broadleaved dominated stands. Finally,
accessibility to water bodies as well as unique structural compositions – as represented
by protected habitats – may enhance recreational use [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ].
        </p>
        <p>
          The purpose of Kee-Cheo Lee and Kee-Rae Kang [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ] is to classify the forests by
considering the supplier’s perspective as well as the user’s perspective in order to
provide fundamental materials for the operation of the natural recreation forests. A
factor analysis was conducted to identify the common characteristics of the selected
twelve variables by pre-selection and survey of experts. K-means cluster analysis was
conducted among those factors to classify the natural recreation forests in Korea. Four
factors were drawn after the factor analysis and the factors were named according to
the variables and sizes as ‘The use performance and visiting condition factor',
‘Education and settlement factor’, ‘Internal activation factor’ and ‘Potential factor’. In
addition, the cluster analysis of the matrix was conducted for the points of the drawn
factors and the final classification consists of five groups. The results of this study may
contribute to providing fundamental materials for the operation and management of
natural recreation forests. Also, it may act as a reference when investigating the natural
recreation forests of Korea. Proposing the classification natural recreation forests could
be helpful in selecting the proper recreation forest in the future. Based on the established
model, fundamental materials could be provided to improve the profitability of the
natural recreation forests by effectively expanding the number of tourists, creating new
natural recreation forests and proper maintenance and management [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ].
        </p>
        <p>Hyun-Kyu Shin and Hong-Chul Shin in [12] segmented recreational forest’s visitors
for marketing based on purpose of visit. Using the factor analysis, cluster analysis, cross
tab, and t-test to find out different behavioral intention in each cluster, the result elicited
some implications. First, 2 clusters were founded and has difference in behavioral
intentions. Cluster 1 (married, 200~300 hundred won income) has higher satisfaction,
revisit intention, recommendation intention. The result shows that market researcher in
recreational forest should approach different marketing strategy and has various
facilities, active program. This research needs to survey broad region to generalized
result [12].</p>
        <p>
          Thus, having considered the scientific works of both foreign and domestic
researchers of the recreational forest management problems and without diminishing
their scientific value to improve development of recreational forest management, it is
possible to consider and necessarily classify the recreational region for a component
that is its own manufacturer [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ].
3
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Methodology</title>
      <p>
        As it is known, for complex evaluation of every economic process or its components,
the methods of integrated indicators calculation are conventionally applied using
different economic and mathematical methods and approaches. The complex
evaluation is required to define the potential of recreational forest management,
considering the development of all its components. Therefore, in [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] we propose to
evaluate the potential of recreational forest use by performing the following steps: to
identify the recreational forest use potential components; to develop and form a system
of quantitative and qualitative indicators (indices) in order to evaluate the efficiency of
recreational forest use potential by its component composition; to evaluate the
efficiency of recreational forest use of the regional territories by individual components
of the recreational forest use potential using certain indicators; to comprehensively
evaluate the efficiency of each recreational forest use potential component; to conduct
an integrated evaluation of the efficiency of recreational forest use by means of using
taxonomic analysis methods and fuzzy set theory; to determine the level of the
recreational forest use potential by comparing the integrated indicator value with its
standard (critical) values [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Based on the previous studies of recreational forest
management, the following structural components of recreational forest management
potential can be formed: a resource component, social component, economic
component, innovation and investment component. Each component of recreational
forest use is characterized by a system of performance indicators. According to the
above characteristics of each component, the following system of indicators can be
proposed, considering the attributes of recreational activity, which are listed in table 1
[
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
      <sec id="sec-3-1">
        <title>Economic and mathematical modelling of evaluation of the recreational forest</title>
        <p>
          management potential determined the efficiency of recreational forest use of regional
territories by individual components of recreational forest management potential using
indicators specified in table 1. A taxonomic method based on determination of
taxonomic indicators of each component [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ] was used for this stage.
        </p>
      </sec>
      <sec id="sec-3-2">
        <title>To approve the methodology of assessing the recreational potential of forest use, a</title>
        <p>typical forestry of the Western region of Ukraine was selected, including 8 forestries.</p>
      </sec>
      <sec id="sec-3-3">
        <title>It is worth mentioning that as a result of the underdeveloped information and statistical</title>
        <p>infrastructure of forestries, it was not possible to calculate a required system of
indicators, shown in table 1. However, the taxonomic indicators were calculated based
on the actual statistical base on the resource and social components of each forestry.</p>
      </sec>
      <sec id="sec-3-4">
        <title>The calculation results of forestry activity were summarized in table 2.</title>
        <p>
          Therefore, based on obtained calculations we can conclude that recreational forest
management in Ukraine is low, confirmed by the level of recreational forest
management potential (table 2). Of 8 analysed forests only in Forestry 1 the potential
level is average, in two forestries the integrated indicator of recreational forest
management potential level has been set at a level below average, and the remaining 5
forests have a low level of recreational forest management. Graphically obtained results
are shown in figure 1 [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ].
        </p>
        <p>Indicator Substantiation</p>
        <sec id="sec-3-4-1">
          <title>Area of recreational ter- Total area of forestry intended for recreational forest</title>
          <p>ritories, km2 use</p>
        </sec>
        <sec id="sec-3-4-2">
          <title>Number of recreational Number of recreational places located on the forestry</title>
          <p>places, quantity territory intended for recreational forest management</p>
        </sec>
        <sec id="sec-3-4-3">
          <title>The level of attractive- The indicator can be evaluated according to the ness of natural and re- following criteria: exoticism, uniqueness, aesthetics, creational resources comfort, etc.</title>
        </sec>
        <sec id="sec-3-4-4">
          <title>Quality factor of forest</title>
          <p>vegetation It describes the level of recreation applicability</p>
        </sec>
        <sec id="sec-3-4-5">
          <title>Exoticism degree (cont</title>
          <p>rast) of recreational ter- It is determined as a contrast ratio degree of the resting
ritory place relative to a recreant's permanent residence</p>
        </sec>
        <sec id="sec-3-4-6">
          <title>Proportion of total forestry costs on mainte- It shows the proportion of the total costs on nance of recreational maintenance of recreational territories places, %</title>
        </sec>
        <sec id="sec-3-4-7">
          <title>Efficiency factor of re</title>
          <p>creational forest mana- It shows attractiveness of recreational forest
gement management</p>
        </sec>
        <sec id="sec-3-4-8">
          <title>Wear coefficient of recreational fixed assets It characterizes wear level of recreational fixed assets (FA)</title>
        </sec>
        <sec id="sec-3-4-9">
          <title>Volume of marginal</title>
          <p>costs for growing 1 ha They reflect the effect, achieved by improving the forest
of recreational forest as a means of labor in recreation sphere</p>
        </sec>
        <sec id="sec-3-4-10">
          <title>Capacity of a single re- It shows the maximum permissible number of persons creational load on recreational territory</title>
        </sec>
        <sec id="sec-3-4-11">
          <title>Proportion of recreant It shows a proportion of recreant employees in the total</title>
          <p>employees number of staff involved in recreational activities</p>
        </sec>
        <sec id="sec-3-4-12">
          <title>The capacity of recreation centres (resorts, tourist,</title>
          <p>health, recreational complexes) is a simultaneous</p>
        </sec>
        <sec id="sec-3-4-13">
          <title>Recreational capacity number of recreants that can be located in this centre, without disturbing ecological balance within this centre and surrounding territories</title>
        </sec>
        <sec id="sec-3-4-14">
          <title>Recreational load per 1 It determines attendance intensity for any segment of</title>
          <p>ha of forest the day, during weekends, weekdays</p>
        </sec>
        <sec id="sec-3-4-15">
          <title>The average stay of va</title>
          <p>cationers on the recrea- It shows an average length of stay of visitors on the
tional territory, h recreational territory of forest area</p>
        </sec>
        <sec id="sec-3-4-16">
          <title>Cost amount on marke</title>
          <p>ting activities of recrea- It characterizes the development level of marketing
activities
tional territories
Component Indicator Substantiation
ment compo- Efficiency of innovation
nent implementation of re- It characterizes the innovation level and efficiency of
creational forest mana- recreational innovation use
gement</p>
        </sec>
        <sec id="sec-3-4-17">
          <title>Amount of investments It shows the amount of investment resources aimed at in recreational activity recreational activities</title>
          <p>Proportion of foreign in- It shows amount of recreational activity financing at the
nvaelstamcteinvtistieisnfirneacnrceiantigo- expense of foreign financial sources</p>
        </sec>
        <sec id="sec-3-4-18">
          <title>Quantity of the won grants (programs) to fi- It characterizes relevance of the recreational sphere nance recreational acti- development vities</title>
          <p>Thus, according to the results of economic and mathematical modelling of the
integrated indicator of recreational forest management potential level, it can be
concluded that the recreational forest management potential in Ukraine is low
(figure 1), so measures should be taken to improve recreational activity results and
develop this industry. As the calculations indicate, first of all, it is urgent to develop
economic and innovation investment components of the recreational forest
management potential in Ukraine.</p>
        </sec>
      </sec>
      <sec id="sec-3-5">
        <title>Thus, having obtained the results of calculating the integrated indicator of the</title>
        <p>recreational forest use level in the studied forests, we consider it necessary to conduct
a fuzzy cluster analysis of forestry based on the analysis of forest use potential
individual indicators for the studied objects. The main stages of cluster analysis of the
recreational forest use level by predetermined components are shown in the figure 2.</p>
      </sec>
      <sec id="sec-3-6">
        <title>To implement the clustering process, it is necessary to develop a matrix of</title>
        <p>observations xij. In this case, the original set consists of m elements described by n
parameters, and each of its lines can be interpreted as a point or vector placed in
idimensional space with coordinates equal to the value of n features for a particular
forestry. Thus, in the observation matrix xij is the value of feature i for j forestry; j – a
number of classification objects (forestry); i – a number of features of the objects.</p>
        <sec id="sec-3-6-1">
          <title>Selection of indicators that are most influential in the analysis process</title>
        </sec>
        <sec id="sec-3-6-2">
          <title>Standardization of selected indicators</title>
        </sec>
        <sec id="sec-3-6-3">
          <title>Clustering of forestries using the Ward method, full connection, k-mean algorithm</title>
        </sec>
        <sec id="sec-3-6-4">
          <title>Formulation of conclusions</title>
        </sec>
      </sec>
      <sec id="sec-3-7">
        <title>Using element multiplicity w, described by n-signs, each unit can be interpreted as a point of n-dimensional space with coordinates equal to the value of n attributes for the analysed unit. Let us represent the matrix as follows:</title>
        <p>where: w is the number of study periods, n is the number of indicators of each
recreational forest management potential, xik – indicator value k of each specific
component for a year (k = 1 n, і = 1w).</p>
        <p>As indicators of recreational forest use management level assessment are reflected
in various measures, they need to be standardized. One of the most common means of
(1)
statistical generalization for inhomogeneous populations is the standardization of
indicators by the ratio of deviation (xi) to the unit of standardization. In our case, σi is
chosen as the standardization unit. These features should be normalized using the
following formula:
(2)
(3)
(4)
when</p>
        <p>=
=
∑</p>
        <p>1
 1 w  2  2
sk   w i1 (xik  xk ) 
where: zij – standardized value of indicator j for the i-th study period; xij – standardized
value of indicator j for the i-th study period; xj – arithmetic mean of kj indicator; σj –
standard deviation of k indicator; w – a number of periods.</p>
      </sec>
      <sec id="sec-3-8">
        <title>The main feature of clusters is that objects belonging to one of them are more similar</title>
        <p>to each other than objects from different clusters. Such a classification with the help of
software and computer system STATISTICA, can be performed simultaneously on a
fairly large number of analytical features. In our case, clusters will be called
geographically concentrated and interconnected by the level of recreational potential of
forestry.</p>
      </sec>
      <sec id="sec-3-9">
        <title>Among the agglomerative methods of cluster analysis, which are intended for</title>
        <p>grouping and combining objects of study, it is common to distinguish three most
common types: hierarchical method (I) or the method of tree clustering; K-means</p>
      </sec>
      <sec id="sec-3-10">
        <title>Clustering Method (II) and two-step aggregation method (III).</title>
        <p>I. Hierarchical clustering is used in the formation of clusters by determining
the distances between objects and allows you to graphically visualize the
results of the study in the form of a dendrogram. These distances can be
determined in one-dimensional or multidimensional space. However, an
important step in conducting a cluster analysis is to select the correct
method for calculating the distances between the studied objects. The main
ways to determine distances are: Euclidean distance, square of Euclidean
distances, distance of city squares (Manhattan), Chebyshev distance, power
distance.</p>
      </sec>
      <sec id="sec-3-11">
        <title>II. K-means Clustering Method is the most common among non-hierarchical</title>
        <p>methods of cluster analysis. Unlike hierarchical methods, which did not
require prior assumptions about the number of clusters, to be able to use
this method it is necessary to have a hypothesis about the most probable
number of clusters. K-means Clustering Method builds k clusters located at
as large distances from each other as possible. Note that the K-means
Clustering Method assumes that the number of clusters includes
observations with the closest average value. The method is based on
minimizing the sum of the distances squares between each observation and
the center of its cluster, i.e. the function. In this case, the choice of the
number of clusters is based on the research hypothesis. If it is not present,
it is recommended to create 2 clusters, further 3, 4, 5, comparing the
received results. The input will be Xu = {x1u, x2u,…, xmu} – a set of unmarked
data; Xkl = {x1l, x2l,…, xpl} is a set of marked data in the class k, Xl=Kk=1Xkl.
At the output, we want to obtain separated K sets {Ck} Kk = 1 of Xu, which
minimizes the objective function in k-means. Set parameters:
=
∑ ∈
(6)
1. t = 0.</p>
      </sec>
      <sec id="sec-3-12">
        <title>2. Initialization of cluster centers:</title>
        <p>=
∑ ∈</p>
      </sec>
      <sec id="sec-3-13">
        <title>3. Repeat until convergence: provide cluster data:</title>
      </sec>
      <sec id="sec-3-14">
        <title>For marked data: x  xkl provide x to the cluster Ckt+1.</title>
        <p>For unlabeled data: for xiu  xu provide to Ckt+1 a cluster obtained from
k = arg mink||xiu – μkt||2.</p>
      </sec>
      <sec id="sec-3-15">
        <title>4. Update centers:</title>
        <p>(5)
(7)
(8)
t←t+1.</p>
        <p>Another component of the algorithm is based on the discrepancy KL, which is a
measure of the mismatch between the two probability distributions. Taking into account
the K-dimensional probability vector of assignment of clusters p and q corresponding
to points respectively xp and xq, the discrepancy KL between p and q is given by the
formula:
( ‖ ) = ∑
log ,
where K is the number of clusters. In this approach, we use a symmetric variant of the
discrepancy KL, because we are dealing only with the optimization of the loss function
for p and q simultaneously:
, =
( ‖ ) +
( ‖ )</p>
      </sec>
      <sec id="sec-3-16">
        <title>Losses are obtained by first fixing p and calculating the discrepancy q with p and vice versa.</title>
      </sec>
      <sec id="sec-3-17">
        <title>The described method makes it possible to automate the process of cluster data</title>
        <p>analysis, especially if the number of clusters is unknown from the beginning. For this
purpose, the model of the neural network-based cluster data analysis system was
described on the basis of k-means and KL discrepancy methods.</p>
      </sec>
      <sec id="sec-3-18">
        <title>III. The two-way aggregation method is used in cases when you want to perform simultaneous clustering of objects (columns) and observations (rows) [11].</title>
      </sec>
      <sec id="sec-3-19">
        <title>The key to the adequacy of the economic objects cluster analysis results is a reasonable choice of factors by which the grouping is carried out. Regarding the factor characteristics, we used a four-component system of indicators, which are shown in table 1.</title>
      </sec>
      <sec id="sec-3-20">
        <title>The main purpose of cluster analysis is to break down the set of studied objects and</title>
        <p>features into homogeneous in the appropriate sense groups or clusters. This means that
the task of classifying data and identifying the appropriate structure in it is solved.</p>
      </sec>
      <sec id="sec-3-21">
        <title>Methods of cluster analysis can be used in different cases, even when it comes to a</title>
        <p>simple grouping, and which all comes down to creating groups by the number of
similarities.</p>
        <p>The need for an objective division of different economic objects into groups exists
constantly, because this classification allows you to find methods for effective
management of these objects. Methods of cluster analysis allow to solve the following
tasks: classification of objects taking into account the features that reflect the essence,
nature of objects; verification of the assumptions about the presence of some structure
in the studied set of objects, i.e. search for the existing structure; building new
classifications for phenomena that have been little studied when it is necessary to
establish the existence of relationships within the population and try to introduce a
structure into it.</p>
      </sec>
      <sec id="sec-3-22">
        <title>Cluster analysis has certain shortcomings and limitations. In particular, the</title>
        <p>composition and number of clusters depends on the selected breakdown criteria. When
reducing the original data set to a more compact form, certain distortions may occur,
and individual features of individual objects may be lost by replacing their
characteristics with generalized values of cluster parameters.</p>
      </sec>
      <sec id="sec-3-23">
        <title>When classifying objects, the possibility of the absence of any cluster values in the considered set is often ignored. In the cluster analysis it is considered that: 1) the chosen characteristics allow, in principle, a desirable division into clusters; 2) the units of measurement (scale) are chosen correctly.</title>
      </sec>
      <sec id="sec-3-24">
        <title>The quality criterion of clustering to some extent reflects the following informal</title>
        <p>requirements: 1) within groups, objects must be closely related; 2) objects of different
groups must be far from each other; 3) other things being equal, the distribution of
objects by groups must be uniform. The key point in cluster analysis is the choice of
metrics (or measures of proximity of objects), which crucially depends on the final
version of the objects division into groups with a given algorithm of division.</p>
      </sec>
      <sec id="sec-3-25">
        <title>The task of cluster analysis is to, based on the data of the set X, divide the set of</title>
        <p>objects G into m (m is an integer) of clusters (subsets) G1, G2,…, Gm, so that each object
Gj belongs to one and only one subset of the breakdown and that objects belonging to
the same cluster are similar, while objects belonging to different clusters are
heterogeneous. The solution to the problem of cluster analysis is the breakdowns that
satisfy some criterion of optimality. This criterion may be some functionality that
expresses the levels of different breakdowns desirability and groups, called the
objective function. For further research, it was possible to use the methods of theories
of complex systems and equipment made by tools used to examine the necessary
systems of complexity, which were used in conventional [4; 3; 14; 13].</p>
      </sec>
      <sec id="sec-3-26">
        <title>Let’s perform cluster analysis according to the K-means Clustering method described above for each of the selected components (table 3).</title>
        <p>Component</p>
        <sec id="sec-3-26-1">
          <title>Resource component</title>
        </sec>
        <sec id="sec-3-26-2">
          <title>Economic component</title>
        </sec>
        <sec id="sec-3-26-3">
          <title>Social component</title>
        </sec>
        <sec id="sec-3-26-4">
          <title>Innovation and investment component</title>
        </sec>
      </sec>
      <sec id="sec-3-27">
        <title>To begin with, we will standardize certain input data and summarize the results in table 4.</title>
      </sec>
      <sec id="sec-3-28">
        <title>In the first stage of the cluster analysis, we find out whether the selected objects of</title>
        <p>study (Forestris) form “natural clusters”. To do this, use the method of hierarchical
classification, in which we select the following characteristics: Amalgamation (joining)
rule: Complete Linkage, Single Linkage and Ward’s method; Distance metric is:</p>
      </sec>
      <sec id="sec-3-29">
        <title>Euclidean distances (non-standardized). The obtained clustering results are shown in figures 3-6.</title>
        <p>Tree Diagram f or 15 Cases</p>
        <p>Single Linkage
Euclidean distances
6,0
5,5
5,0
e
c
n
a
t
s
iD4,5
e
g
a
k
n
iL 4,0
3,5
3,0</p>
        <p>C_12</p>
        <p>C_10
C_15</p>
        <p>C_14</p>
        <p>C_8</p>
        <p>C_6
C_7</p>
        <p>C_5</p>
        <p>C_13</p>
        <p>C_11
C_4</p>
        <p>C_3</p>
        <p>C_2</p>
        <p>C_1
C_9</p>
      </sec>
      <sec id="sec-3-30">
        <title>Complete Linkage defines a relationship between clusters as the longest distance between two objects in different clusters (“the farthest neighbor”). Distance metric is Euclidean distances is a geometric distance in n-dimensional space and is calculated by the formula:</title>
        <p>( , ) =
∑
(
−
)
(9)</p>
      </sec>
      <sec id="sec-3-31">
        <title>From the obtained calculations and the constructed dendrogram it is possible to draw</title>
        <p>conclusions that the investigated forestries form 5 natural clusters. Let’s test the above
hypothesis by dividing the original data of K-means clustering into 5 clusters and check
the significance of the difference between the obtained groups.</p>
      </sec>
      <sec id="sec-3-32">
        <title>The best results in terms of meaningful interpretation were obtained by using an</title>
        <p>iterative method of cluster analysis, in particular the K-means clustering algorithm with
division into three clusters. After the procedures performed by using the previously
mentioned computer program, the results of clustering were obtained, which are shown
in figure 6.</p>
        <p>Tree Diagram f or 15 Cases</p>
        <p>Ward`s method
Euclidean distances</p>
        <p>C_8</p>
        <p>C_6
C_7</p>
        <p>C_5</p>
        <p>C_12</p>
        <p>C_14
C_15</p>
        <p>C_4
C_13</p>
        <p>C_10</p>
        <p>C_11</p>
        <p>C_2
C_3</p>
        <p>C_9</p>
        <p>C_1
Cluster 1
Cluster 2
Cluster 3
Cluster 4
Cluster 5
4
3
2
1
0
-1
-2
-3
-4</p>
        <p>Plot of Means for Each Cluster
Var3</p>
        <p>Var5</p>
        <p>Var7</p>
        <p>Var9</p>
        <p>Var11 Var13 Var15 Var17 Var19</p>
        <p>Variables</p>
      </sec>
      <sec id="sec-3-33">
        <title>To check the quality of the clustering, a variance analysis was performed, the results of</title>
        <p>which (table 5) indicate the relative quality of the clustering procedure: intergroup
values of variances (Between SS) do not significantly exceed intragroup values (Within</p>
      </sec>
      <sec id="sec-3-34">
        <title>SS), except for 9 factors and the level of p- significance reaches the optimal value only for 9 characteristics.</title>
      </sec>
      <sec id="sec-3-35">
        <title>Next, for qualitative clustering in the cluster analysis, we include the 9 most</title>
        <p>significant features of the previously performed analysis of variance. To implement
clustering, we use the method of hierarchical classification, in which we select the
following characteristics: Amalgamation (joining) rule: Complete Linkage, Single</p>
      </sec>
      <sec id="sec-3-36">
        <title>Linkage and Ward’s method; Distance metric is Euclidean distances (non</title>
        <p>standardized). The obtained clustering results are shown in the figures 7-9.</p>
      </sec>
      <sec id="sec-3-37">
        <title>From the obtained calculations and the constructed dendrogram we can conclude</title>
        <p>that the studied forests form 4 natural clusters. Let’s test the above hypothesis by
dividing the original data of K-means clustering into 4 clusters and check the
significance of the difference between the obtained groups.</p>
        <p>The best results in terms of meaningful interpretation were obtained by using an
iterative method of cluster analysis, in particular the K-means clustering algorithm with
division into four clusters. After the procedures performed by using the previously
mentioned computer program, the results of clustering are obtained, which are shown
in figure 10.</p>
        <p>3,4
3,2
3,0
2,8
e
c
n
tsa2,6
i
D
ge2,4
a
k
n
i
L2,2
2,0
1,8
1,6</p>
        <p>Variable
Var2
Var3
Var4
Var5
Var6
Var7
Var8
Var9
Var10
Var11
Var12
Var13
Var14
Var15
Var16
Var17
Var18
Var19
Var20
Euclidean distances
C_12</p>
        <p>C_10
C_11</p>
        <p>C_6</p>
        <p>C_15</p>
        <p>C_13
C_14</p>
        <p>C_4
C_5</p>
        <p>C_8</p>
        <p>C_7</p>
        <p>C_2
C_3</p>
        <p>C_9</p>
        <p>C_1
Fig. 7. Tree diagram for 15 forestries (Single Linkage).</p>
        <p>Tree Diagram f or 15 Cases</p>
        <p>Complete Linkage</p>
        <p>C_4
C_5</p>
        <p>C_14
C_15</p>
        <p>C_13</p>
        <p>C_8</p>
        <p>C_7</p>
        <p>C_10</p>
        <p>C_12
C_3</p>
        <p>C_2
C_11</p>
        <p>C_9</p>
        <p>C_1
2,5
2,0
1,5
1,0
0,5
0,0
-0,5
-1,0
-1,5
-2,0</p>
        <p>Plot of Means for Each Cluster
Var2</p>
        <p>Var3</p>
        <p>Var5</p>
        <p>Var7</p>
        <p>Var9 Var13 Var16 Var19 Var20
Variables
Cluster 1
Cluster 2
Cluster 3
Cluster 4</p>
        <p>Fig. 10. Average level of normed values of indicators for the selected clusters.</p>
      </sec>
      <sec id="sec-3-38">
        <title>The distance between the clusters, which are selected by K-means Clustering Method, was calculated by a simple Euclidean distance and are presented in table 6.</title>
        <p>Cluster
Number
No. 1
No. 2
No. 3
No. 4</p>
        <p>Euclidean Distances between Clusters (Апробація)
Distances below diagonal
Squared distances above diagonal</p>
        <p>No. 1 No. 2 No. 3 No. 4
0,000000 2,445802 1,394819 1,277132
1,563906 0,000000 1,068632 1,250228
1,181025 1,033747 0,000000 1,106422
1,130103 1,118136 1,051866 0,000000</p>
      </sec>
      <sec id="sec-3-39">
        <title>To check the quality of the clustering, a dispersion analysis was performed, the results</title>
        <p>of which (table 7) indicate the high quality of the clustering procedure: intergroup
values of variances (Between SS) significantly exceed intragroup values (Within SS),
and the level of p-significance is much better than the normative (0.05).</p>
        <p>Also, the contribution to the division of objects into groups is characterized by the
values of Fisher’s criterion (F-criterion) and its significance level (p): the higher the
values of the first and the smaller the values of the second, the better the clustering. For
all parameters, without exception, the significance level approaches 0, which indicates
the high statistical significance of the F-criterion. Depending on the levels of these
indicators, forestry was grouped into four clusters (table 8).</p>
      </sec>
      <sec id="sec-3-40">
        <title>For the correct selection of clusters, a comparative analysis of several methods was</title>
        <p>performed: the arithmetic mean, hierarchical methods followed by dendrogram
construction, K-means Clustering Method, which refers to reference methods in which
the number of groups is specified by the user. The cluster analysis using different
methods allows us to state that their combination helps to select reasonable groupings,
visually illustrate the clustering procedure and rank the obtained clusters.</p>
        <p>Thus, the results of the cluster analysis on 9 analytical grounds confirmed the
hypothesis of separation of 4 clusters from 15 forestries. The first cluster is formed by
five forestries 1, 2, 9, 11, 12, which are characterized by an average area of recreational
territories, biggest number of recreational sites and recreational capacity, lowest quality
factor of forest vegetation, proportion of total forestry costs on maintenance of
recreational sites, wear coefficient of recreational fixed assets, cost amount on
marketing activities of recreational territories, proportion of foreign investments in
recreational activities financing, quantity of grants (programs) won to finance
recreational activities. The second cluster is formed by three forestries 4, 5, 6. This
cluster is characterized by the highest level of recreational territories, quality factor of
forest vegetation, cost amount on marketing activities of recreational territories,
proportion of foreign investments in recreational activities financing, an average level
of recreational capacity and number of recreational sites, lowest level of proportion of
total forestry costs on maintenance of recreational sites, wear coefficient of recreational
fixed assets, quantity of grants (programs) won to finance recreational activities. The
third cluster includes four forestries 3, 7, 8, 10, which have the following
characteristics: the highest level of wear coefficient of recreational fixed assets,
recreational capacity and quantity of grants (programs) won to finance recreational
activities, average area of recreational territories, number of recreational sites and
recreational capacity, quality factor of forest vegetation, cost amount on marketing
activities of recreational territories and quantity of grants (programs) won to finance
recreational activities, lowest proportion of total forestry costs on maintenance of
recreational sites. The fourth cluster includes 3 forestries 13, 14, 15 and is characterized
by the highest level of the proportion of total forestry costs on maintenance of
recreational sites and wear coefficient of recreational fixed assets, lowest number of
recreational sites and recreational capacity, quality factor of forest vegetation,
recreational capacity, cost amount on marketing activities of recreational territories and
quantity of grants (programs) won to finance recreational activities and quantity of
grants (programs) won to finance recreational activities, the lowest of recreational sites.</p>
      </sec>
      <sec id="sec-3-41">
        <title>For the proper selection of the clusters, a comparative analysis of several methods</title>
        <p>was performed: arithmetic mean, hierarchical methods followed by dendrogram
construction, K-means method, which refers to the reference methods in which the
number of groups is specified by the user. The cluster analysis, using different methods,
allows us to state that their combination allows to select reasoned groupings, visually
illustrate the clustering procedure and rank the obtained clusters.</p>
      </sec>
      <sec id="sec-3-42">
        <title>The obtained results of clustering will help to develop separate development strategies for each isolated cluster, which will increase the efficiency of recreational areas management in the future. In addition, the results can be used to form an effective model for the development of recreational clusters.</title>
      </sec>
    </sec>
  </body>
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