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Visual Programming Pdf 189591 | Inve Mem 2018 302890

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                          Visual Programming Languages for Programmers 
                                                       with Dyslexia: an Experiment 
                                    Jose L. Fuertes                                       Luis F. Gonzalez                                         Lo,c Martinez 
                       Departamento de Lenguajes y Sistemas                     Universidad Politecnica de Madrid                   Departamento de Lenguajes y Sistemas 
                       Informaticos e Ingenieria de Software              Politecnico Colombiano Jaime Isaza Cadavid                 Informaticos e Ingenieria de Software 
                         Universidad Politecnica de Madrid                              Medellin, Colombia                             Universidad Politecnica de Madrid 
                                     Madrid, Spain                                   lfgonzaleza@elpoli.edu.co                                     Madrid, Spain 
                                  jfuertes@fi.upm.es                                                                                              loic@fi.upm.es 
                       Abstract-A survey  of  351  programmers,  including  people                         There are statistical data to show that 12.4% of a group of 
                   with  dyslexia,  has  found  that  programmers with  dyslexia  are                  computer programmers state that they believe that they have 
                   33.4%  more  productive  if  they  use  a  visual  programming 
                                                                                                       dyslexia  [3].  On  this  ground,  one  member  of  a  team  of 
                   language. This paper presents important aspects of the profile of 
                                                                                                       programmers may very well have symptoms of dyslexia. This 
                   programmers with dyslexia, introduces the most commonly used 
                                                                                                       may  have  a  bearing  on  the  expected  results  of  the  group. 
                   textual    programming  languages  (TPL)  by  a  group  of 
                                                                                                      However, there is no proposal to help programmers with and 
                   programmers,         classifies    the    31    most  common  visual 
                                                                                                       without  dyslexia  to  interact  in  a  team  development 
                   programming languages (VPL) for the study group, and analyzes 
                                                                                                       environment. 
                   some technical and facilitation features to support the needs of 
                   programmers with dyslexia, in five of these languages that have                         This paper is part of a PhD research project whose goal is 
                   been considered  current  and  relevant for  the purposes of  this                  to define an interaction model for computer programmers that 
                   research.  The  visual  programming  language  Alice  has  been 
                                                                                                       would be beneficial for programmers with dyslexia and that 
                   selected  as  the  language  to  be  included  in  a  comparison 
                                                                                                       would enable them to participate in development teams. This 
                   experiment with the Java programming language. Results of the 
                                                                                                       model would be an important contribution to this area, making 
                   experiment  establish  preferences  and  levels  of  effectiveness  of 
                                                                                                       a  positive  impact on software development. This would result 
                   Alice against the other language, according to the performance of 
                                                                                                       in greater efficiency and reduced development times for a team 
                   a group of programmers who participated in the experiment. 
                                                                                                       of programmers with dyslexic members. 
                                                                                                           To desi       the  proposed  model,  different  tasks have been 
                                                                                                                     gn 
                                                                                                       carried out which are presented in this work and which were 
                                                                                                       necessary  to  identify  the  visual programming  language with 
                                               I.  INTRODUCTION 
                                                                                                       which programmers with dyslexia interact best. 
                        Studies conducted by Rello and Baeza-Yates [l] claim that 
                   the  percentage  of  the  population  admitting  to  having                             This paper starts by giving an account the major emotional, 
                   dyslexia  has  grown  considerably  since  Steve  Jobs  publicly                    behavioral,  physical  and  programming-related characteristics 
                   confessed  that  he  suffered  from  the  effects of this  learning                 identified  in  programmers  with  dyslexia  during  software 
                   disorder. In fact, many people who had not been diagnosed                           development  [ 4]. It  also  establishes the relationship  of these 
                   as having the disability or were not receiving treatment for the                    characteristics  with  specific  VPL  elements.  It then  reports  a 
                   disorder  have  come  forward,  and  some  have  even  sought                       preliminary classification  of the  VPLs that  the  programmers 
                   professional  help.  However,  dyslexia  in  adults  tends  to  be                  that  took  the  survey  identified  as  being  the  most  popular 
                   disregarded, because they  learn  to  live  with the  disorder  and                 according to their purpose, relevance and applicability. It then 
                   break  off  professional  treatment,  without  realizing  that  this                describes  an  analysis  of  the  main  technical  and  other 
                   functional  diversity  can  affect  their  communication  with                      facilitation features for programmers with dyslexia, of the five 
                   other  people  or  their  job  performance.                                         languages identified as possible benchmarks for the selection 
                                                                                                       of  the  ideal  VPL  to  include  in  a  comparison  experiment 
                        Studies in computer science, and particularly  programming, 
                                                                                                       between programmers with and without dyslexia, to measure 
                   have  found  that  dyslexia  has  an  impact  and  has  been  a 
                                                                                                       the level  of  satisfaction  and efficiency in the  use of a visual 
                   barrier  limiting  the  efficiency  of  software  development 
                                                                                                      programming language versus a textual programming language 
                   processes. As  far  as  we  know,  there  has  been  no  other 
                                                                                                       and  justify  the  desi       of  the  proposed  model.  Finally,  the 
                                                                                                                                gn 
                   research  to  date  focusing  on  specifically  helping  computer 
                                                                                                       details and results of the experiment are presented. 
                   programmers with dyslexia.  However,  there  are  studies  [2] 
                   corroborating  the  wide-ranging  problems  that  people  with 
                                                                                                                         II.  MATERIALS AND METHODS 
                   dyslexia  have  with  computer  use,  concluding  that  students 
                   from this  population  group working with programming tools 
                                                                                                           This research started with a review of the existing scientific 
                   with  visual  or  graphic  aids            are    more  successful  at 
                                                                                                       literature to identify the characteristics of adults with dyslexia. 
                   developing  and  understanding  computer  programs  than 
                                                                                                      Based  on  the  identified  characteristics  we  developed  a 
                   programmers without dyslexia. 
                                                                                                       quantitative      cross-sectional       study      in    351      computer 
                 pro ammers, chosen using double sampling (at convenience                  with    dyslexia.    However,  it       was  established       which 
                     gr
                 and discretionary snowball), to  obtain  a map of needs, skills           characteristics play a role in defining this profile[6]. 
                 and characteristics of pro    ammers with dyslexia. This allowed 
                                             gr
                                                                                               1)    Behavioral variables: The results yielded by previous
                 us to define the profile of pro      ammers with dyslexia and to 
                                                   gr
                                                                                           research reveal that pro     ammers with dyslexia have different 
                 determine  their  specifics  needs  to  work  with  a  language                                     gr
                                                                                           emotional and behavioral traits than other pro         ammers. The 
                 pro amming.  Some  results  of  the  previous  study,  together                                                               gr
                     gr
                 with the literature review, allowed the identification of the 31          most si    ificant are related to: 
                                                                                                   gn
                 visual pro    amming languages most used by the respondents. 
                            gr                                                                 •    Anxiety:  40.4% of pro      ammers with dyslexia suffer
                                                                                                                              gr
                 These languages  were  classified  according  to their  purpose, 
                                                                                                    from higher levels of anxiety when pro       amming.
                                                                                                                                               gr
                 validity and relevance, resulting in 5 languages to be included 
                                                                                               •    Concentration:  pro ammer  concentration  rates  are
                 in  future  studies.  With  these,  we  carry  out  a  descriptive                                       gr
                 analysis    of   the   technical    characteristics   and    another               generally high when pro amming.
                                                                                                                               gr
                 observational  analysis  of  some  nontechnical  characteristics 
                                                                                               •    Distraction:  despite  the  above  finding,  pro    ammers
                                                                                                                                                      gr
                 related to the profile defined in the previous point was carried 
                                                                                                    with  dyslexia  tend  to  get  easily  distracted  when
                 out,  which can be considered as facilitators for pro        ammers 
                                                                           gr
                                                                                                    studying.
                 with dyslexia. The study allowed  for the establishment  of a 
                 VPL that in the future could become ideal to help minimize the                •
                                                                                                    Depression: rates of depression do not tend to be high
                 effects  of dyslexia. in a    oup of pro ammers working as a 
                                             gr             gr                                      among pro ammers with dyslexia.
                                                                                                                gr
                 team. 
                                                                                               •    Retiring:    unlike    other    people     with    dyslexia,
                     In a third phase, a classification and analysis of the most 
                                                                                                    pro ammers with dyslexia are not withdrawn and are
                                                                                                        gr
                 commonly used textual pro amming languages by the                oup 
                                                gr                              gr                  able to easily socialize with other people.
                 of pro    ammers was  performed.  Objet and  frequency  of use 
                        gr
                                                                                               •    Loss  of  focus:  pro    ammers  with  dyslexia  may  be
                 were  analyzed,  and  this  led  to  the  selection  of  Java  as  the                                   gr
                                                                                                    easily sidetracked if there is too much information on
                 language to be included in future experiments. 
                                                                                                    screen when they are performing pro        amming tasks.
                                                                                                                                            gr
                     In the final phase, an experimental observational study was 
                                                                                               •    Inconspicuousness: pro      ammers with dyslexia do not
                 carried  out  on  the  use  of  Java  and  Alice  pro amming                                                 gr
                                                                           gr
                                                                                                    usually like to draw attention to themselves.
                 languages. 39 computer pro       ammers participated, 15 of whom 
                                               gr
                 claimed to have dyslexia symptoms. 
                                                                                               •    Conscientiousness:  pro ammers  with  dyslexia  are
                                                                                                                               gr
                                                                                                    very conscientious.
                     III. ANALYSIS OF PROGRAMMERS WITH DYSLEXIA AND 
                                                                                               •    Ag essiveness:  pro ammers  with  dyslexia  are
                                    PROGRAMMING LANGUAGES                                               gr                  gr
                                                                                                    relatively serene people and are not ag     essive.
                                                                                                                                              gr
                 A.   Profile of Programmers with Dyslexia
                                                                                               •
                                                                                                    On the other hand, the major findings for pro       ammers
                                                                                                                                                      gr
                     An information gathering method was applied to a sample                        with  dyslexia  can  be  said  to  be  related  to  certain
                 of  315  Spanish-speaking  pro       ammers  [4].  12.4%  of  all                  physical  behaviors  that  may  or  may  not  affect  their
                                                    gr
                                                                   = 
                 respondents believed that they are dyslexic (n       39). The above                pro amming  performance.  The  most si           ificant  are
                                                                                                        gr                                        gn
                 survey researched variables divided into three       oups:                         related to:
                                                                    gr
                     •    Demo aphic variables. The following variables were                   •
                                                                                                    Transposition of letters when reading or writing: this is
                                 gr
                          analyzed in this area: sex, age, and nationality.                         the  most  common  behavior  and  very  patent  when
                                                                                                    working with a text-based pro      amming language.
                                                                                                                                     gr
                     •    Behavioral  variables.  The  following            oups  of
                                                                          gr
                          variables  were  analyzed  in  this  area:  emotions,                •    Short-term  memory  impairment:  this  shows  up  as
                          behavior, and physical traits.                                            having to continuously reread recently written code.
                     •    Pro amming variables. The following variables were                   •
                                                                                                    Insomnia:  adults  with  dyslexia  usually  have  trouble
                              gr
                          analyzed in this area:  usability  problems, preferences                  sleeping,  but  this  is  not  a  common  trait  among the
                          for different pro   amming languages.                                     surveyed dyslexic pro     ammers.
                                           gr                                                                               gr
                     The  most  recurrent  characteristics  among  pro        ammers           •
                                                                           gr                       Visual  stress:  pro    ammers  with  dyslexia  have  a
                                                                                                                          gr
                 with  dyslexia were identified and  they  were  found to  make 
                                                                                                    serious problem with screens full of text and interfaces
                 fewer  mistakes  when  working  with  a  visual  pro amming 
                                                                           gr                       with some back ound and font colors, font sizes and
                                                                                                                      gr
                 language. In addition, 33.4% were better able to develop and 
                                                                                                    character  and  line  spacing  as  they  easily  get
                 understand  visual  pro    ams  than  pro    ammers that  did  not 
                                          gr                gr                                      sidetracked and lose interest in the job they are doing.
                 have symptoms of dyslexia, thereby confirming the hypothesis 
                                                                                               2)    Programming-Related          Variables:    Alsobhi      and
                 stated  by  Dixon  [2].  By  synthesizing  the  characteristics 
                                                                                           Abeysinghe [7] claim that dyslexia is associated with a normal 
                 identified  by  the  study  within  this  population    oup,  it  was 
                                                                       gr
                 concluded that not all the emotional, behavioral and physical             or above average intellectual coefficient and that people with 
                 traits of adults with dyslexia reported by other researchers [5]          this functional diversity are usually better software developers 
                 had a bearing on the definition of the profile of the pro     ammer 
                                                                            gr             than  regular  people.  However,  it  was  found  that  there  are 
                skills,  behaviors  and difficulties  that may or  may  not affect          •    Applicability:  the  language  to  be  selected  has  to  be
                their  performance  in  programming-related  tasks.  The  most                   currently  applicable  for  use  in  practice.  Possible
                                                                                                 values: Yes, No.
                si   ificant are: 
                  gn
                    •    Analytical  skill:  Alsobhi  and  Abeysinghe's  findings           Table II shows the preliminary classification according to 
                         were  confirmed,  especially  with  respect  to  the           the above  variables based on the information gathered about 
                         analytical skill.                                              the 31 languages. 
                    •    Problem  identification:  despite  the  above  finding,            After  this  preliminary  analysis,  the  classification  was 
                         20.0% of programmers with dyslexia were found to               summarized as shown in Table III. We originally intended to 
                         have trouble performing this task.                             consider  only  general-purpose  languages  for  the  subsequent 
                                                                                        study,  as  the  aim  was  to  preselect  a  language  capable  of 
                    •    Command use and specific syntax handling: 20.3% of
                                                                                        performing complex programming tasks. However, since some 
                         programmers  with  dyslexia  stated  that  they  find
                                                                                        special-purpose  programming  languages  were  found  to  be 
                         specific text-based programming language commands
                                                                                        relevant,  popular  and  have  important  features,  the  most 
                         and syntax confusing to use.
                                                                                        si   ificant ones were considered. 
                                                                                          gn
                                                                                            Although  Blackly,  Stencyl,  Code  and  Subtext  are  tools 
                B.   Selection of Textual Programming Language
                                                                                        highly  relevant,  they  were not selected because they are not 
                    51 textual programming languages were identified as being
                                                                                        regarded as programming languages as such or run as a web 
                 commonly  used  by  the  351  programmers  surveyed.  A  first 
                                                                                        page. 
                 classification  was  made  to  determine  the  language  to  be 
                 included  in  subsequent  studies.  The  variables  Purpose  and 
                                                                                            TABLE II.  CLASSIFICATION OF VISUAL PROGRAMMING LANGUAGES 
                Frequency helped to make this classification: 
                    •    Purpose: To classify language in general or specific.
                                                                                                                             Analyzed Variables 
                                                                                           Visual Programming 
                    •    Frequency:  number of participants in the survey that
                                                                                                Language 
                         have used the language.                                                                  Purpose     Validity     Applicability 
                    Table I shows the use frequency and percentage of the 9 
                                                                                          Alice [8]               Special    Yes        Yes 
                most used textual programming languages. 
                                                                                          Appinventor [9]         General    Yes        Yes 
                                                                                          Ark [10]                Special    No         No 
                    After  classifying  and  analyzing  9  textual  programming 
                                                                                          Blockly [ 11]           Special    Yes        No 
                languages identified as the most used by 3 51  programmers, it 
                was determined that  Java  would be the ideal  language to be             Code [12]               General    Yes        No 
                included in our model desi     .                                          Cube [10]               Special    No         No 
                                            gn
                                                                                          Drakon [13]             Special    No         No 
                C.   Analysis of Visual Programming Languages                             Fabric [14]             Special    Yes        No 
                                                                                          Forms/3 [10]            General    No         No 
                    The  selected  3 1  visual  programming  languages  were
                                                                                          G [15]                  Special    Yes        No 
                provisionally classified according to the following variables to 
                                                                                          GameSalad [16]          Special    Yes        No 
                determine the languages to be included in later analyses: 
                                                                                          Max [17]                Special    Yes        No 
                    •    Purpose: whether the language has general or specific
                                                                                          Netlogo [15]            Special    Yes        No 
                         purpose.
                                                                                          Nxt-g [18]              Special    No         No 
                    •    Validity:  this  variable  was  selected as  there  may  be      Kodu [19]               Special    Yes        Yes 
                         some  special-purpose  programming  languages  that              Lava [20]               General    No         No 
                         may  warrant  inclusion  in  the  final  study.  Possible        Limnor [21]             General    No         No 
                         values: Yes, No.                                                 Prograph [10]           General    No         No 
                                                                                          Pure data [22]          Special    Yes        No 
                                                                                          Quartz Composer [23]    Special    Yes        No 
                    TABLE I. USE FREQUENCY OF TEXTUAL PROGRAMMING LANGUAGES 
                                                                                          Robolab [24]            Special    Yes        No 
                        Textual Programming 
                                                                                          Scratch [25].           Special    Yes        Yes 
                                                    Frequency      Percentage 
                             Languages 
                                                                                          Simulink [12]           Special    Yes        No 
                   Java                            293          83.48 
                                                                                          Snap! [26]              General    Yes        Yes 
                   C                               229          65.24 
                                                                                          Stencyl [27]            Special    Yes        No 
                   JavaScript                       161         45.87 
                                                                                          Subtext [28]            General    Yes        No 
                   C++                             149          42.45 
                                                                                          Toontalk [29]           General    No         No 
                   Python                          134          38.18 
                                                                                          Vee [30]                Special    Yes        No 
                   PHP                              114         32.48 
                                                                                          Vipr [10]               General    No         No 
                   C#                              102          29.06 
                                                                                          Vissim [31]             Special    Yes        No 
                   Visual .Net                      80          22.79 
                                                                                          vvvv [32]               Special    Yes        No 
                   M(MATLAB)                        16           4.56 
                       Note that the Drakon language is not considered applicable                        •   Type  systems:  data  typing  is  closely  related  to  the
                   because  it  is  related  to  a  Russian  project,  and  all  the                         program runtime. There is a lot of debate whether static
                  documentation that we have found is in Russian.                                            or  dynamic  type  systems  are  more  efficient  [33].
                                                                                                             Possible values: static (S), dynamic (D), static-dynamic
                       In total, we selected five VPLs: two were general-purpose, 
                                                                                                             (SD).
                   applicable  and  relevant  languages  (Appinventor  and  Snap!) 
                                                                                                         •   Concurrent  programming:  this refers  to  programming
                   and  three  were  special-purpose,  applicable  and  relevant 
                                                                                                             notations     and     techniques      to    express      potential
                   languages (Alice, Kodu and Scratch). 
                                                                                                             parallelism  and  solve  problems  more  efficiently  [34].
                       Table III present a summa         of the prima      classification of 
                                                      ry                ry                                   Possible  values:  concurrent  programming  is  enabled
                  visual programs languages. 
                                                                                                             (Yes), concurrent programming is not enabled (No).
                       After  selecting  the  VPLs,  we  analyzed  some  of  the                         •   Procedural  abstraction:  this  refers  to  whether  the
                  technical and facilitative characteristics for programmers with                            language  can  decompose  the  program  into  modules,
                   dyslexia. They are described below.                                                       functions or subprograms.  Possible values:  procedural
                                                                                                             abstraction is enabled (Yes),  procedural abstraction is
                       1)  Technical         Characteristics:          The         following 
                                                                                                             not enabled (No).
                   characteristics  were  selected  for  inclusion  in  the  final 
                                                                                                         •
                                                                                                             Data  abstraction:        this    refers    to    whether  the
                   classification  because they  are  highly  relevant to  the future 
                                                                                                             programming technique can be used to invent or define
                   research to be developed: 
                                                                                                             new data types (user-defined data types) adapted to the
                       •    Implementation language:  this characteristic refers to
                                                                                                             application  to  be  implemented  [35].  Possible  values:
                            the  language(s)  in  which  the  VPL  was  developed.
                                                                                                             data abstraction is enabled (Yes), data abstraction is not
                            Possible values: Java (J), Microsoft XNA (X), Kawa
                                                                                                             enabled (No).
                            (K), Squek (S).
                                                                                                         •   Other  language:  The  visual  programming  language
                       •    Operating  system:  this  characteristic  refers  to  the
                                                                                                             allows  to generate an equivalent code in a text-based
                            operating  systems  on  which  the  language  runs.
                                                                                                             language  or metalanguage,  either directly  or  through
                            Possible  values:  Windows  (W),  MacOS  (M),  Linux
                                                                                                             external processes. Possible values: Java directly (J _ D),
                            (L), Android (A), Xbox 360 (X).
                                                                                                             XML directly (XML_ D), XML by external conversion
                       •   Flow  control:  the  effectiveness  of  a  programming
                                                                                                             (XML_ E), does not allow conversion (NP).
                           language largely depends on whether the runtime flow
                                                                                                        2) Facilitative characteristics of the visual programming
                           can be changed by means of control structures:  close
                                                                                                    language for programmers with dyslexia: Based on the profile 
                           screen (C _ S),  close  screen with result (C _ SR), count
                                                                                                    of  programmers  with  dyslexia,  we  identified  some  VPL 
                           (C), do (DO), do in order (D _ 0), do together (D _ T),
                                                                                                    characteristics that may help to  improve the performance of 
                           each in together (E _ IT), for (F), for each (F _ E), for each
                                                                                                    programmers  when working with  any  of these  languages. 
                           in (F _ EI), forever (F _ E), for range (F _ R), get start text
                                                                                                    They  have  been  grouped  into  three  categories  which  are 
                           (G _ ST),  if (I),  if then  else  (I_ TE),  repeat  (R),  repeat
                           until (R _ U), when (W _ H), while (W).                                  described below. 
                       •                                                                                 a) Characteristics related to the transposition of  letters
                           License type: with a view to future project development
                           decisions, it is important to determine whether the VPL                  when  reading  or  writing:  VPLs  convey  information  more 
                           has an open or  closed  source license.  Possible values:                visually than text-based languages [36]. However, text is still 
                           open source license (0), closed source license (C).                      a feature of many VPLs, and there are three key issues related 
                                                                                                    to its use that warrant analysis: 
                       •   Visual building method: the building method refers to
                           how the program is created.  Possible  values:  simple                        •    Nodes: it is important to analyze whether moving the
                           drag  and  drop  (DD)  when  there  are several types  of                          mouse over or seconda           clicking on onscreen nodes
                                                                                                                                          ry 
                           notchless blocks that the user drags and drops to create                           or  elements  delivers  information.  Possible  values:
                           the code; puzzle drag and drop (PDD), where most of                                detailed information on all nodes and elements (DT),
                           the blocks have notches and have to fit perfectly like the                         detailed  information  on  some  nodes  and  elements
                           pieces of a jigsaw; visual (V), when there is a set of                             (DA),  basic  information  on  all  nodes  and  elements
                           icons governing specific program construction tasks.                               (BT), basic information on some nodes and elements
                                                                                                              (BA), a combination of basic and detailed information
                                                                                                              (CD), no information on nodes and elements (ND).
                               TABLE III.  SUMMARY OF THE VPL CLASSIFICATION 
                                           Classification                     Number                     •    Identifier names:  this  characteristic  refers to how the
                         Nonapplicable special-purpose VPLs                       4                           VPL  manages  variable  names,  constants,  types,
                                                                                                              subprograms.  Possible  values:  user  can  define
                          Irrelevant special-purpose VPLs                        15 
                                                                                                              identifier  names  (Y),  user  cannot  define  identifier
                          Applicable and relevant special-purpose VPLs            3 
                                                                                                              names (N).
                         Nonapplicable general-purpose VPLs                       5 
                                                                                                         •    Expressions:  this  characteristic  refers  to  aspects  like
                          Irrelevant general-purpose VPLs                         2 
                                                                                                              the  definition  and  use  of  mathematical  formulae.
                          Applicable and relevant general-purpose VPLs            2                           Possible     values:    there     are   icons     for   creating
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...Visual programming languages for programmers with dyslexia an experiment jose l fuertes luis f gonzalez lo c martinez departamento de lenguajes y sistemas universidad politecnica madrid informaticos e ingenieria software politecnico colombiano jaime isaza cadavid medellin colombia spain lfgonzaleza elpoli edu co jfuertes fi upm es loic abstract a survey of including people there are statistical data to show that group has found computer state they believe have more productive if use on this ground one member team language paper presents important aspects the profile may very well symptoms introduces most commonly used bearing expected results textual tpl by however is no proposal help and classifies common without interact in development vpl study analyzes environment some technical facilitation features support needs five these part phd research project whose goal been considered current relevant purposes define interaction model alice would be beneficial selected as included comparis...

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