1、2“ I CAL REPORT ETR 113 October 1993 Source: ETSI TC-HF Reference: DTR/HF-O1 O1 OC UDC: 621.39 Key words: Usability evaluation, controls and indicators, pictograms, icons, symbols Human Factors (HF); Results of an evaluation study of pictograms for point-to-point videotelephony ETSI European Telecom
2、munications Standards Institute ETSI Secretariat Postal address: 06921 Sophia Antipolis Cedex - FRANCE Office address: Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE Tel.: +33 92 94 42 O0 - Fax: +33 93 65 47 16 European Telecommunications Standards Institute 1 993. All rights reserved. No
3、 part may be reproduced except as authorised by written permission. The copyright and the foregoing restriction on reproduction extend to all media in which the information may be embodied. 3404583 0098433 304 0 Page 2 ETR 113:1993 Whilst every care has been taken in the preparation and publication
4、of this document, errors in content, typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to “ETSI Editing and Standards Approval Dept.“ at the address shown on the title page. Page 3 ETR 113:1993 Contents Foreword . 5 1 2 3 4 5 6 7 8 9 10 Scope . 7 Refer
5、ences . 7 Abbreviations . 7 General . 8 4.1 Methodological considerations . 8 The ETSI evaluation study of pictograms for point-to-point videophone functions . 9 5.1 The pre-test 9 5.2 The main evaluation study . 9 5.3 Partners taking part in the study . 9 5.4 The post-test . 10 Method . 10 6.1 Mate
6、rial 1 : the pictogram families tested in the study 10 6.2 Material 2: the questionnaire 10 6.3 The respondents 12 6.4 Procedure . 13 Results 13 7.1 Effects of order and learning 13 7.2 The results for Task 1 (Test of Associativeness) . 14 7.2.1 Task 1 : Pictogram selection 14 7.2.2 Task 1 : Subject
7、ive certainty and representativeness . 18 Part 2: Test of pictogram preference . 19 Task 3: Overall family preference . 19 7.3 7.4 Discussion of the results 20 8.1 Results on the level of the pictogram Family 20 8.2 Results on the level of individual pictograms 21 The recommendation of pictograms fo
8、r point-to-point videotelephony . 24 The post-test . 25 1 O . 1 Rationale . 25 10.2 Method . 25 10.3 Results . 25 10.3.1 The results for Task 1 (Test of Associativeness) 25 10.3.2 Pictogram selection . 25 10.3.3 Subjective Certainty and Representativeness . 27 10.3.4 Part 2: Test of Pictogram prefer
9、ence 28 10.3.5 Task 3: Overall Family preference 28 Discussion of the results . 28 Confirmation of the Multiple Index Approach 29 10.4 10.5 Annex A (informative): The seven pictogram families tested in the main study . 30 Annex B (informative): Results of the total sample (n = 687) 33 Annex C (infor
10、mative): Tables with the results of the main study (summary) . 38 M 3404583 0098433 I187 Page 4 ETR 113:1993 Annex D (informative): Example sections of the questionnaire 40 Annex E (informative): The three pictogram families tested in the post-test 51 Annex F (informative): Results of the post-test
11、sample (n = 62) . Task 1 : Selection Matrices . 52 Annex G (informative): Results of the post-test . summary 54 Annex H (informative): Acknowledgements . 55 History . 57 = 3404583 O098434 013 Page 5 ETR 113:1993 Foreword This ETSI Technical Report (ETR) has been produced by the Human Factors (HF) Te
12、chnical Committee of the European Telecommunications Standards Institute (ETSI). ETRs are informative documents resulting from ETSI studies which are not appropriate for European Telecommunication Standard (ETSI or Interim European Telecommunication Standard (I-ETS) status. An ETR may be used to pub
13、lish material which is either of an informative nature, relating to the use or the application of ETSs or I-ETSs, or which is immature and not yet suitable for formal adoption as an ETS or an I-ETS. H 3404583 0078435 T5T I Page 7 ETR 113:1993 1 Scope This ETSI Technical Report (ETR) gives the result
14、s of an evaluation study of pictograms for basic videotelephony functions. The seven functions covered by the study are: a) b) c) d) e) f) g) VIDEOPHONE / TELEPHONE (upgrading / downgrading the call); CAMERA ON / OFF (turning on and off picture transmission); MICROPHONE ON / OFF (turning on and off
15、sound transmission); SELFVIEW (turning on and off the selfview function); STILL PICTURE (turning on and off screen freeze); DOCUMENT CAMERA (switching between document and person cameras); and HANDSFREE (switching between handset and handsfree modes). Seven pictogram sets, each containing candidate
16、pictograms for the seven basic videophone functions, were empirically evaluated with the aim of identifying the most suitable pictogram set. Data for this study were collected in eight European countries from more than 650 respondents. The results of the study lead to the recommendation of a combine
17、d set of pictograms. The Multiple Index Approach to the evaluation of pictograms is described in detail in ETR 070 ill. The seven recommended pictograms are the content of ETS 300 375 21. 2 References For the purpose of this ETR the following references apply. 21 31 ETR 070 (1 993): “Human Factors (
18、HF); The Multiple Index Approach (MIA) for the evaluation of pictograms“. ETS 300 375: “Human Factors (HF); Pictograms for point-to-point videophony“ . 41 7-IEC-5467: “Graphical symbols for use on equipment. Index, survey and compilation of single sheets“. 3 Abbreviations For the purposes of this ET
19、R, the following abbreviations apply: DIN Deutsches Institut fr Normung EC European Commission ETR ETSI Technical Report ETC European Telecommunication Standard ETSI European Telecommunications Standards Institute HF Human Factors I-ETS Interim European Telecommunication Standard IEC International E
20、lectrotechnical Commission PSN People with Special Needs Previous page is blank 3404583 0098436 996 Page 8 ETR 113:1993 4 General Pictograms and icons1) have the potential of easing the use of telecommunications devices. Well designed pictograms allow the user to intuitively understand which functio
21、n the pictogram represents. In addition, they are said to require less learning time and effort than text based alternatives. They are “international“ in the sense that they are not bound to a particular language and can be understood by illiterate people as well. Standardized pictograms for basic v
22、ideophone functions allow the user to recognise the basic functions of any videophone without the need for extra instruction. However, international empirical tests are necessary to verify that pictograms carry the same intuitive meaning in different cultures and language communities. 4.1 Methodolog
23、ical considerations Before comparing different methodologicai options available for testing pictograms, we have to establish by which criteria the pictograms will be judged, or in other words, what establishes a good set of pictograms*. From what has been said before, a set of pictograms is consider
24、ed a good set if: - - - each of its elements is associated with the corresponding referent (.e. the function to be represented); none of its elements is associated with any referent other than the corresponding one; users feel subjectively certain in their selection of a pictogram (.e. in the select
25、ion of a control to use to bring about a desired effect). Therefore, the testing method has to focus on correct associations as well as on errors and it has to take into account the respondents subjective certainty. In addition, the most realistic evaluation approach is one that tries to represent a
26、n actual usage situation, .e. a recognition situation in which a user with a certain intention (e.9. switching on the self-view function of a videophone) is confronted with the controls of a device and needs to make a choice as to which control will bring about the desired effect. There are basicall
27、y four ways of assessing the associativeness of pictograms: Display Task Set of pictograms and one referent. One pictogram and the list of referents. Set of pictograms and list of referents. 1) One pictogram at a time. Name referent. 2) 3) 4) Pick pictogram that represents the referent. Pick the ref
28、erent that is represented by the pictogram. To map the elements of each list. The four options meet the criteria specified above to different degrees. The first test is one of recall rather than recognition processes. The third one, in which all referents and only one pictogram are presented at a ti
29、me, is equally badly suited for the present aim since in a real-life situation, the user of a videophone may have all pictograms visually present but sIhe will not necessarily have a complete cognitive representation of all functions of the terminal as defined by the referents. The same applies to O
30、ption 4) which has the additional disadvantage that it is a one-to-one mapping and that certain errors (like one pictogram being associated with two referents) do not occur. Some recommendations suggest combinations of the three options mentioned so far. Option 21, .e. the test in which the complete
31、 set of pictograms is presented to the subject (as would be in the case of a real videophone call situation in which the pictograms are placed on the terminal) and only one referent is presented at a time, was the testing method used for this ETR. In addition to its greater validity, it possessed th
32、e advantage of allowing all four kinds of outcomes of a signal detection situation (Hit, Miss, False Alarm and Correct Rejection) thus making a more detailed analysis possible. In this document, the term “pictogram“ is used for the graphical representation of a function or an element of a user inter
33、face. In this sense it is equivalent to the term “icon“. In the following, it is assumed that a set of pictograms is to be tested that represents a number of functions of a device as opposed to single, stand alone pictograms. 2, 3404583 0098437 822 Page 9 ETR 113:1993 The Multiple Index Approach, as
34、 described in ETR 070 111, was developed on the basis of these considerations. The approach used in this ETR takes the form of a questionnaire with three parts (it is, of course, possible to implement the test on computers with sufficiently high resolution screens): - in Part 1 of the questionnaire,
35、 one referent (name and description of a function) at a time is presented with all pictograms of one set (Test of pictogram acsociativenessl. The respondents task is to choose the appropriate pictogram for the function in question. In addition, subjective certainty and suitability ratings are requir
36、ed for each pictogram; - in Part 2, the respondent is asked to give preference ratings on the level of functions (Test of pictogram preference), .e. all candidates for one function are shown and the most suitable one is supposed to be indicated; - in Part 3, preference ratings are requested on the l
37、evel of sets (Test of family preference), .e. all sets are displayed and the preferred one is supposed to be indicated. The results of the Test of pictogram associativeness are the main indicator for the usability of the sets to be tested. The Tests of pictogram and family preference are to be used
38、mainly to verify that a pictogram set fulfils not only the associativeness criterion but also aesthetic criteria. Furthermore, they can be used in cases in which there are competing sets with similar results for associativeness. Finally, order and learning effects should be controlled for by employi
39、ng versions of the questionnaire with a different presentation order of the pictograms. 5 The ETSI evaluation study of pictograms for point-to-point videophone functions 5.1 The pre-test To test the suitability of the approach outlined in Clause 4, a detailed evaluation method, the Multiple Index Ap
40、proach, was designed and tested on a small sample of subjects using eight pictogram sets. The results of this test of the eight pictogram sets and of the evaluation methodology itself confirmed the suitability of the Multiple Index Approach. 5.2 The main evaluation study Based on the results of the
41、pre-test, seven of the eight pictogram sets used in the pre-test (one set was withdrawn by the designers) were tested in the main evaluation study with the aim of identifying the most suitable pictogram set according to the specified criteria. The seven basic videophone functions for which pictogram
42、s were designed and tested are as follows: a) b) c) d) e) f) 9) VIDEOPHONE / TELEPHONE (upgrading / downgrading the call); CAMERA ON / OFF (turning on and off picture transmission); MICROPHONE ON / OFF (turning on and off sound transmission); SELFVIEW ON / OFF (turning on and off the selfview functi
43、on); STILL PICTURE ON / OFF (turning on and off screen freeze); DOCUMENT CAMERA ON / OFF (switching between document and person cameras); HANDSFREE ON / OFF (switching between handset and handsfree modes). The testing method of the proposed pictogram sets is one of a paper and pencil test. The quest
44、ionnaire is described in detail in Clause 6. 5.3 Partners taking part in the study The intention was to collect data in as many ETSI member countries as possible in order to enhance the representativeness of the study and to spread the burden of data collection to several partners. Running the quest
45、ionnaire in as many languages as possible has the additional beneficial effect of lowering the risk of including language-bound or culture-bound pictograms. 3404583 0098438 769 E Page 10 ETR 113:1993 The following institutions took part in the study: Norwegian Telecom Ericsson Frystyk Consult ApS Da
46、nish Centre of Technology for Disabled Persons HUSAT Research Institute Heinrich-Hertz-Institut Berlin Aro-Club of the EC Telefnica hVeStigaCi6n y Desarrollo Fundazione UQO Bordini CSELT Foundation of Research and Technology Heraklion SEL-AG Stuttgart Norway Sweden Denmark Denmark Great Britain Germ
47、any Germany European Community Spain Italy Italy Greece These 12 institutions from eight countries cover a large area of the European continent excluding only the group of Eastern European countries. 5.4 The post-test As the results of the main study led to a recommendation of a mixed set, a “post-t
48、est“ was conducted with subjects from Berlin and Madrid. This post-test and the results obtained are described in Clause 10. 6 Method 6.1 Material 1 : the pictogram families tested in the study Seven pictogram sets (or “families“), each with pictograms for the seven videophone functions considered i
49、n the evaluation study, were tested. The designers of the seven families were: 1) 2) CSELT Torino, Italy; 3) 4) 5) 6) 7) Deutsches Institut fr Normung e.V.(DIN), Berlin, Fed. Rep. Germany; Philips Corporate Industrial Design, Eindhoven, The Netherlands; Teledirektoratets forskningsavdeling (Norwegian Telecom Research Dept) ., Kjeller, Norway; SEL - AG, Forschungszentrum Stuttgart, Stuttgart, Fed. Rep. Germany; Ferris Associates - User Interface Designers, Bishops Stortford, Great Britain; Telefnica - Investigacin y Desarrollo, Madrid, Spain. The seven pictogram families ar
