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特集：ユニバーサルデザイン天文教育研究会■

Introducing Sonification asa Tool for Astrophysical Data Analysis
Wanda Diaz-Merced (Office of Astronomy for Development, South Africa / National
Society of Black Physicists, U.S.A. / Laboratory of Visual Learning, U.S.A),

Matthew Schneps (Katholieke Universiteit Leuven / University of Antwerp, Belgium),
Katrien Kolenberg (Office of Astronomy for Development, South Africa / National
Society of Black Physicists, U.S.A. / Katholieke Universiteit Leuven, Belgium),
Monika Rychtarikova (Katholieke Universiteit Leuven, Belgium),
Bert Roozen (Katholieke Universiteit Leuven, Belgium)
概要

米国マサチューセッツ州の Center forblackboard. I had never had a practicalAstrophysics（CfA）にて、天文学者・天体

experience;物理学者がデータ解析の方法について評価をastronomy of the numberless amount of行いました。フォーカスグループ研究や、ユ

satellites, I knew nothing because I hadーザビリティ研究という手法に基づく結果をnever had other experience than trying to報告いたします。視覚に加えて音を聞くといfigure out what the professor was trying toう複数の知覚を使うと、より良くデータ解析

convey in the classroom to memorize, andができる（スペクトル中に存在するシグナル

to take a test.

を見つけやすくなる）ことがわかりました。

soof

thepossibilities

inOnce I lost my sight completely and I
accepted that I had to deal with this, and1. Introduction: Background and Context

coming from visual to visual deprivation, I

Many years ago I was sighted and due tofound that I did not have access to thelongillness

deprivation.

IItransitioned
wasantovisual

undergraduatesame amount and quality of information
which

amain

streamstudentandstudent. I was at a stage, where you know

astronomer have. Although I have kept

you want to do astronomy but you have notvery

decided what you want to study. At thattechnology as we call it in the US, which isstage in my life I only knew what I learnedthein the classroom from whatever I could getaccessible, none of the up to today existent

with my residual vision from the book. I

ones provides blind people access to thewas losing my sight rapidly, experiencing

same amount and quality of information

seizures on daily basis. And when I

that a traditional scientist has. I have tried

recorded the class, on play back, it wouldeverything. I could use resignation whensound like: “if you place this term here andusing assistive tech-nology or I could saythen you substitute down here you will findinformation access empowers is a humanthe result”. To me the only thing that wasright and I want the same amount andclear was the sound of the chalk on thequality of information that a traditional

updatedtechnology

天文教育 2017 年 1 月号（Vol.29 No.1）

ontothelatest

makeassistive

information

Introducing Sonification as a Tool for Astrophysical Data Analysis－29－

astronomer has if I want to perform at

high-spatial frequency noise (overlying thetheir level.

low-spatial frequency “signal”) may act as

I began pondering to use sound to heara cognitive load that triggers mechanisms

my data. Others have done the sameof

pondering but have never materialized it.

sensitivity. Though it may be difficult to

But I would use sound without knowing if

precisely demarcate a centre to periphery

it really helps to explore this data that hasboundary,

been displayed on charts for hundreds ofdiscussion, and in accordance with theyears. My mentor and I chose to investigate

literature review, with regards to thethe hypothesis that sound as an adjunct toexperiments presented in this research we

dataincrease

took centre to periphery boundary to be atparti-cipants’ sensitivity to identify the~8° of visual angle, where changes inpresence of a simulated double-peaked

attention“black hole” pattern in simulated data,(Figure 1). The references will be available

when

upon request.

visualisation

those

will

signalsarechanging

inattention

for

that

the

response

inhibitperipheral

purposes

becomeof

thispronounced

intensity and visual field angle. We used atask

simulating

astronomers

adopt

theprocessto

searchwhich
forthecharacteristic indicators of black holes. Thetask derives from the idea that a black holeexists in the centre of each galaxy. The
molecular gas around the black hole emits
symmetric double peak spectra, which arecharacteristic with the presence of a blackhole. This signal was simulated for theFig. 1

Simulated double-peaked “blackexperiments to proof my hypothesis. Thehole” pattern signal with the noise.

experiments

Visual angles of 8°, 16° and 24° weredeterminedthesignal-to-noise ratio (S/N) thresholds atpresented to participants.

which participants could correctly identify
the presence of a simulated double-peaked“black hole” pattern which was obscured by
Gaussian noise. So the better you would

2. Implementation
Figure 1 shows the different spans used
for signal identification.

get at identifying signal in the presence ofWe are displaying the different spansnoise, the more we will hide the signal.

used for signal identification. It is theThis

participants’simulated spectra, and it is a horizontal

performance when they were experiencing

line with many little peaks or noise along it.

audio and visual presentations of that typeThis vertical noisy line raises twice in theof simulated double peak data

form of two lumps, like touching two bells.

paradigm

evaluated

In the case of this black hole task, theIf you would be touching it, it will feel like

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特集：ユニバーサルデザイン天文教育研究会■

a very hairy punk with a lots of muse thatparticipants

sometimes raises twice or remains flat. The

scientists with post-PhD publications.

werePhD-educatedspaceposition of those two lumps in ‘noise-only’
stimuli, that is, the vertical position of the3. Analysis of the Results

graph at each horizontal pixel position wasIn all the experiments participants did

determined by Gaussian noise. In ‘signal’

better when they used two modalities

stimuli, a signal consisting of two positive,(audio and visual). It means that with two

upward peaks was added to the noise.

stimuli synchronized they could identify

These peaks were modeled by identicalsignal better.

Gaussian functions with variable, but

Once we had evidence that sound as anequal, peak elevation. The quotient of peakadjunct to visual display would increase

elevation and standard deviation of thethe sensitivity of a traditional astronomer

Gaussian noise in a given stimulus wereto signal living in the data especially when

operationally defined as its signal-to-noise

the amount of noise and position of theratio (S/N). The two peaks always occurredsignal varies, I said then it is worth to try

to the left and to the right of the centre attoidentical eccentricity. The span separating

application that may help us use these

the peaks was 8° for Experiment 1 and 2

modalities to analyze and explore the data.

and 8°, 16°, or 24°, for Experiment 3. This

In order to create effective sonifications

black hole task signal gets more ambiguous

which will be usable, intuitive and usefulas the task progresses and dynamicallyto space physicists, user studies need to bechanges its intensity. This means that notundertaken to fully understand their needs

only the noise level increases but the signaland requirements and to create a prototype

strength changes dynamically.

which will not engage the space physicist

createaprototypeofcomputer

Participants were instructed to press thein data formatting as this will frustrate‘S’ button on a computer keyboard if they

them. So I carried a focus group andbelieved

usabilitythat

thecurrent

stimulus

evaluation

con-tained a signal and to press ‘N’ if they

developmentof

thethought that there was no signal. Therepreviously described.

thatleadtothexSonify prototype

was no time limit imposed on participant

As a result of the literature review, theresponses. Immediately after pressing thefocus group topic set for discussion withbutton,

participants

the volunteers centred on:

informed

whether

were

their

acoustically

responsewascorrect. We performed 3 experiments. In
eachexperimentparticipantswere

1. Data types used by space scientists.
2. The step-by-step process which spacescientists follow for data analysis, e.g.

screened for normal or corrected-to-normal

filteringvision and hearing, accurate colour vision,

selection.

normal cognitive function, and for any
history of neurological disorders. All thetechniques,

anddata

3. The user’s challenges and needs fordata analysis.

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Introducing Sonification as a Tool for Astrophysical Data Analysis
During the analysis attention was paid
tothoseissues

thatwere－31－

parameters being sought at the time. The

especiallyanalysis of the data collected from theproblematic for users when they werefocus group confirms that space physicists

performing data analysis and interacting

arewith the prototype.

analysis due to:I realized that the datasets contained1.

frustratedThe

whenforced

two main indicators pointing to theseformatting

problematic situations. For example, thearchitectures.

participant

reportedproblems:“I

performing

dataengagement

intosoftware

fit

datagot

2. The desire to analyse the data to seek

confused over the formatting of the data”.

for events which may be masked by

Also there were utterances of users, whonoise, by the current data analysis

refers to an experience using a prototype

techniques available, or by that arefrom a mission, denoting problems: “Whenaway from their direction of gaze.

analysing data from mission x, I had to100% of the participants agreed thatbuild the prototype then had to find andthere were five main stages of data

import some binaries, losing days foranalysis:
Stage 1: The first stage is visualisation ofgetting that done”.
From that we were able to identify somethe data. This visualisation is done tospot apparent signatures that may be

categories of challenges:
Unmet expectation: This refers to data
reduction and perceptualization which
the user has not been able to perform.
Data formatting strategies: This refers
to data formatting that prepares theof interest.
Stage 2: The second stage is filtering of
the data to remove noise.
Stage 3: The third stage is to correct forinstrumental effects.

data as acquired by the spacecrafts, andStage 4: The fourth step is to use

formatting to make or not, sought signal

mathematical morphology which is a

to be salient in the data.

set of filtering and segmenting tools

Informationarchitecture:Thiscate-gory refers to those elements of theinterfaces, which cause users problems.

used to visualise digital images.
Stage 5: The fifth stage is to visualise thedata again.

Perception techniques: This refers totechniques used or proposed by theparticipant to get more from their data
employing their senses.

So according to them it starts and ends
with perception of the data
During the focus group, participants said
that it was imperative for a prototype notIn

thegroup

to limit their analysis by the display, data

participants suggested to each other how totype, mathematical morphology, platform

listenandor cost. The prototype has to bring them todifferent

the correct data exploration fast andtoascertained

discussion,different
howtothefocus

data
findsets

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特集：ユニバーサルデザイン天文教育研究会■

without investing time in formatting theexplore the data in a time effective mannerdata.

and “the desire to spot signatures that areWe were very surprised!!! They wereambiguous

and/orexperiencing limitations, not to the extent I

especiallyin

do experience limitations. But I thoughtcomments included “the need to explore theperhaps I may use this for awareness. They

unexpected signal in the data before

also need user centred design!!!!

applying any filtering or mathematics”.

Thenwithallthatwebuilt

embedded

large

data

innoisesets”.

Other

the

application, taking back end and front end,

4. Conclusion

different learning styles and the needs of

By doing user centred studies we thentraditional astronomers, into consideration.

got some evidence that sensorial modalities

We ran a usability evaluation where wewill

tested:analysis, and more importantly will bringhelp

astrophysicist

inthedata

1. Understandability: Recognising theonboard other sensorial modalities andtools operability and applicability.

peoples with other coping strategies. That

2. Learnability: Attributes that bear on

universal access will benefit everyone.

theusers’ effort forlearning theSensorialmodalities

havesomuchapplication. These can be including butpotential and by applying user centred

not limited to whether the user is able

design we will be able to level the field at

to use the prototype functionalities

all skill levels for professionals, students,

unassisted, and if the user is able topeople that feel curiosity but have otherperform the exploration of the data

careers,

without investing further time in data

multimodality or user centered designformatting, or writing code. During thehasn’t been a real option for scientists

participant interaction with the data

before. It does not matter anymore because

remote data logging monitored andthis meeting has evidenced that user

recorded console output and runtime

centred design at all levels is an option so

exceptions to file.

the field will not only accommodate but

3. Operability: Is the volunteer able touse the sonification and visualisation

etc..

I

neverknew

will enhance and support the skills which
the person has to perform.

options in the tool to adjust the data tomatch their perception?
Wanda Diaz-Merced
We also monitored the user interaction
remotely,anddebriefed

why

http://www.labvislearn.org/

participants.

Participants also expressed the need to

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Introducing Sonification as a Tool for Astrophysical Data Analysis
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