?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Target+Acquisition+in+Multiscale+Electronic+Worlds&rft.creator=Guiard%2C+Yves&rft.creator=Beaudouin-Lafon%2C+Michel&rft.subject=Human+Computer+Interaction&rft.description=Since+the+advent+of+graphical+user+interfaces%2C+electronic+information+has+grown+exponentially%2C+whereas+the+size+of+screen+displays+has+stayed+almost+the+same.+Multiscale+interfaces+were+designed+to+address+this+mismatch%2C+allowing+users+to+adjust+the+scale+at+which+they+interact+with+information+objects.+Although+the+technology+has+progressed+quickly%2C+the+theory+has+lagged+behind.+Multiscale+interfaces+pose+a+stimulating+theoretical+challenge%2C+reformulating+the+classic+target-acquisition+problem+from+the+physical+world+into+an+infinitely+rescalable+electronic+world.+We+address+this+challenge+by+extending+Fitts%E2%80%99+original+pointing+paradigm%3A+we+introduce+the+scale+variable%2C+thus+defining+a+multiscale+pointing+paradigm.+This+article+reports+on+our+theoretical+and+empirical+results.+We+show+that+target-acquisition+performance+in+a+zooming+interface+must+obey+Fitts%E2%80%99+law%2C+and+more+specifically%2C+that+target-acquisition+time+must+be+proportional+to+the+index+of+difficulty.+Moreover%2C+we+complement+Fitts%E2%80%99+law+by+accounting+for+the+effect+of+view+size+on+pointing+performance%2C+showing+that+performance+bandwidth+is+proportional+to+view+size%2C+up+to+a+ceiling+effect.+The+first+empirical+study+shows+that+Fitts%E2%80%99+law+does+apply+to+a+zoomable+interface+for+indices+of+difficulty+up+to+and+beyond+30+bits%2C+whereas+classical+Fitts%E2%80%99+law+studies+have+been+confined+in+the+2-10+bit+range.+The+second+study+demonstrates+a+strong+interaction+between+view+size+and+task+difficulty+for+multiscale+pointing%2C+and+shows+a+surprisingly+low+ceiling.+We+conclude+with+implications+of+these+findings+for+the+design+of+multiscale+user+interfaces.&rft.publisher=Elsevier&rft.contributor=Guiard%2C+Yves&rft.contributor=Beaudouin-Lafon%2C+Michel&rft.date=2004-12&rft.type=Journal+(Paginated)&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Fcogprints.org%2F4338%2F1%2FTarget_acquisition_multiscale_electronic_worlds.pdf&rft.identifier=++Guiard%2C+Yves+and+Beaudouin-Lafon%2C+Michel++(2004)+Target+Acquisition+in+Multiscale+Electronic+Worlds.++%5BJournal+(Paginated)%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F4338%2F