/ txbgcolor = (175, 175, 255) / screencolor = (255, 255, 255) / txcolor = (175, 175, 255) / inputdevice = mouse / file = "mailto:seandr@millisecond.com" ***********************insects/flowers Discrimination***************** / select = noreplace(10-90) / select = noreplace(20-80) / shape=circle / size=(30,30) / hposition = hcounter / vposition = vcounter / shape=circle / size=(55,55) / hposition = hcounter / vposition = vcounter / shape=circle / size=(80,80) / hposition = hcounter / vposition = vcounter / shape=circle / size=(60,60) / position = (50, 50) / color=(0,255,0) *************************** Instructions ******************* / nextlabel = "Next" / lastlabel = "Start" / inputdevice = mouse / font = ("Arial", -19, 700, 0, 34) Fitt's Law Demo ^^Fitts' Law is a human factors model to account for the time it takes to point at something, based on the size and distance of the target object. The law states that big targets at close distance are acquired faster than small targets at long range, or, more precisely: ^^T = k log2(D/S + 0.5), k ~ 100 msec. ^T = time to move the hand to a target ^D = distance between hand and target ^S = size of target ^^To test Fitt's law, you will be shown a series of circles on the screen. Your task is to click on the circles as fast as you can! ^^Performance summary: ^^Average response time with the small circle: <% trial.small.meanlatency %> milliseconds. ^^Average response time with the medium circle: <% trial.medium.meanlatency %> milliseconds. ^^Average response time with the large circle: <% trial.large.meanlatency %> milliseconds. ^^^Demo complete! *************************** insects/flowers********************** / correctresponse = (start) / stimulusframes = [1=start] / correctresponse = (small) / stimulusframes = [1=small] / correctresponse = (medium) / stimulusframes = [1=medium] / correctresponse = (large) / stimulusframes = [1=large] / preinstructions = (begin2) / trials = [1,3,5,7,9,11,13,15,17,19, 21, 23, 25, 27, 29=start; 2,4,6,8,10,12,14,16,18,20, 22, 24, 26, 28, 30 = noreplace(small, medium, large)] ************************** Experimental Code ************************ / preinstructions = (begin) / blocks = [1=fitts] / postinstructions = (summary, end)