human factors exam 1
Most people over the age of 50 can't focus on objects nearer than ____________________ without glasses.
1 meter
Limits of visual acuity have many important consequences ranging from reading to guiding action. A visual angle of one minute corresponds to 1.05 inches at _______________ yards, similar to the accuracy of a highquality rifle, suggesting the need for a scope to benefit from rifles' accuracy.
100
The color rendering index (CRI) describes the ability of a lamp to render color accurately with _____________ being a perfect score, rendering colors in a manner similar to sunlight.
100
The lighting requirements for these tasks range from 20 to _______________ lux. For comparison, moonlight generates 1 lux, sunrise and sunset 400 lux, shaded area at midday 20,000 lux and bright sunlight 100,000 lux
20,000
The lowest perceptual frequency of sound is approximately 20Hz and the highest is approximately _______________________________?
20,000 Hz
Road signs use a legibility index to define how large the lettering should be. A legibility index of ______________ , which is the current standard, indicates the size of capital letters should be one inch for every 30 feet for the sign to be readable. At 300 feet, the letters should be 10 inches high.
30
A characteristic that limits the effectiveness of color is that approximately _______________ of the male population is color deficient; that is, they are unable to discriminate certain hues from each other. Most prevalent is red-green "color blindness" (protanopia) in which the wavelengths of these two hues create identical sensations if they have the same luminance intensity
7%
The range of wavelengths typically visible to the eye runs from short wavelengths of around 400 nm (typically observed as blue-violet) to long wavelengths of around __________________
700 nm
OSHA has taken steps to protect workers from hazardous effects of prolonged noise in the workplace by establishing standards. Even brief exposure to sounds over 100 dB can cause permanent hearing damage, but sounds of ___________ can lead to hearing damage with prolonged exposure
85dB
One type of in-service evaluation, _________________________________, is where one version of a system is compared to another version of the system, where one is typically an improvement over the existing system. This type of testing is very common for internet application, where thousand of tests provide data to guide screen layout and even shades of color.
A-B testing
Beyond evaluating specific systems or products, human factors engineers also evaluate more general design concepts and develop design principles. Such ___________________________________ reflects the basic science that supports the design principles and heuristics that make it possible to guide design without conducting a study for every design decision
Concept evaluation
Given the following steps for conducting a controlled experiment, match the description to the steps to place them in sequential order.
Define research questions and hypothesis - Step 1 Specify the experimental design - Step 2 Conduct the study - Step 3 Analyze the data - Step 4 Draw conclusions - Step 5
________________________________________ identifies the independent variables that will be controlled in the study, and the dependent variables or outcomes of interest to mbe measured and observed. Only the independent variables should be manipulated, and all other variables shouuld be held constant.
Experimental design
*When describing the effect on hearing, the amplitude of sound is expressed as the ratio of ___________________ to a reference P0.
Hz (wrong)
___________________ can serve as a useful starting point for human factors evaluation.
Literature Review
As we grow older, the lens becomes less flexible in general, but farsightedness in particular becomes more evident. ___________________ or farsightedness—from the Greek words "aged" and "eye", results when the lens cannot accommodate to very near stimuli.
Presbyopia
In measuring the quality of speech communication, a measure that takes top-down processing into account and directly measures the percentage of items correctly heard is the __________________________?
Speech Intelligibility Index
Both qualitative (such as open ended surveys) and quantitative (such as task analysis) evaluation methods may be used for this purpose
Understand
The primary purpose of evaluation include all the following except
Verify product meets requirements (formative)
Discrimination refers to judgment of differences between two sources of information that are actually (or potentially) present, and generally people ATS Canvas Support are good at this task as long as the differences are not small and the viewing conditions are favorable. In contrast, ______________________ refers to the limited human capability to judge the absolute value of a variable signaled by a coded stimulus.
absolute judgement
The lens of the eye ____________________________________ to bring the image to a precise focus on the back surface of the eyeball, the retina. This is accomplished by a set of ciliary muscles surrounding the lens.
accomodates
The amount of fine detail that can be resolved is far greater when the image falls on the closely spaced cones than on the more sparsely spaced rods. We refer to the ability to resolve detail as the_______________, often expressed as the inverse of the smallest visual angle (in minutes of arc) that can be detected.
acuity
Specific design criteria for alarms should avoide two opposing problems, difficulty in detection and ____________________________?
annoyance
Judgment of depth and distance for more distant objects and surfaces depends on a host of what are sometimes called "pictorial" cues because they are the kinds of cues that artists put into pictures to convey a sense of depth. Because the effectiveness of most pictorial cues is based on past experience, they are subject to top-down influences. Some of the important pictorial cues include the following except ____________________________.
antireflection
For _________________________________, we try to identify tasks and environments that provide results that predict outcomes of our human factors interventions in the particular situation of their application. For _____________________________, we try to identify tasks and environments that generalize accross many situations beyond those included in the study
applied research, basic research
Mental processes lie at the core of much information processing in complex environments. The characteristics of human cognition presented have many detailed implications for desigs. A few broad design considerations include the severe limits of attention and working memory: people can hold only three or four things in memory, and if they try to do two activities at once, one or both will suffer. Chunking, unitization, and _________________________ mitigate these limits.
automaticity
Designers frequently fail to realize or predict the difficulty people will experience in using their system. One reason is that they are extremely familiar with the system and have a very detailed and complete mental model. The often write owners' manuals as if they will be read thoroughly and all of the information will be remembered for the life of the equipment. Even with very clear instructions for using features of our new car, the typical driver is unlikely to read the owners' manual thoroughly. To deal with implications of long-term memory decline in design all of the following strategies should be considered except ____________________________?
avoid the use of memory aids
To judge our distance from objects (and the distance between objects) in 3-D space, we rely on a host of depth cues to inform us of how far away things are. These cues include the following except
binocular interference
When stimulated by light, rods rapidly lose their sensitivity, and it takes a long time for them to regain it (up to a half hour) once they are returned to the darkness. This characteristic of the rods' optimal viewing environment. This phenomenon describes the temporary ________________________ we experience when we enter a darkened movie theater on a bright afternoon
blindness
The __________________________ of a stimulus, then, is the actual experience of visual intensity, an intensity that often determines its visibility
brightness
The primary mechanisms of working memory including all of the following except _________________________________________?
cache buffer
A source of light may be characterized by its luminous intensity, or luminous flux, which is the actual light energy of the source measured in units of _____________.
candela
Regarding human factors evaluation methods, a ___________________________ considers each task associated with a system interaction, and poses a series of questions to highlight potential problems that might confront someone trying to actually perform the sequence of tasks.
cognitive walkthrough
A _______________________________ evaluation typically includes data from a controlled experiment and provides a more inclusive, summative assessment of the system than a usability evaluation
comprehensive system
The middle region of the retina, the fovea, consisting of an area of around 2° of visual angle, is inhabited exclusively by ____________________.
cones
In designing a study, consider all variables that might affect the dependent variables. Extraneous variables have the potential to interfere in the causal relationship of interest and must be controlled. If these extraneous variables do influence the dependent variable, we say they are _________________________________.
confounding variables
Specific considerations for making text more readable follow from the mechanisms underlying contrast sensitivity. Because of certain asymmetries in the visual processing system, ____________ text on lighter background ("negative contrast") offers higher contrast.
dark
Sound reflection off walls or other surfaces is termed reverberation. Reverberation has all of the following effects except _______________________________________?
decrease sound pressure below predicted levels
It is important for the designer to consider alternative controls, especially if they must be reached and manipulated for activation or to consider alternative displays that must be interpreted and perceived. Are they far enough apart in space, or can they be distinguished by other features, such as color, shape, or other labels, to minimize confusion? Can they be adequately ____________________________?
discriminated
The TWA equation shows how the percent of a permissible dose of sound depends on time exposures to different noise levels. All noise exposure over 80dBA must be integrated into the equation Because the noise exposure varies from worker to worker and varies depending on the location within the facility, in potentially high noise environments it is best to have employees wear _________________ to collect data needed to compute the TWA over the course of the day.
dosemeters
In less typical reading situations, such as reading displays while driving, vibration and the requirement to quickly glance back to the road suggests the need for text that is larger than the critical print size. Guidelines for automotive displays (e.g., warning messages, navigation systems, speedometer labels) suggest a visual angle for display text that is roughly _______________________ that of the critical print size and consistent with that recommended for cockpit displays.
double
*Because the power intensity of sound is proportional to the square of the distance, each doubling of the distance away from the source leads to a ____________ decline in the intensity of the sound.
exponential (wrong)
Stereopsis, is a depth cue that results because the closer an object is to the observer, the greater the amount of disparity there is between the view of the object received by each __________________
eyeball
A multi-factor design that evaluates two or more independent variables by combining the different levels of each indepenent variable is called a _______________________________?
factorial design
Signal detection performance depends on considering not just signals detected but also ________________________.
false alarms
Useful _________________________ describes the area around the fixation that people can extract information in a brief glance.
field of view
The amount of energy that actually strikes the surface of an object—the road sign, for example—is a very different measure, described as the illuminance and measured in units of lux or ______________________.
foot-candles
The time weighted average (TWA) of noise combines intensity of exposure with exposure durations. If the TWA exceeds 85dBA (a weighted measure of noise intensity), known as the action level, employers are required to do all of the following except ________________________________________?
free hearing aides
The stimulus for hearing is sound, which is a compression and rarefaction of the air molecules, represented by sine waves each having an amplitude and ___________________.
frequency
Lying just under the skin are sensory receptors that respond to pressure on the skin and relay their information to the brain regarding the subtle changes in force applied by the hands and fingers (or other parts of the body) as they interact with physical things in the environment. Along with the sensation of pressure, these senses, tightly coupled with the proprioceptive sense of finger position, also provide ____________________ regarding the shape of manipulated objects and thing
haptic information
Habits form with repetition of an activity that occurs in a consistent context. Once established, habits occur effortlessly and actually require cognitive resources and effort to avoid. This makes bad habits _____________ to break.
hard
Most commonly when people use dBs to refer to sound intensity they mean sound amplitude pressure or intensity as measured on the decibel scale, relative to P0, the threshold of __________________________.
hearing
In a ____________________________________, a human factors engineer applies rules of thumb, principles and guidelines - to identify ways to improve a design.
heuristic evaluation
An ___________________________________ refers to evaluations conducted after a design has been releases, such as after a car has been on the market, after a modified manufacturing line has been placed in servies, or after a new smartphone operating system has been releases.
in-service evaluation
In analyzing data from designed experiments we often use descriptive statistics and data visualization as a way to summarize the dependent variables for the different treatment conditions, while we use ________________________ statistics to tell us the likelihood that any differences between our experimental groups are "real" and not just random fluctuations due to chance.
inferential
To increase the likelihood that information will be remembered at a later time, it should be processed in working memory frequently and in conjunction with other information in a meaningful way. A particularly powerful way to reinforce a memory is to recall it just before it is forgotten. The decay of item strength and association strength takes the form of an exponential curve, where people experience a very rapid decline in memory within the first few days. Memory retrieval often fails because of the following except ___________________________________?
insufficient testing in training
Task switching emerges when the joint competition for resources between the two tasks is simply so great as to make concurrent processing impossible. In such cases, we say that workload "exceeds the red line". Under such circumstances, the multi-tasker must choose to continue one task and abandon the other altogether, thus entering a sequential mode of multitasking, where the multitasker must now switch between tasks. Discrete task switching then leads to two sequential multitasking phenomena: voluntary switching and _________________ management.
interruption
One of the activities for which working memory is used is to create a more permanent representation of the information in long term memory, where it may be retrieved minutes, hours, days, or years later. These are the processes of _________________ (putting information into long-term memory) and retrieval
learning
While visual acuity drops rapidly toward the periphery, the sensitivity to motion declines at a far ___________________ rate.
lesser
Working memory is relatively transient and limited to holding a small amount of information that may be rehearsed or "worked on" by other cognitive processes. It is the temporary store that keeps information available while we are using it, until we use it, or until we store it in _________________ memory
long term
Luminance is different from illuminance because of differences in the amount of light that surfaces either reflect or absorb. We can define the reflectance of a surface as ________________________.
luminance/illuminance
Five steps can help mitigate the problems of false alarrms, including all of the following except _______________________________________?
mask the raw alarm data to avoid confusion
When the human factors engineer is considering implication working memory in a design, the following factors should all be considered except ________________________________?
maximiz working memory workload
The following are important implications for human design in dealing with seletive attention, except ___________________________?
maximize top-down processing when bottom -up processing may be poor, by eliminating the possibility for guessing
Located deep within the inner ear are two sets of receptors, located in the semicircular canals and in the vestibular sacs. These receptors convey information to the brain regarding the angular and linear accelerations of the body respectively. The vestibular sacs provide the constant information about the accelerative force of gravity downward, and hence they are continuously used to maintain our sense of balance. Two important (and potentially negative) roles here, related to spatial disorientation and ________________
motion sickness
In any of a variety of tasks, the process of signal detection can be modeled by signal detection theory, which assumes that "the world" (as it is relevant to the operator's task) can be modeled as either one in which the "signal" to be detected is present or absent, an the world is assumed to contain ______________________ which makes signal detection more difficult.
noise
Properties of the cognitive environment govern how people come to understand and respond to the world around them. Important dimensions of the cognitive environment include all of the following except _______________________________?
noise, amount of noise present
Subjective ratings are often contrasted with ______________________ performance data, such as error rates or response rates. The difference between these two classes of measures is important, given that subjective measures are often easier and less expensive to obtain, with a larger sample size.
objective
It is apparent from the description of working memory and long-term memory that we do not put isolated pieces of information in long-term memory the way we would put papers in a filing cabinet. Instead, we store items in connection with related information. Long term memory is organized in the following ways except _________________________________________?
orthogonal maps
Only cones enable color vision, and so the extent to which hues can be resolved declines both in _________________________ vision (where fewer cones are present) and at night.
peripheral
The selection of channels to focus attention is typically driven by the following factors except ____________________________
propensity
A a rich set of receptor systems, located within all of the muscles and joints of the body, convey to the brain an accurate representation of muscle contraction, joint angles, and limb position in space. The____________ channel is tightly coupled with the kinesthetic channel, receptors within the joints and muscles, which convey a sense of the motion of the limbs as exercised by the muscles. One particular area of relevance for these senses is in the design of manipulator controls, such as the joystick or mouse with a computer system, the steering wheel on a car, the clutch on a machine tool, and the control on an aircraft.
proprioceptive
When considering ethical factors of experiments that involve people, the American Psychological Association guidelines advocate all of the following methods for protecting participants except __________________________________________.
protection from fatigue
Contrast sensitivity may be defined as the ______________ of the minimum contrast between a lighter and darker spatial area that can just be detected (CS=1/Cmin); that is, with a level of contrast below this minimum, the two areas appear homogeneous.
reciprocal
When we examine the effects of noise, we consider the three main components of potential hearing loss which include the following except
reflection, sound delayed less than 50ms
An information processing model describes the cognition process which includes perceiving, thinking about (central processing) and
responding
To guarentee informativeness and to minimize confusability, designers should try to make alarm sounds as different from each other as possible by capitalizing on the various dimensions along which sounds differ, which include all except __________________?
reverberation
All of the following factors can influence conspicuity except _________________________
reversability
A critical aspect of human performance in many systems concerns the closely linked processes of visual search and object detection. Eye movements are necessary to search the visual field . Eye movements can be divided into two classes. Pursuit eye movements are those of constant velocity that are designed to follow moving targets, for example, following the rapid flight of an aircraft across the sky. More related to visual search are _______________eye movements , which are abrupt, discrete movements from one location to the next designed to bring a visual item into foveal vision.
saccadic
__________________ primarily contributes to the bottoms-up process of allocating attention, influencing attentional capture, which occurs when the environment directs attention.
salience
The pure wavelengths, characterizing a hue, like blue or yellow, may be "diluted" by mixing with varying amounts of gray or white (called achromatic light). This is light with no dominant hue and therefore not represented on the spectrum. When wavelengths are not diluted by gray, like pure red, they are said to be ___________________.
saturated
The rods have an advantage in terms of ___________________ characterizing the minimum amount of light that can be detected, which is the threshold. Scotopic vision refers to vision at night when only rods are operating.
sensitivity
Long-term memory can be distinquished by the following characteristic types except ______________________________?
sensory memory
Usability is primarily the degree to which the system is easy to use, or "user friendly." This translates into a cluster of factors, including the following variables except ____________________?
socialability
The scale that relates physical intensity to the psychological experience of loudness, is expressed in units called ______________________?
sones (wrong)
The working memory holds two primarily different types of information including verbal and ____________________________?
spatial
In poorly illuminated viewing conditions, the loss of contrast sensitivity at all _______________________ can inhibit the perception of print as well as the detection and recognition of objects by their shape or color which means that night driving for the older population is a hazardous undertaking, particularly in unfamiliar territory
spatial frequencies
For single, isolated words, UPPERCASE may be better than lowercase print, as, for example, the label of an "on" switch. This advantage results in part because of the wider visual angle and lower spatial frequency. However, for multiword text, UPPERCASE PRINT IS MORE DIFFICULT TO READ than lowercase or mixedcase text because this eliminates the contributions of this lower ___________________channel.
spatial frequency
A given light stimulus can be characterized by all of the following except ________________.
speed
The amount of illuminance an object receives depends on the distance of the object from the light source—the illuminance declines with the
square
Six factors that affect human multitasking capabilities include all of the following except __________________________________?
task integration
The point where you are in the design process (understand, create, evaluate) as well as the following are critical considerations in selecting an evaluation method
time available
In a search the time to detect any target can be expressed as a function of N the number of targets, and I the _____________________________
time to inspect each target
The inner ear, consisting of the cochlea, within which lies the basilar membrane, is where the physical movement of sound energy is transduced to electrical nerve energy that is then passed through the auditory nerve to the brain. This transduction is accomplished by displacement of _________ along the basilar membrane as the membrane moves differently to sounds of different frequency
tiny hair cells
The distinction between the effortful processing of feature analysis and the more automatic processing of familiar __________________ feature combinations (whose combined representation is stored in long-term memory), can be applied to almost any perceptual experience, such as perceiving symbols and icons.
unitized
Literature reviews, heuristic evaluations, and cognitive walk-throughs do not involve collecting data from people interacting with the system, which ATS Canvas Support makes them faster to apply to a system and so are particularly useful. However these methods are susceptible to analysts bias, which makes _________________ essential as a formative technique to help diagnose problems and identify opportunities for improvement as part of an iterative development process
user testing
Expectancy and ______________________ together define top-down or knowledge-driven factors in allocating attention. That is, we tend to look at, or "sample," the world where we expect to find valuable information
value
An image, whether focused or not, eventually reaches the retina at the back of the eyeball. The image may be characterized by its intensity (luminance), its wavelengths, and its size. The image size is typically expressed by its _________________.
visual angle
Text or font size is often measured in points, where a point equals 1/72 of an inch. For reading, the critical measure of font is the ___________ height, which corresponds to the height of the lower case letter _________, and the font size is roughly twice this value. The height is relevant because people must resolve the detail in lower case letters to read
x