Viewers often fail to see objects, such as pedestrians and other vehicles. Such failures-to-see have great importance in safety as well as in many other domains such marketing, medicine, and sports, and elsewhere. I have discussed seeing in general and why failure-to-see is so common. Here, I provide a broad overview of the specific reasons for failures-to-see. I present these in tables that are adapted from the book Roadway Human Factors: From Science To Application (Green, 2017), which discusses them in detail. However, such categorizations inevitably begin to fray at the edges. They are didactic and an attempt at cognitively simplifying the large number of visual factors affecting seeing.
The reasons can very broadly be divided into visibility and cognitive. The first table shows 5 visibility factors. External physical factors are partial or complete sightline obstructions. Physiological factors can be optical, neural, or motor. Psychophysical factors usually boil down to those affecting contrast detection. Lastly, these five entries can readily be decomposed further. There are more than 16 subfactors in contrast alone (Green, 2017).
Level
Explanatory Factors
Description
Physical
External Obstruction
Physical obstructions completely or partially block the sightline and prevent retinal image formation: e.g. buildings A-pillars, windshields.
Physiological
Optical
Optical imperfections. Blur caused by mis-accommodation and spherical aberration. Cataracts and opacity.
Neural
Retinal limitations, e.g., field size, photoreceptor spacing, and scatomata.
Motor
Eye muscle movements also reduce vision, e.g., saccadic suppression and blinking.
Psychophysical
Contrast
Factors that determine whether an object differs sufficiently from the background to be visible: e.g., size, adaptation level, retinal eccentricity, etc.
In many cases, however, the cause of failure-to-see is cognitive – the viewer does not consciously see an object which is theoretically highly visible. The usual culprit is attention. The failure to see is especially likely in given circumstances. There is vast a literature on attention and cognition that provides many potential explanations for failure to see in a given set of circumstances. The table below boils this literature down to a single list of 28 cognitive failure-to-see “constructs” that are again grouped into rough categories purely for didactic purposes. Further, the chart constructs require further elaboration.
Cognitive (Learned Adaptation)
Expectancy
Attention tuned to the location and objects of highest anticipated meaningfulness, so others not noticed.
Automaticity
Tasks performed with minimal attentional control, so little attentional supervision to notice difficulties.
Familiarity Blindness
Failure to notice scene information that has been irrelevant in the past.
Cognitive(Loading)
Tunnel vision
Attention concentrated in the center of the visual field, so information in peripheral vision is unnoticed.
Inexperience
Novices have not yet learned to reduce foveal loading by chunking or by automatic control.
Stress Hypervigilance
Stress focuses attention on a narrow set of information, so other information not noticed.
Mental Workload
Attention consumed by one task leaves less capacity to perform others.
Cognitive(Selection)
Inattentional blindness
Failure to notice even highly visible objects located in the center of the visual field.
Change blindness
Failure to notice a feature alternation in a scene that has changed over time.
Mind wandering (Internal distraction)
Attention is focused internally rather than to the external world.
Repetition blindness
Second in a sequence of two identical objects is not noticed.
Foreground bias
Viewers tend to fixate objects in the foreground and to ignore objects in the background.
Cognitive (Background)
Clutter masking
Background contours interfere with attention to foreground objects. It is sometimes a psychophysical effect.
Overshadowing
Attention attracted to the most salient scene object and away from other information.
Cue generalization
Viewers direct attention to the most easily discriminated cue, such as color.
Crowding
Visible objects in peripheral vision merge and cannot be identified.
Motion induced blindness (MIB)
Object projecting retinally stable images tend to disappear when seen against moving backgrounds.
Cognitive(Search)
Satisfaction of search
Termination of serial search before reaching the critical information.
Inhibition of return
Once a scene area is searched, the probability of making a return saccade to re-search is reduced.
Visual space asymmetry
Different parts of the 3-D visual space are specialized for different attentional tasks.
Switching Costs/Attentional blink
Switching attention from one focus to another takes time and effort.
Cognitive(Reduced Capacity)
Fatigue/Lack Of sleep
Difficult to define, but usually explained as lowered performance due to lack of sleep.
Vigilance decrement
Ability to notice information falls within the first half hour in routine tasks.
Low Workload/Boredom/Monotony
Low arousal level with longer time spent in a dull and unchanging environment.
Circadian Rhythm
Arousal lower in troughs of the daily 24-hour arousal cycle.
Age
Older viewers are both slower and have lower attentional capacity.
Cognitive (Decision)
Biases & Heuristics
Attention and decision are guided by mental short cuts designed to increase efficiency.
Satisficing
Attention becomes unnecessary once a reasonable solution achieved.
The cognitive construct list is long, but the phenomena overlap considerably because they are different manifestations of our fundamental cognitive architecture and its consequences:
1) conscious awareness is limited by capacity,
2) attention is selective,
3) attention is efficient, trying to use the easiest and simplest selection criterion,
4) attention generally selects information that is most meaningful based on past experience and on expectation of the future. This overlap is why I call them “constructs” rather than variables or causes1. The criterion for inclusion in the list is only that the authors frequently use the “construct” to explain a cognitive failure-to- see. In many cases, the construct name specifies little more than an experimental paradigm, e.g. “change blindness”.
Lastly, the constructs also represent different granularities of explanation. “Inattentional blindness” (failure-to-see central objects) and “tunnel vision” (failure to see peripheral objects) are really just descriptive terms for phenomena that are ultimately caused by more specific constructs (expectation, hypervigilance, mental workload, etc.). They can be useful as umbrella terms when merely describing the functional loss, but they are not very specific. They are symptoms of deeper causes. They are not explanations.
Endnotes
1 The definition of “causation” is a knotty philosophical problem. In practice, however, it is often merely a “symptom” that doesn’t require an explanation. Causal reasoning normally works through a chain where symptoms have causes which then become symptoms for other causes. Here’s an example. A driver is blamed because he responded too slowly in seeing a pedestrian at night. Slow perception-response time is a symptom and low visibility is the cause. Low visibility is then the symptom, and a burned out streetlamp is the cause. The burned out streetlamp is now the symptom, and poor maintenance is the cause. Poor maintenance is the symptom… and so on. The chain stops when the symptom need not be explained. In this example, a human factors analysis doesn’t need to know what caused the streetlamp to be burned out, so the cause need not be determined. For an investigating utility company, the causal chain would continue until the poor maintenance were explained.
A major failing in trucking “defense” is that is seen as synonymous with “defensive”.
Too often trucking companies and their insurers hunker down after the accident, waiting for the bill board attorney to make their move. Worse yet, even after receiving the letter of representation, they sit by idly waiting for the plaintiff to dictate the time and place of the action.
Because too many see “defense” as meaning “defensive”. Enough!
THE NEED FOR AGGRESSIVE DEFENSE
Passive, reactive, “defensive defense” rarely if ever works. Aggressive, proactive “defenses” often do. And they do so by flipping the script on an opponent, even one that appears to be in stronger position.
Pick your example. Israel in 1966 compared to France in 1939. How did that “impregnable” Maginot Line work out?
How many times have you yelled at the TV when your favorite football team is ahead and decides to play “prevent defense”?
One of my favorite examples is from Malcolm Gladwell’s story of Vivek Ranadive, an immigrant from Mumbai who, despite having never played basketball, coached his daughter’s team to a national championship game despite only two of the girls having ever played organized basketball before.
“They weren’t all that tall. They couldn’t shoot. They weren’t particularly adept at dribbling.”
OK? So how did they do it?
Watching his first basketball game, Ranadive was struck by the illogic that after a basketball, the scoring team retreated and defended only about 24 feet of the 94 feet long court. “He thought it was mindless.”
So he applied the principle “that his team would play a real full-court press, every game, all the time. The team ended up at the national championships.”
Gladwell’s article expands the principle of aggressive defense to Lawrence of Arabia and David v. Goliath, the original pre-pay-per-view Match of the Century that has a scientific explanation. Great Read
And in case you think the full-court press, aggressive basketball only works with youth sports, ask a Razorback fan the name of Coach Richardson’s national championship style of play. Young ones—Google it.
The point is that too often trucking companies and their insurers only defend the last 24 feet of a 94 feet long contest. They concede the early going, even the middle going, and hunker down for a final skirmish.
You need to take the fight to them. Particularly after the letter of rep. Keep reading. I’ll get to it.
PROACTIVE, AGGRESSIVE TRUCKING DEFENSE
So what can you do? Hope the advertising plaintiff attorney won’t sue? Avoid antagonizing them and maybe they’ll be kind and gentle? How’s that been working for you?
Sounds ridiculous, but it is too often the “strategy”. If you can call sitting by passively and waiting for the attack a “strategy”.
BEFORE THE ACCIDENT
I’ve written and spoken a lot about pre-accident preparation, so let me just give a recap.
The highlights:
-Have an accident response plan in place NOW;
-Train your driver
-Thoughtfully select and train whomever is going to take “the call”;
-Preselect experts and ensure their 24/7 availability;
-Know what you need to do to preserve data—ECM, telematics, video,…;
-Review your safety plan, manual, training, …and prepare as if you will have to defend it at trial;
-Identify who is going to be the “face of the company” in a suit and prepare them.
Key—if you were on the witness stand, what evidence would you want to present? Develop it now. After the accident, it’s just back-fill.
WHEN THE ACCIDENT OCCURS
Act immediately. Investigate. Document. Get statements from witnesses. Do something!
We have an advantage that none of those daytime TV attorneys have—immediacy. We know about the accident before any of them. If we are not ready and act immediately, we will have squandered our greatest of assets.
Don’t rely on your insurer. If they act immediately-great. If not, protect yourself. In a world of high insurance rates and significant risk retention levels, it’s your money.
You can’t afford to sit by idly if your insurer delays in assigning an adjuster, opening a claim,…. One of my grandmother’s saying was, “the Lord helps those that helps themselves.” Act immediately. Help yourself.
Take the slack out out of the post-accident chain. Do something.
AFTER THE ACCIDENT
This is where the “hunker down”, “defensive defense” is tragically the norm. “What can we do except wait until they sue?” Answer—A lot.
Sue them first. If you have an argument as to liability and you’ve suffered damages (PD, cargo, downtime,…), sue them first. This gives you the jump on the cable TV attorneys by being able to subpoena records and propound discovery against the claimant who, at this point, is represented by the auto insurance company attorney.
More importantly, you have the potential to anchor jurisdiction in the location of the accident rather than allowing the plaintiff to drag you into a “hell hole” on the theory that you are a trucking company and can be sued anywhere. This can save you millions and the industry as a whole hundreds of millions of dollars.
You may even be able to prevent the claimant from if you get a judgement in your favor against the claimant. This can result in res judicata or collateral estoppel–legal terms for “you had your chance and you lost. Good bye.”
Someone recently told me that they do this. “We pursue subrogation on all our cases. We often get our money without having to sue.”
They’re missing the point. You might not want to get your money right away, otherwise you could lose being in a conservative jurisdiction. Sue them. Maximize your suit per discovery and jurisdiction.
Watch the Video Tease–learn what Coach Bill Walsh said before every big game that is the best advice for your defense. But…you have to watch the Video
Push back against the Letter of Representation. Shortly after the accident you will get the standard letter of representation from the advertising attorney—“This is my client. No further communications with them. What are your policy limits?”
Too often this is sent to the insurer after which it is filed it away and waiting for the inevitable. And all that time the claimant is running up medical bills from a doctor to which they are frequently referred by their attorney.
Do something. Push back. Have your attorney send a letter and say all communications are to be to them. And do more.
Include medical and employment record releases in that letter for the claimant to sign and return. Request a list of medical providers and employers. State your need for these records to promptly investigate the claim and potential prejudice if not provided. And do more.
Request that their client submit to an immediate medical examination. Again, make clear the prejudice that you will suffer is they do not agree to do so.
What responses do I get from the plaintiff attorneys when I do this? “I’ve never had this before.” Or, more often, “What right to you have to request an exam before suit?”
My answer? “None. But I’ve documented my request. If this goes forward, you and your client will have to explain why, if you were really injured, you would not let our doctor examine them.”
Quite frankly, I don’t care if they agree to it or not. If we get the exam, great. if not, we have documented the record as to our request. Documentation to challenge that ongoing treatment and medical expenses run up before they file suit.
BOTTOM LINE
We cannot concede an inch. We cannot make it easy for those who want to eat your lunch. That is exactly what “defensive defense” does.
Learn the lesson—full court press in defense of your company.
Labor costs for repair and maintenance increased 2.6% between Q1 and Q2, according to Decisiv’s and the American Trucking Associations’ Technology & Maintenance Council’s North American Service Event Benchmark Report. Overall, cost of parts increased by 2.8% in the same time period, with tires increasing 10.7% and the cost of transmission parts rising 9%.
But time between breakdowns is improving. TL carriers averaged 23,769 miles between breakdowns, up 8.8% from Q1, according to a survey by TMC and FleetNet America.
LTL carriers bettered their performance by 4.1% from Q1 to Q2, increasing to 46,186 miles from 44,380 miles, according to the TMC/FleetNet America survey. The tank sector had a 4.7% improvement, running 18,241 miles in Q2, up from 17,420 in Q1.
Dive Insight:
Unscheduled maintenance and breakdowns have been a rising cost issue since early 2020, but now the issue of inflation appears to be rearing its head. Costs have been spiraling upward for quite some time.
The arrival of COVID-19 worsened the costs, not because the raw materials behind steel and rubber became more rare, but because the supply chain slowed at first and is now currently experiencing congested ports and backed-up orders.
Costs for actual parts are also going up, along with the labor costs associated with breakdowns and even regularly scheduled maintenance.
“The increases in costs for parts and labor reflect the changes taking place in the North American economy,” said Dick Hyatt, Decisiv president and CEO. “Ongoing economic growth has led to a rise in freight volume and demand for carrying capacity. That is also being driven higher by the need to replenish supply chains that have been depleted due to manufacturing and distribution shutdowns during the pandemic.”
Hyatt said increased transport demand pushed up vehicle mileage and usage.
The heavy parts, as well as the electrical parts, went up by doubles digits. Lighting systems increased 17.4% in Q2 from a year earlier, transmissions costs were up 16.4% in the same time frame, and brakes costs increased 11.1%.
Emily Hurst, manager of data and analytics at FleetNet, said fleets seeking to cut costs need to mimic the habits of the best-in-class fleets in the TL, LTL and tanker divisions.
Such habits could include reinforcement and better insulation put around electric wiring and lighting lines to prevent problems that put out lights.
The Decisiv/TMC North American Service Event Benchmark measures results in 7 million commercial vehicles operating in the United States and Canada, serviced by Decisiv’s SRM platform. The surveys on unscheduled maintenance and general costs were both released before TMC’s fall meeting.
A group of researchers from Northeastern University and the University of Arkansas issued a report this February “Did Electronic Logging Device Mandate Reduce Accidents?” which analyses the effects of the electronic logging device mandate, and they reached two main conclusions:
The use of ELDs has not reduced the rate of truck crashes
The frequency of speeding violations, particularly among the small carrier segment, has increased since the mandate took effect
The report mostly focuses on smaller carriers and owner-operators who were considered the most impacted by the mandate, since larger carriers were likely already using ELDs or AOBRDs.
Although there were fewer hours of service violations, crash numbers saw little impact by the enforcement of the ELD mandate.
The report studied drivers between January 1, 2017 and September 1, 2018, which included:
Nearly a year’s worth of data prior to the December 18, 2017, enforcement deadline of the ELD mandate, and
Roughly three-month light enforcement period ahead of the April 1, 2018, hard enforcement date
For the pre-enforcement period, researchers said there was an average of 1,717 truck crashes a week. That number spiked during the soft enforcement period (December 17, 2017, to April 1, 2018) to 1,912 crashes a week. After April 1, the number dropped to an average of 1,703 crashes per week.
Independent owner-operators averaged 154 crashes a week prior to the ELD mandate December 2017 deadline and 160 crashes after hard enforcement began in April 2018.
Drivers at carriers with between 101 and 1,000 truck averaged 374 crashes a week before the mandate and 361 crashes a week after hard enforcement began.
Carriers with 1,001 or more trucks saw their crash rates dip slightly, from 244 a week to 240 a week.
Based on this data, the researchers conclude that these numbers do not point to any obvious reduction in accidents due to the ELD mandate.
While accident rates appear unchanged, the report says, unsafe driving behaviors such as speeding appear to have increased over the same period of time. These unsafe driving behaviors were found to be in response to productivity losses caused by the mandate.
According to the report, unsafe driving violations:
By owner-operators increased by as much as 33.3%, and speeding increased by as much as 31%
Carriers with between 101 and 1,000 trucks saw only a 6% increase in the number of unsafe driving violations per week after hard enforcement of the mandate began
Carriers with more than 1,000 trucks saw a 12% increase in unsafe driving violations after ELD enforcement began
“We find that the ELD mandate unequivocally enhanced HOS compliance,” the researchers write. “However, the ELD mandate did not noticeably improve safety, and we are able to produce no statistically significant evidence that ELD adoption by the smaller firms corresponded to any reduction in accident rates.”
Fleets using in-cab cameras said they pay for themselves within months, as video exonerates drivers in crashes and drops insurance premiums.
Jim Stinson
When Keith Wilson proposed having an in-cab camera system for the trucks at Sharp Transport, the idea did not go over well with some drivers.
The system raised privacy concerns with drivers, not least of which was the fear that in-cab cameras would record while the truck was parked and the driver was sleeping. A few drivers threatened to quit the fleet if Sharp went ahead and installed the rectangular units, which would produce four different camera angles from the cab.
Wilson, Sharp’s director of safety and recruitment, knew he had to address the concerns before he implemented the policy change. After proposing the idea, Sharp contacted the chairman of the driver council the next day, said Wilson. “We met with the [council] a few weeks later to discuss and answer questions.”
“We showed them everything the camera did, and everything they did not.”
The list of concerns soon narrowed, with drivers asking if the cameras would be able to peer into the sleeper areas.
“The biggest objection obviously was the driver-facing cameras,” said Wilson. “We showed them everything the camera did, and everything they did not.”
One thing the cameras do not do is record when the keys leave the ignitions, Wilson said. The cameras even go inactive if a truck is idle for three minutes. And most important to drivers, the unit did not record the sleeper area, he told drivers.
Out of 150 Sharp Transport drivers, only three left the company after in-cab cameras were installed, Wilson told a WorkHound webinar last summer.
Then the policy paid off. Costs went down, and the cameras “paid for themselves.” Wilson said it only took eight months for the return on investment.
For truck drivers, often blamed for accidents, the in-cab video became a useful piece of evidence to show the police. Sometimes truck drivers were exonerated “on the spot” following an accident, after police reviewed the video, Wilson said.
“It changes the narrative really quickly,” said Wilson.
The video benefits
Alan Drazen, vice president of Simco Logistics, said its Samsara-branded video cameras have indeed exonerated the company’s drivers. But Drazen pointed to other benefits from the cameras, as well.
“The biggest change for us was the culture change,” said Drazen.
From safety to “harsh events” such as sudden braking, the cameras have proven their benefit by improving the company’s safety record, Drazen said.
The New-Jersey-based company has 160 trucks, Drazen said. The Samsara in-cab cameras have cut use of personal electronic devices by about 90%, he said. The video cameras, which can upload videos immediately after a harsh event is detected, are also used for driver coaching, tips and discipline.
As for privacy concerns, the drivers still have them, even though Simco has no overnight drivers. But Drazen tells the drivers that video is only uploaded to him under certain circumstances.
“If they don’t do harsh events, we’ll never see [the drivers],” said Drazen.
In three years of usage, Simco’s insurance premiums have dropped, Drazen said, as the company’s “culture of safety” grows.
“Right now, we are paying about 60% of what we were paying before the cameras,” said Drazen. “And [insurance premiums have] been dropping every year.”
Drazen said Simco agreed to a five-year prepayment for the Samsara cameras and service. The ROI was quickly recognized.
“We got a full recovery in costs in 18 months,” said Drazen. “It’s unbelievable.”
Drazen said he now promotes the cameras to other fleets.
“It makes it safer for everybody,” said Drazen.
Wilson said the time from idea to implementation of in-cab cameras relatively short, and the ROI came quickly.
“The proposal and vetting process took about a month to complete. Two weeks to finalize the financial aspect, a week to have shop personnel trained to install,” Wilson said. “We estimated three months to install in all units.”
From skepticism to support
The cameras can notify dispatch offices immediately after a harsh event. In Samsara’s case, the cameras can upload video immediately via cellular networks.
As with Sharp Transport, the first strategy advised was meeting with drivers and transparency. And during those meetings, showcase real exoneration footage, the blog states.
“We got a full recovery in costs in 18 months. It’s unbelievable.”
“Successfully exonerating drivers is the most powerful way to get skeptical drivers in support of dash cams,” the blog, written by Samsara product marketing manager Eleanor Horowitz, said. “If you have an example of a near-miss or not-at-fault collision that was captured during a pilot, share the footage with all of your drivers.”
Wilson said there is no legal precedent that favors violations of privacy for company-owned vehicles.
“We did have to compromise with our owner-operators,” said Wilson. “They agreed to have the cameras installed on all of their vehicles with the option to have the driver-facing camera turned off.”
Privacy issues aside, Samsara makes the lure of decreasing accidents and premiums the main selling point in the promotion of the cameras. The company, on its blog, cited a June report by Frost & Sullivan. The report noted the FMCSA estimates that 71% of large-truck crashes occur due to driver distraction.
“Unsafe practices, including texting or calling while driving, increase the likelihood of crashes,” the report reads. “They also affect a fleet’s brand image and reputation, while creating challenges related to driver retention.”
Frost & Sullivan concludes that the U.S. and United Kingdom market for such cameras will grow by 22.2% from 2018 to 2025, surpassing 3.5 million units by 2025.
Wilson said Sharp’s accidents have dropped 125% since cameras were installed, and part of the reason is the psychology involved.
“Just having the camera in-cab changes behavior,” said Wilson.
