Non-experts have high rates of success of lie detection when viewing experts work
Originally published: August 21, 2014
Determining deception is a tool of the trade for law enforcement. The Good Cop/Bad Cop routine is etched in our minds as an effective method of finding out the truth. But prior research has shown that lie detecting is a 50/50 shot for experts and non-experts alike. So what exactly can we do to find out the truth? A recent study published in Human Communication Research by researchers at Korea University, Michigan State University, and Texas State University – San Marcos found that using active questioning of individuals yielded near-perfect results, 97.8%, in detecting deception.
Timothy Levine, Hee Sun Park (University of Korea), David Daniel Clare, Steve McCornack, Kelly Morrison (Michigan State University), and J.Pete Blair (Texas State – San Marcos) published their findings in the journal Human Communication Research. The researchers conducted three studies based on sets of participants who were asked to play a trivia game. Unbeknownst to the participants, a confederate was placed with them offering an incentive and opportunity to cheat at the game, since cash prizes were involved. In the first experiment 12% of the subjects cheated; in the second experiment 44.9% cheated.
An expert using the Reid Technique interrogated participants in the first study, this expert was 100% accurate (33 of 33) in determining who had cheated and who had not. That kind of accuracy has 100 million to one odds. The second group of participants were then interviewed by five US federal agents with substantial polygraph and interrogation expertise. Using a more flexible and free approach (interviews lasted from three minutes to 17 minutes), these experts were able to accurately detect whether or not a participant cheated in 87 of 89 interviews (97.8%). In the third study, non-experts were shown taped interrogations of the experts from the previous two experiments. These non-experts were able to determine deception at a greater-than-chance rate – 79.1% (experiment 1), and 93.6% (experiment 2).
Previous studies with “experts” usually used passive deception detection where they watched videotapes. In the few studies where experts were allowed to question potential liars, either they had to follow questions scripted by researchers (this study had no scripts) or confession seeking was precluded. Previous studies found that accuracy was near chance – just above 50%.
“This research suggests that effective questioning is critical to deception detection,” Levine said. “Asking bad questions can actually make people worse than chance at lie detection, and you can make honest people appear guilty. But, fairly minor changes in the questions can really improve accuracy, even in brief interviews. This has huge implications for intelligence and law enforcement.”
Originally published: August 21, 2014
A new, ultrathin film that is both transparent and highly conductive to electric current has been produced by a cheap and simple method devised by an international team of nanomaterials researchers from the University of Illinois at Chicago and Korea University.
The film is also bendable and stretchable, offering potential applications in roll-up touchscreen displays, wearable electronics, flexible solar cells and electronic skin. The results are reported in Advanced Functional Materials.
The new film is made of fused silver nanowires, and is produced by spraying the nanowire particles through a tiny jet nozzle at supersonic speed. The result is a film with nearly the electrical conductivity of silver-plate — and the transparency of glass, says senior author Alexander Yarin, UIC Distinguished Professor of Mechanical Engineering.
“The silver nanowire is a particle, but very long and thin,” Yarin said. The nanowires measure about 20 microns long, so four laid end-to-end would span the width of a human hair. But their diameter is a thousand times smaller — and significantly smaller than the wavelength of visible light, which minimizes light scattering.
The researchers suspended the nanowire particles in water and propelled them by air through a de Laval nozzle, which has the same geometry as a jet engine, but is only a few millimeters in diameter.
“The liquid needs to be atomized so it evaporates in flight,” Yarin said. When the nanowires strike the surface they are being applied to at supersonic speed, they fuse together, as their kinetic energy is converted to heat.
“The ideal speed is 400 meters per second,” Yarin said. “If the energy is too high, say 600 meters per second, it cuts the wires. If too low, as at 200 meters per second, there’s not enough heat to fuse the wires.”
The researchers applied the nanowires to flexible plastic films and to three-dimensional objects. “The surface shape doesn’t matter,” Yarin said.
The transparent flexible film can be bent repeatedly and stretched to seven times its original length and still work, said Sam Yoon, the corresponding author of the study and a professor of mechanical engineering at Korea University.
Earlier this year, Yarin and Yoon and their colleagues produced a transparent conducting film by electroplating a mat of tangled nanofiber with copper. Compared to that film, the self-fused silver nanowire film offers better scalability and production rate, Yoon said.
“It should be easier and cheaper to fabricate, as it’s a one-step versus a two-step process,” said Yarin. “You can do it roll-to-roll on an industrial line, continuously.”
A South Korean research team has developed new technology to improve tabletop holographic displays
Princess Leia, your Star Wars hologram moment may be redeemed. In the original ‘Star Wars’ movie, the inviting but grainy special effects hologram might soon be a true full-color, full-size holographic image, due to advances by a South Korean research team refining 3-D holographic displays.
The team described a novel tabletop display system that allows multiple viewers to simultaneously view a hologram showing a full 3-D image as they walk around the tabletop, giving complete 360-degree access. The paper was published this week in the journal Optics Express, from The Optical Society (OSA).
To be commercially feasible in a range of applications — from medicine to gaming to media — the hologram challenge is daunting. It involves scaling an electronic device to a size small enough to fit on a table top, while making it robust enough to render immense amounts of data needed to create a full-surround 3-D viewing experience from every angle — without the need for special glasses or other viewing aids.
“In the past, researchers interested in holographic display systems proposed or focused on methods for overcoming limitations in the combined spatial resolution and speed of commercially available, spatial light modulators. Representative techniques included space-division multiplexing (SDM), time-division multiplexing (TDM) and combination of those two techniques,” explained Yongjun Lim, of the 5G Giga Communication Research Laboratory, Electronics and Telecommunications Research Institute, South Korea. Lim and his team took a different approach. They devised and added a novel viewing window design.
To implement such a viewing window design, close attention had to be paid to the optical image system. “With a tabletop display, a viewing window can be created by using a magnified virtual hologram, but the plane of the image is tilted with respect to the rotational axis and is projected using with two parabolic mirrors,” Lim explained. “But because the parabolic mirrors do not have an optically-flat surface, visual distortion can result. We needed to solve the visual distortion by designing an aspheric lens.”
Lim further noted, “As a result, multiple viewers are able to observe 3.2-inch size holograms from any position around the table without visual distortion.”
Building on these advances, Lim’s team hopes to implement a key design feature of strategically sizing the viewing window so it is closely related to the effective pixel size of the rotating image of the virtual hologram. Watching through this window, observers’ eyes are positioned to accept the holographic image light field because the system tilts the virtual hologram plane relative to the rotational axis. To enhance the viewing experience the team hopes to design a system in which observers can see 3.2-inch holographic 3-D images floating on the surface of the parabolic mirror system at a rate of 20 frames per second.
Test results of the system using a 3-D model and computer-generated holograms were promising — though right now still in a monochrome green color. Next, the team wants to produce a full-color experience and resolve issues related to undesirable aberration and brightness mismatch among the four digital micromirror devices used in the display.
“We are developing another version of our system to solve those issues and expect to have the next model in the near future, including enhancement of the color expression,” said Lim. “Many people expect that high quality holograms will entertain them in the near future because visualizations are increasingly sophisticated and highly imaginative due to the use of computer-aided graphics and recently-developed digital devices that provide augmented or virtual reality.”
And the Princess Leia hologram? That old miniature was a motivating experience of their work, Lim explained.
Scientists working at Korea University, Korea, and TU Berlin, Germany have developed a brain-computer control interface for a lower limb exoskeleton by decoding specific signals from within the user’s brain.
Using an electroencephalogram (EEG) cap, the system allows users to move forwards, turn left and right, sit and stand simply by staring at one of five flickering light emitting diodes (LEDs).
The results are published today (Tuesday 18th August) in the Journal of Neural Engineering.
Each of the five LEDs flickers at a different frequency, and when the user focusses their attention on a specific LED this frequency is reflected within the EEG readout. This signal is identified and used to control the exoskeleton.
A key problem has been separating these precise brain signals from those associated with other brain activity, and the highly artificial signals generated by the exoskeleton.
“Exoskeletons create lots of electrical ‘noise’” explains Klaus Muller, an author on the paper. “The EEG signal gets buried under all this noise – but our system is able to separate not only the EEG signal, but the frequency of the flickering LED within this signal.”
Although the paper reports tests on healthy individuals, the system has the potential to aid sick or disabled people.
“People with amyotrophic lateral sclerosis (ALS) [motor neuron disease], or high spinal cord injuries face difficulties communicating or using their limbs” continues Muller. “Decoding what they intend from their brain signals could offer means to communicate and walk again.”
The control system could serve as a technically simple and feasible add-on to other devices, with EEG caps and hardware now emerging on the consumer market.
Korea University (Hangul: 고려대학교; hanja: 高麗大學校; RR: Goryeo Daehakgyo) is a private research university located in Seoul, South Korea.
It was established in 1905, making it the oldest institution of higher education in South Korea. The student body consists of over 20,000 undergraduate students and 5,000 graduate students. The university’s academic breadth is extensive with its 81 departments in 19 colleges and divisions, and 18 graduate schools and it has over 1,500 full-time faculty members with over 95% of them holding Ph. D. or equivalent qualification in their field. The Korea University Alumni Association consists of more than 280,000 university graduates.
Korea University is a research institution consisting of sixteen undergraduate colleges and twenty graduate divisions. The university is notable in South Korean history for being the first educational institution to offer academic programs in various disciplines, such as law, economics, and journalism. Korea University is particularly well known for its College of Law, which is widely considered to be one of the most prestigious undergraduate law programs in South Korea. Korea University also has auxiliary educational facilities such as the Institute of Foreign Language Studies, the Institute for Continuing Education, the Institute of International Education, and the Center for Teaching and Learning. There are 115 research institutes, including the [email protected] Laboratory, the Ilmin International Relations Institute, and the Center for Information Security Technologies.
The Latest Updated Research News:
Korea University research articles from Innovation Toronto
- A brain-computer interface for controlling an exoskeleton – August 19, 2015
- Experts close to perfect in determining truth in interrogations using active question methods – August 21, 2014
- Supersonic spray delivers high-quality graphene layer at low cost – May 30, 2014
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