We explored the influence of this semantic factor on two STM tasks: The role of long-term knowledge in serial recall no lon-ger needs to be demonstrated. However, although the lexi-cal factors that affect immediate serial recall performance have already been clearly identified and examined in a large number of studies e.
About I am a Asst. Professor at Michigan Technological University. This includes studying crossword puzzle playersaerial search and rescue and methods for modeling shared knowledge, and techniques for measuring and modeling the impacte of physiological stressors on cognitive abilities.
Before that, I was a postdoctoral researcher Prof. I obtained my doctoral degree in the Cognition and Perception program of the University of Michigan's Psychology Department.
I graduated summa cum laud from Drew University with degrees in Mathematics and Psychology. Research Interests I study the human cognitive, perceptual, and memory systems using empirical, computational, mathematical, and statistical techniques. My primary research interest is in developing models of how human memory systems represent knowledge, and how people use that knowledge to accomplish tasks.
This ranges from low-level representations of the perceptual systems to high-level decisions made on the basis of expert knowledge.
Decision Theory Recognition-based Decision Making. Much research on decision theory is about choice and option comparison. But in naturalistic situations, developing a course of action is often intuitive and based on recognizing flexible plans that have worked in the past.
In order to better understand these processes, I have developed the The Bayesian Recognitional Decision Model BRDMa computational model of recognition-primed decision making that combines some of my past work on recognition memory with theories of naturalistic decision making.
BRDM is used to account for how experts make decisions based on cues in the environment and their episodic memory and semantic knowledge. Standard implementations of signal detection theory attributes all noise to perceptual processes. The DNM illustrates how inconsistencies in the response can produce ROC functions that violate the assumptions of SDT, but that others have argued point out a fundamental inadequacy of that theory.
This claim led to a published critique of our paper which we responded to here.
The paper also introduces and discusses a novel ROC analysis we called the DS-ROC function that can help measure the influence of perceptual processes in signal detection tasks.
DS-ROC can be a useful way to make an ROC function when you have measureable noise in the stimulus, but want to avoid the problems and complications with confidence ratings.
Non-parametric measures of decision sensitivity. Standard measures of sensitivity and bias in signal detection theory rely on assumptions about signal and noise distributions.
As an alternative, researchers have sometimes used the 'non-parametric' measure A' a-primewhich does not rely on the same types of distribution-based assumptions.
Yet even though A' is commonly used, it does not measure what most people using it have claimed it measures which is the average between the minimum and maximum ROC functions that can pass through a point.
I have helped publish a correction to the formula for A' called Aas well as a related measure of response bias. Some further results were published here. A spreadsheet that can be used to compute A More information by clicking Choice models incorporating perceivability, bias, and similarity.
Luce's choice theory offers a popular alternative to Signal Detection Theory, but unlike SDT which incorporates bias and sensitivity, when choice theory is applied to confusion data, it typically incorporates only bias and similarity, ignoring sensitivity or "perceivability" as a distinct concept.
This is somewhat remarkable, and probably stems mostly from the inability of the estimation models to fit independent measures of similarity, bias, and percievability. I have an in-progress paper examining this issue, which uses variable selection methods to estimate the three conceptual variables for the same data set, in the context of visual letter similarity.
The graph on the right shows data from that paper, which illustrates the need to consider perceivability and similarity separately. Cultural modeling Identifying Cultural ConsensusOne prominent view of culture is that it is the set of shared beliefs, attitudes, and mental models that people living in a shared context develop.
The question then becomes how you identify which beliefs are shared, in order to identify whether there is indeed shared culture. This problem has been addressed previously in the form of Batchelder's Cultural Consensus Theory, which is a true innovation in anthropological methods, but not without its limitations.
In response to some of its liitations, I have developed Cultural Mixture Modelinga method using finite mixture models and E-M optimization to identify cultural consensus, and to identify whether multiple cultures of belief exist within a single population.
Nhe image on the right shows one application of CMM in the context of the Afrobarometer survey, which identified three basice pan-african cultural group views on democracy, with different distributions across nations. The role of consistent knowledge in cultural transmission Much research on the transmission of culture takes the form of agent-based simulations.These effects of phonological-word neighborhood on memory performance suggest that phonological information in long-term memory plays an active role in recall in short-term-memory tasks, and they present a challenge to current theories of short-term memory.
Word-frequency and phonological-neighborhood effects on verbal short-term memory. (). Word-frequency effects on short-term memory tasks: Evidence . Verbal errors (or more commonly: slips of the tongue) have since been titled Freudian slips.
These are errors in speech (or memory and physical action) that are said to occur due to the interference of an unconscious wish, need, or thought. Memory consolidation is the transformation of short-term memories to long-term memories, which is crucial in the acquisition of new ideas.
Until they can be stored more permanently, these memories are temporarily kept in the hippocampus in a process known as Standard Consolidation Theory. Memory for familiar and unfamiliar words: Evidence for a long-term memory contribution to short-term memory span.
D.. F. We believe that the effect of frequency on short-term memory span is due to differences in the accessibility of these phonological representations in long-term memory.
The phonological verbal fluency test can act as a fast screening test to detect cognitive deficits in neurological conditions.
In the present study, its utility in the detection of executive deficits in patients with early Parkinson's disease is demonstrated.