Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Expected Value

Expected Value

The expected value is known as the "long-term" average or mean. This means that over the long term of experimenting over and over, you would expect this average. The expected average is represented by the symbol μ. It is calculated as follows:

The Evidence for Evolution

The Evidence for Evolution

Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.

Determination of Expected Frequency

Determination of Expected Frequency

Suppose one wants to test independence between the two variables of a contingency table. The values in the table constitute the observed frequencies of the dataset. But how does one determine the expected frequency of the dataset? One of the important assumptions is that the two variables are independent, which means the variables do not influence each other. For independent variables, the statistical probability of any event involving both variables is calculated by multiplying the individual...

Expected Frequencies in Goodness-of-Fit Tests

Expected Frequencies in Goodness-of-Fit Tests

A goodness-of-fit test is conducted to determine whether the observed frequency values are statistically similar to the frequencies expected for the dataset. Suppose the expected frequencies for a dataset are equal such as when predicting the frequency of any number appearing when casting a die. In that case, the expected frequency is the ratio of the total number of observations (n) to the number of categories (k).

Acid Suppressive Drugs for Peptic Ulcer Disease: Antacids

Acid Suppressive Drugs for Peptic Ulcer Disease: Antacids

In the complex environment of the gastric lumen, excessive acid secretion can lead to the formation or worsening of ulcers within the delicate mucosal layer. Antacids, such as sodium bicarbonate and calcium carbonate, provide relief by neutralizing this acid, transforming it into harmless salt and water. This neutralization process raises the gastric pH from a highly acidic level of 1 to a more basic 3-4, reducing the acidity within the stomach.
However, this neutralization reaction between...

Acid Suppressive Drugs for Peptic Ulcer Disease: Proton Pump Inhibitors

Acid Suppressive Drugs for Peptic Ulcer Disease: Proton Pump Inhibitors

Peptic ulcers, often induced by H. pylori infections or NSAID usage, arise from disruptions in the delicate balance of gastric acid production. Peptic ulcers stem from heightened gastric acid levels due to H. pylori infections or NSAID use. The protective mucus layer diminishes in the presence of these factors, allowing gastric acid to erode the stomach lining and form ulcers.
Gastric acid, a potent cocktail of hydrogen and chloride ions, is produced in specialized parietal cells within the...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Anchor objects guide spatial attention during visual search.

Attention, perception & psychophysics·2025

Same author

Search strategy modulates memory-driven capture.

Attention, perception & psychophysics·2025

Same author

Editorial for Attention, Perception, & Psychophysics.

Attention, perception & psychophysics·2024

Same author

Multisensory processing impacts memory for objects and their sources.

Memory & cognition·2024

Same author

Intermixed levels of visual search difficulty produce asymmetric probability learning.

Attention, perception & psychophysics·2024

Same author

Correction: Object-based attention during scene perception elicits boundary contraction in memory.

Memory & cognition·2024

Same journal

Human thermal sensitivity drifts at extreme temperatures.

Journal of experimental psychology. Human perception and performance·2026

Same journal

Dynamic competition between selective attention and spatial prediction during visual search.

Journal of experimental psychology. Human perception and performance·2026

Same journal

Encapsulation of the visual perception of social events from semantic priming.

Journal of experimental psychology. Human perception and performance·2026

Same journal

Biasmapping: Idiosyncratic covert search in the vicinity of fixation.

Journal of experimental psychology. Human perception and performance·2026

Same journal

What are you still waiting for? Fricative recognition shows encapsulated processing and is partially predicted by secondary cue reliance.

Journal of experimental psychology. Human perception and performance·2026

Same journal

Eye movements reveal that drivers can predict the location of hazards in dynamic road scenes but gaze and awareness are dissociable.

Journal of experimental psychology. Human perception and performance·2026

See all related articles

Search research articles

Related Experiment Video

Updated: Jan 31, 2026

The Measurement and Treatment of Suppression in Amblyopia

The Measurement and Treatment of Suppression in Amblyopia

Published on: December 14, 2012

Evidence for second-order singleton suppression based on probabilistic expectations.

Bo-Yeong Won¹, Mary Kosoyan¹, Joy J Geng¹

¹Center for Mind and Brain, University of California, Davis.

Journal of Experimental Psychology. Human Perception and Performance

|January 1, 2019

Summary

This summary is machine-generated.

Probabilistic expectations of salient distractors, like color singletons, reduce attentional capture. Knowing a distractor is likely to appear helps suppress it, improving search performance.

More Related Videos

Evidence-based Knowledge Synthesis and Hypothesis Validation: Navigating Biomedical Knowledge Bases via Explainable AI and Agentic Systems

Evidence-based Knowledge Synthesis and Hypothesis Validation: Navigating Biomedical Knowledge Bases via Explainable AI and Agentic Systems

Published on: June 13, 2025

Zinc-Sponge Battery Electrodes that Suppress Dendrites

Zinc-Sponge Battery Electrodes that Suppress Dendrites

Published on: September 29, 2020

Related Experiment Videos

Last Updated: Jan 31, 2026

The Measurement and Treatment of Suppression in Amblyopia

The Measurement and Treatment of Suppression in Amblyopia

Published on: December 14, 2012

Evidence-based Knowledge Synthesis and Hypothesis Validation: Navigating Biomedical Knowledge Bases via Explainable AI and Agentic Systems

Evidence-based Knowledge Synthesis and Hypothesis Validation: Navigating Biomedical Knowledge Bases via Explainable AI and Agentic Systems

Published on: June 13, 2025

Zinc-Sponge Battery Electrodes that Suppress Dendrites

Zinc-Sponge Battery Electrodes that Suppress Dendrites

Published on: September 29, 2020

Area of Science:

Cognitive Psychology
Visual Attention

Background:

Salient distractors typically capture attention in visual search.
Little is known about how expectations of distractor occurrence and features influence attentional suppression.

Purpose of the Study:

To investigate how probabilistic expectations of singleton distractor occurrence and color variability affect attentional capture and suppression.
To determine if attention is proactively suppressed for expected distractors.

Main Methods:

Three experiments manipulated the frequency of a color singleton distractor and its color variability.
Response times and saccade targets were measured during visual search.
A probe display measured attention to multiple objects and report accuracy.

Main Results:

Increased expectation of singleton occurrence eliminated response time costs and reduced initial saccades to the distractor.
Expectations of singleton color variability did not affect capture, suggesting suppression of second-order salience.
Proactive suppression of expected singletons was observed, with less frequent reporting of letters in singleton locations.
Singleton repetition priming occurred, but not for specific color or location repetitions.

Conclusions:

Attentional capture by color singletons is attenuated by expectations of their occurrence, not their specific features.
Probabilistic expectations enable proactive suppression of salient distractors, enhancing visual search efficiency.