5.9 KiB
| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Frequency format hypothesis | 1/3 | https://en.wikipedia.org/wiki/Frequency_format_hypothesis | reference | science, encyclopedia | 2026-05-05T09:59:33.511693+00:00 | kb-cron |
The frequency format hypothesis is the idea that the brain understands and processes information better when presented in frequency formats rather than a numerical or probability format. Thus according to the hypothesis, presenting information as 1 in 5 people rather than 20% leads to better comprehension. The idea was proposed by German scientist Gerd Gigerenzer, after compilation and comparison of data collected between 1976 and 1997.
== Origin ==
=== Automatic encoding === Certain information about one's experience is often stored in the memory using an implicit encoding process. Where did you sit last time in class? Do you say the word hello or charisma more? People are very good at answering such questions without actively thinking about it or not knowing how they got that information in the first place. This was the observation that lead to Hasher and Zacks' 1979 study on frequency. Through their research work, Hasher and Zacks found out that information about frequency is stored without the intention of the person. Also, training and feedback does not increase ability to encode frequency. Frequency information was also found to be continually registered in the memory, regardless of age, ability or motivation. The ability to encode frequency also does not decrease with old age, depression or multiple task requirements. They called this characteristic of the frequency encoding as automatic encoding.
=== Infant study === Another important evidence for the hypothesis came through the study of infants. In one study, 40 newborn infants were tested for their ability to discriminate between 2 dots versus 3 dots and 4 dots versus 6 dots. Even though infants were able to make the discrimination between 2 versus 3 dots, they were not able to distinguish between 4 versus 6 dots. The tested new born infants were only 21 hours to 144 hours old. Similarly in another study, to test whether infants could recognize numerical correspondences, Starkey et al. designed a series of experiments in which 6 to 8 month old infants were shown pairs of either a display of two objects or a display of three objects. While the displays were still visible, infants heard either two or three drumbeats. Measurement of looking time revealed that the infants looked significantly longer toward the display that matched the number of sounds.
=== The contingency rule === Later on, Barbara A. Spellmen from University of Texas describes the performance of humans in determining cause and effects as the contingency rule ΔP, defined as
P = P(E|C) - P(E|~C)
where P(E|C) is the probability of the effect given the presence of the proposed cause and P(E|~C) is the probability of the effect given the absence of the proposed cause. Suppose we wish to evaluate the performance of a fertilizer. If the plants bloomed 15 out of 20 times when the fertilizer was used, and only 5 out of 20 plants bloomed in the absence of the fertilizer. In this case
P(E|C) = 15/20 = 0.75
P(E|~C)= 5/20 = 0.25
ΔP = P(E|C) - P(E|~C)
ΔP = 0.75 - 0.25
= 0.50
The ΔP value as a result is always bound between -1 and 1. Even though the contingency rule is a good model of what humans do in predicting one event causation of another, when it comes to predicting outcomes of events with multiple causes, there exists a large deviation from the contingency rule called the cue-interaction-effect.
=== Cue-interaction-effect === In 1993 Baker Mercer and his team used video games to demonstrate this effect. Each test subject is given the task of helping a tank travel across a mine field using a button that sometimes worked correctly in camouflaging and sometimes did not. As a second cause a spotter plane, a friend or an enemy would sometimes fly over the tank. After 40 trials, the test subjects were asked to evaluate the effectiveness of the camouflage and the plane in helping the tank through the minefield. They were asked to give it a number between -100 and 100.
Mathematically, there are two contingency values possible for the plane: the plane was either irrelevant to tank's success, then ΔP=0(.5/0 condition) and the plane was relevant to the plane's success, ΔP=1 (.5/1 condition). Even though the ΔP for the camouflage in either condition is 0.5, the test subjects evaluated the ΔP of camouflage to be much higher in the .5/0 condition than in the .5/1 condition. The results are shown in table below.
In each case, the test subjects are very good in noticing when two events occur together. When the plane is relevant to the camouflage success, they mark the camouflage success high and when the plane doesn't affect the camouflage's success, they mark the camouflage's success value low.
=== Gigerenzer contributions === Several experiments have been performed that shows that ordinary and sometimes skilled people make basic probabilistic fallacies, especially in the case of Bayesian inference quizzes. Gigerenzer claims that the observed errors are consistent with the way we acquired mathematical abilities during the course of human evolution. Gigerenzer argues that the problem with these quizzes is the way the information is presented. During these quizzes the information is presented in percentages. Gigerenzer argues that presenting information in frequency format would help in solving these puzzles accurately. He argues that evolutionary the brain physiologically evolved to understand frequency information better than probability information. Thus if the Bayesian quizzes were asked in frequency format, then test subjects would be better at it. Gigerenzer calls this idea the frequency format hypothesis in his published paper titled "The psychology of good judgment: frequency formats and simple algorithms".
== Supporting arguments ==