Shidduch resumes sometimes simply list schools, family members and references. Whenever the shidduch resume has a section "About Me" and "Looking For", descriptions of their personality supposedly tailored specifically for them, are in fact vague and general enough to apply to a wide range of people. This is called the Forer effect (also called the Barnum effect).

In 1948, psychologist Bertram R. Forer gave a personality test to his students. He told his students they were each receiving a unique personality analysis that was based on the test's results and to rate their analysis on how well it applied to themselves. In reality, each received the same sketch.

On average, the students rated its accuracy as 4.26 on a scale of 0 (very poor) to 5 (excellent). Only after the ratings were turned in was it revealed that each student had received identical copies assembled by Forer from a newsstand astrology book.

Self-serving bias

It is not only that the personality descriptions are vague and generic, and not only when the whole spectrum is covered, but also social desirability that causes distortions in personality descriptions. Self-serving bias is found when participants were given a list of generic traits and asked to rate how much they felt these traits applied to them. The majority agreed with positive traits about themselves, and disagreed with negative ones.

Because the self-serving bias distorts cognitive or perceptual processes in order to maintain and enhance self-esteem, it perpetuates illusions and error.

Not only are "shidduch resumes" misleading, reports from references can be giving a wrong picture. Yismach clients were asked whether the references provided accurate information and over 43% said no. Providing references and calling references and others before a date is a relatively new development historically. There is good reason to believe that this is counter-productive.

The Vividness Criterion

The way that a reference describes the one in shidduchim has disproportionate impact on the decision of whether there will be a first date. Specifically, information that is vivid, concrete, and personal has a greater impact on our thinking than pallid, abstract information.

Absence of Proof

Rav Yisrael Gans, Rosh Yeshiva of Kol Torah delineates the parameters of what a reference is allowed to say, stresses the importance of the reference to report what they personally know.

In making a determination of shidduch appropriateness analysis, it is probably more difficult to recognize that important information is absent and to incorporate this fact into judgments on the shidduch.

First impressions

Although some claim they can tell personality traits from facial features, the master's thesis of the Director, Reb (Prof.) Neumann shows the flaws in this. In his study, he took pictures of students in a college who shared a residence for 3 years, then seniors in college. The students rated each other on 20 personality traits. He then showed these pictures to groups of other students who attended a different university which was 40 miles away and each student rated the person in each picture on the same 20 personality traits.

What he found in his thesis (later published in professional journals), was that there was very high reliability quotients in both groups, meaning that there was a great deal of agreement on all 20 personality traits of each person rated. To oversimplify, 9 out of 10 students who rated the person by picture alone agreed and 9 out of 10 of the students who lived together for 3 years agreed. However, there was wide discrepancies in ratings of each trait between the two groups.

First impressions are reliable but not valid.

There is a type of distortion that the shachan can inadvertently induce. This is the observer-expectancy effect (also called the experimenter-expectancy effect, expectancy bias, observer effect, orexperimenter effect) is a form of reactivity in which a researcher's cognitive bias causes them to unconsciously influence the participants of an experiment.

The Shadchan must interview the person from an unbiased position, rather than show the client their own opinions and influence what they will say they are looking for or their description of themselves.

Distinction Bias From Suggesting Multiple Offers

Suggesting multiple suggestions at a time might seem to "level the odds" of success, but counter intuitively, this is not true.

Distinction bias, a concept of decision theory, is the tendency to view two options as more distinctive when evaluating them simultaneously than when evaluating them separately.

Bottom line, less is more. The minhag of giving only one suggestion at a time should be adhered to.

There are more biases and distortions that also distort their reactions to the other in an initial meeting.

Leveling and sharpening are two contrasting automatic functions within our memory. Sharpening is the tendency to retroactively add vivid details in the retelling of self-experienced - and retold stories. Leveling is our tendency to exclude and tone down parts of stories in memory and to fill in memory gaps.

Peak–end rule

A shadchan suggests two people that agree to go out. The first date didn't go well. The shadchan pushes for a second date. This time for the second date they both report back that it was great. However, on the third date, they decide to end it. Confused, the shadchan wonders: what happened?

The peak–end rule is a theory that describes how humans hedonically evaluate past experiences. This heuristic process leads people to judge an experience by its most intense point and its end, as opposed to the total sum or average of every moment of the experience.

Familiarity

Research has demonstrated that familiarity typically promotes attraction, to the point where even mere exposure to a person increases liking. However, at times, mere exposure works in the opposite direction when that additional exposure reveals negative characteristics of the object or person in question.

Proximity

One powerful predictor of whether any two people are friends is sheer proximity. Proximity can also breed hostility; most assaults and murders involve people living close together. But much more often, proximity prompts liking.

Anticipation of Interaction

Proximity enables people to discover commonalities and exchange rewards. But merely anticipating interaction also boosts liking.

Getting past the first two dates the process of getting to know each other begins, getting past first impressions. There are variables that distort thinking even at this stage.

Overgeneralization: The common example of the more general fallacy of basing a conclusion on unrepresentative evidence, it is incorrect to arrive at a general conclusion based on a single incident or piece of evidence.

Polarized Thinking: This is the fallacy of thinking that things are either black or white, good or bad, all or nothing. This fallacy can lead to rigid and harmful rules based on primal thinking.

Catastrophizing: You anticipate an unreasonable disaster based on a small problem. Every scrap of bad news turns into an inevitable tragedy.

Summary: To summarize, our thinking is the result of our own perception, judgment, experience, and bias. Our brain distorts reality to increase our self-esteem through self-justification. During times of stress, overload, or threat, we often resort to a simplistic form of thinking. It is essential to bear in mind that these distortions and biases exist throughout the shidduch process, and prevent suitable shidduchim from actualizing.