The valence effect of prediction

Prediction

A prediction or forecast is a statement about the way things will happen in the future, often but not always based on experience or knowledge...

 is the tendency for people to simply overestimate the likelihood of good things happening rather than bad things. Valence

Valence (psychology)

Valence, as used in psychology, especially in discussing emotions, means the intrinsic attractiveness or aversiveness of an event, object, or situation. However, the term is also used to characterize and categorize specific emotions. For example, the emotions popularly referred to as "negative",...

refers to the positive or negative emotion

Emotion

Emotion is a complex psychophysiological experience of an individual's state of mind as interacting with biochemical and environmental influences. In humans, emotion fundamentally involves "physiological arousal, expressive behaviors, and conscious experience." Emotion is associated with mood,...

al charge something has.

This finding has been corroborated by dozens of studies. In one straightforward experiment, all other things being equal, participants assigned a higher probability to picking a card that had a smiling face on its reverse side than one which had a frowning face.

In addition, some have reported a valence effect in attribution

Attributional bias

In psychology, an attributional bias is a cognitive bias that affects the way we determine who or what was responsible for an event or action...

 when we overpredict the likelihood of positive events happening to ourselves relative to others. (See self-serving bias

Self-serving bias

A self-serving bias occurs when people attribute their successes to internal or personal factors but attribute their failures to situational factors beyond their control. The self-serving bias can be seen in the common human tendency to take credit for success but to deny responsibility for failure...

.)

The outcome of valence effects may be called wishful thinking

Wishful thinking

Wishful thinking is the formation of beliefs and making decisions according to what might be pleasing to imagine instead of by appealing to evidence, rationality or reality...

. However, in certain situations, the valence effect may actually alter the event in some way so that it indeed results in a positive outcome. For examples, in some cases generals have roused up

Morale

Morale, also known as esprit de corps when discussing the morale of a group, is an intangible term used to describe the capacity of people to maintain belief in an institution or a goal, or even in oneself and others...

their soldiers to a point where they were able to emerge victorious in battle.