Researchers have tested many persuasion strategies, including the foot-in-the door and the door-in-the-face techniques, in a variety of contexts. Ultimately, the principles are effective in selling products and changing people’s attitude, ideas, and behaviors (Cialdini & Goldstein, 2004).

The deviations show how spread out the data are about the mean. A positive deviation occurs when the data value exceeds the mean, whereas a negative deviation occurs when the data value is less than the mean. If the deviations are added, the sum is always zero. So one cannot simply add the deviations to get the data spread. By squaring the deviations, the numbers are made positive; thus, their sum will also be positive.The standard deviation measures the spread in the same units as the data.

Abraham Maslow, a prominent figure in humanistic psychology, developed a theory centered on self-actualization, which he placed at the top of his hierarchy of needs. According to Maslow, self-actualization represents achieving one's full potential and is a rare accomplishment attained by approximately 2% of the population. Maslow identified notable historical figures such as Thomas Jefferson, Mahatma Gandhi, Helen Keller, and Martin Luther King Jr. as examples of self-actualized individuals.

Person perception is influenced by both external behaviors and the observer’s internal characteristics, including personality traits. Individuals with dark personality traits, comprising psychopathy, Machiavellianism, and narcissism — collectively known as the dark triad – exhibit manipulative and exploitative tendencies in social contexts. These traits affect how they perceive others and how they are perceived.The Role of Dark Personality Traits in Person PerceptionBlack et al. (2014) explored...

Self-serving bias is a cognitive phenomenon in which individuals attribute positive outcomes to internal factors such as their abilities, intelligence, or effort while attributing negative outcomes to external circumstances. This cognitive distortion helps maintain self-esteem but can also impede objective self-assessment.Theoretical Explanations of Self-Serving BiasTwo primary theories explain the self-serving bias: the cognitive explanation and the motivational explanation.The cognitive...

Cognitive bias results from limitations in thinking and information processing, leading to systematic errors in judgment. Conversely, motivational bias stems from personal desires or emotions, causing distortions in perception to align with self-interest. Motivational bias influences how individuals perceive and attribute causes to events, often shaped by personal needs, goals, and self-esteem preservation. This bias can distort judgment, leading to inaccurate assessments of success, failure,...