To the extent that children ...

To the extent that children with similar characteristics achieve comparable performance levels, using the performances of similar peers is likely to yield more accurate self-appraisal than using the accomplishments of dissimilar peers
To the extent that children with similar characteristics achieve comparable performance levels, using the performances of similar peers is likely to yield more accurate self-appraisal than using the accomplishments of dissimilar peers
 Albert Bandura

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Being self-made is a state of mind, and once you put that mentality to work, your success will come.
 Dave East
A lot of people change for good. Some people just fall off. Just trying to progress in anything, no matter what you're doing, I feel like any progression you make... some people aren't gonna be around you that were around you.
 Dave East
There are no secrets to success. It is the result of preparation, hard work, and learning from failure.
You have to have the service mentality in the sense that you subjugate your own ego, and you subjugate a large part of your own life to really helping other people, being successful on their behalf.
 Herb Kelleher
Success consists of going from failure to failure without loss of enthusiasm.

Quotes from the same author

People who believe they have the power to exercise some measure of control over their lives are healthier, more effective and more successful than those who lack faith in their ability to effect changes in their lives.
 Albert Bandura
Perceived self-efficacy also shapes causal thinking. In seeking solutions to difficult problems, those who perceived themselves as highly efficacious are inclined to attribute their failures to insufficient effort, whereas those of comparable skills but lower perceived self-efficacy ascribe their failures to deficient ability
 Albert Bandura
Self efficacious children tend to attribute their successes to ability, but ability attributions affect performance indirectly through perceived self-efficacy
 Albert Bandura
The performances of others are often selected as standards for self-improvement of abilities
 Albert Bandura
For many activities, people cannot rely solely on themselves in evaluating their ability level because such judgments require inferences from probabilistic indicants of talent about which they may have limited knowledge. Self-appraisals are, therefore, partly based on the opinions of others who presumably possess evaluative competence
 Albert Bandura