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sample variance

(symbol: s2) the dispersion of scores within a group selected for study, as opposed to the population variance. It is calculated by determining each score’s difference from the average for the set, squaring and summing these differences, and then dividing by the total number of scores minus one.

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Psychology term of the day

March 17th 2025

end plate

end plate

a specialized region of a muscle-cell membrane that faces the terminus of a motor neuron within a neuromuscular junction. The depolarization that is induced in this muscular region when stimulated by a neurotransmitter released from the adjacent motor neuron terminus is called the end-plate potential (EPP). A very small variation in this potential due to the random release of tiny amounts of a neurotransmitter at an axon terminal is called a miniature end-plate potential. Also called motor end plate.