Mark Wickens

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SDX / SDY / SDXN / SDYN

[FX-870P/VX-4]

Purpose

Standard deviation functions for statistically processed data.

Format

SDX
SDY
SDXN
SDYN

Example

PRINT SDX
PRINT SDYN

Explanation

Function Returns Formula
SDX Sample standard deviation of X SQR(MEANX2 - MEANX^2)
SDY Sample standard deviation of Y SQR(MEANY2 - MEANY^2)
SDXN Population standard deviation of X SQR(CNT / (CNT - 1)) * SDX
SDYN Population standard deviation of Y SQR(CNT / (CNT - 1)) * SDY
  1. SDX and SDY calculate the sample standard deviation (dividing by N).
  2. SDXN and SDYN apply Bessel’s correction to produce the population standard deviation estimate (dividing by N-1).
  3. SDY, SDYN require paired (X, Y) data to have been entered.
  4. Data must first be entered using the STAT command.

See