# CASIO

User´s Guide

## Standard Deviation (SD)

Use the key to enter the SD Mode when you want to perform statistical calculations using standard deviation.

• (SD)

In the SD Mode and REG Mode, the key operates as the key.

fx-82MS/fx-85MS/fx-300MS/fx-350MS: Always start data input with (CLR)(Scl) to clear statistical memory.
fx-220 PLUS: Always start data input with (Scl) to clear statistical memory.

Input data using the key sequence shown below.

<x-data>

Input data is used to calculate values for n, Σx, Σx2, x-, σn and sx, which you can recall using the key operations noted nearby.

To recall Σx2 this type of value: Perform this key operation: fx-82MS/fx-85MS/ fx-300MS/fx-350MS fx-220 PLUS (S-SUM)(Σx2) (Σx2) (S-SUM)(Σx) (Σx) (S-SUM)(n) (n) (S-VAR)(x-) (x-) (S-VAR)(σx) (σx) (S-VAR)(sx) (sx)

Example: To calculate sx, σx, x-, n, Σx, and Σx2 for the following data : 55, 54, 51, 55, 53, 53, 54, 52
fx-82MS/fx-85MS/fx-300MS/fx-350MS:

• In the SD Mode:
(CLR)(Scl)(Stat clear)

55

Each time you press to register your input, the number of data input up to that point is indicated on the display (n value).

545155535452

Sample Standard Deviation (sx) = 1.407885953

• (S-VAR)(sx)
• 1.407885953

Population Standard Deviation (σx) = 1.316956719

• (S-VAR)(σx)
• 1.316956719

Arithmetic Mean (x-) = 53.375

• (S-VAR)(x-)
• 53.375

Number of Data (n) = 8

• (S-SUM)(n)
• 8.

Sum of Values (Σx) = 427

• (S-SUM)x)
• 427.

Sum of Squares of Values (Σx2) = 22805

• (S-SUM)x2)
• 22805.

fx-220 PLUS:

• In the SD Mode:
(Scl)(Stat clear)

55

Each time you press to register your input, the number of data input up to that point is indicated on the display (n value).

545155535452

Sample Standard Deviation (sx) = 1.407885953

• (sx)
• 1.407885953

Population Standard Deviation (σx) = 1.316956719

• (σx)
• 1.316956719

Arithmetic Mean (x-) = 53.375

• (x-)
• 53.375

Number of Data (n) = 8

• (n)
• 8.

Sum of Values (Σx) = 427

• x)
• 427.

Sum of Squares of Values (Σx2) = 22805

• x2)
• 22805.

Data Input Precautions

inputs the same data twice.

fx-82MS/fx-85MS/fx-300MS/fx-350MS: You can also input multiple entries of the same data using (;). To input the data 110 ten times, for example, press 110(;) 10.
fx-220 PLUS: You can also input multiple entries of the same data using (;). To input the data 110 ten times, for example, press 110(;) 10.

You can perform the above key operations in any order, and not necessarily that shown above.

While inputting data or after inputting data is complete, you can use the and keys to scroll through data you have input. If you input multiple entries of the same data using (;) ((;) on the fx-220 PLUS) to specify the data frequency (number of data items) as described above, scrolling through data shows both the data item and a separate screen for the data frequency (Freq).

You can then edit the displayed data, if you want. Input the new value and then press the key to replace the old value with the new one. This also means that if you want to perform some other operation (calculation, recall of statistical calculation results, etc.), you should always press the key first to exit data display.

Pressing the key instead of after changing a value on the display registers the value you input as a new data item, and leaves the old value as it is.

You can delete a data value displayed using and by pressing (CL). Deleting a data value causes all values following it to be shifted up.

Data values you register are normally stored in calculator memory. The message "Data Full" appears and you will not be able to input any more data if there is no memory left for data storage. If this happens, press the key to display the screen shown below.

Press to exit data input without registering the value you just input.

Press if you want to register the value you just input, without saving it in memory. If you do this, however, you will not be able to display or edit any of the data you have input.

To delete data you have just input, press (CL).

After inputting statistical data in the SD Mode or REG Mode, you will be unable to display or edit individual data items any longer after perform either the following operations.

Changing to another mode

Changing the regression type (Lin, Log, Exp, Pwr, Inv, Quad)