Sharp EL-5230, EL-5250 operation manual T test, x - m t = sx2, Example

Chapter 8: Application Examples

T test

The T-test value is obtained by comparing the mean values of sample data and expected average from sample data. Using the t- distribution table, the

reliability of a mean value can be evaluated.

–

x – m t = ———

sx2

——

n

m = expected mean value estimated by sample data n = the number of samples

–

x = actual mean value of the samples sx = standard deviation of the samples

Example

A’s SHOP sells cookies by package on which it is stated contents are 100 g. Buy 6 sample packages and check if the statement is true.

• Setting an expected mean value as 100 (m = 100 g), a t-test value is obtained. If it is larger than the expected t-value obtained from a t- distribution table (at 5% of risk rate), the estimation is wrong. (In this case, A’s SHOP does not sell honestly.)

		Sample	1	2	3	4	5	6
		grams	102	95	107	93	110	98
1.
		Press b 210to open a window for creating a NEW program.
2.		Type TTEST for the title then press e.
	• A NEW program called ‘TTEST’ will be created.
3.		Enter the program as follows.

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