HP 12C Mean, Standard Deviation, Standard Error for Grouped Data

1.Press CLEAR .

2.If you are summing one set of numbers, key in the first number and press

. Continue until you have entered all of the values.

3.If you are summing two sets of numbers, key in the y-value and press

, key in the x-value and press . Continue until you have entered all of the values.

4.Press to obtain the mean of the x-values.

5.Press 1 to obtain the standard error of the mean of the x-values.

6.Alternatively, press 1 to obtain the standard error for the mean of the y-values.

Example: A sample of 6 one-bedroom apartment rentals reveals that one rents for $190 per month unfurnished, one rents for $200 pre month, two rent for $205 per month, one rents for $216 per month, and one rents for $220 per month. What are the mean monthly rental and the standard deviation? What is the standard error of the mean?

	Keystrokes		Display
	CLEAR
190	200		6.00	Total number of inputs.
205	205	216
220
			206.00	Average monthly rent.
			10.86	Standard deviation.
	1		4.43	Standard error of the mean.

Mean, Standard Deviation, Standard Error for Grouped Data

Grouped data are presented in frequency distributions to save time and effort in writing down (or entering) each observation individually. Given a set of data points

x1, x2, ... , xn

with respective frequencies

f1, f2, ... , fn

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