SSiz mean exp+tab

StatTools : Sample Size for Estimating Population Mean Explanations and Table

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This page provides a table for samples size needed to establish the value of population mean. The table consists of 5 columns.

The first (in bold) is the ratio of the tolerable error and the expected Standard Deviation of the population. To put in in another way, the tolerable error in Standard Deviation (z) units.
The seconf to the fifth column are the sample size required for estimating population means to 90%, 95%, 99%, and 99,5% Confidence Intervals
For example, to have 95% confidence interval that the mean will fall within the range of ± a fifth of the expected Standard Deviation (ER/SD=0.20), the sample size required is 99

ER/SD	Sample Size				ER/SD	Sample Size
	CI=90%	CI=95%	CI=99%	CI=99.5%		CI=90%	CI=95%	CI=99%	CI=99.5%
0.02	6789	9620	16624	19604	0.04	1701	2404	4142	4922
0.06	754	1066	1847	2189	0.08	425	602	1042	1237
0.1	272	386	666	793	0.12	190	269	464	551
0.14	141	199	342	407	0.16	107	153	263	312
0.18	87	121	209	248	0.2	70	99	170	201
0.22	58	82	141	167	0.24	48	70	119	141
0.26	43	60	102	121	0.28	38	53	89	105
0.3	33	45	77	92	0.32	28	40	68	82
0.34	25	35	63	73	0.36	23	33	55	65
0.38	20	30	50	59	0.4	18	28	45	53
0.42	18	25	43	50	0.44	15	23	38	45
0.46	15	20	35	43	0.48	13	20	33	38
0.5	13	18	30	35	0.52	13	18	28	33
0.54	13	15	28	33	0.56	10	15	25	30
0.58	10	13	23	28	0.6	10	13	23	28
0.62	8	13	23	25	0.64	8	13	20	23
0.66	8	13	20	23	0.68	8	10	18	23
0.7	8	10	18	20	0.72	8	10	18	20
0.74	8	10	15	18	0.76	8	10	15	18
0.78	8	8	15	18	0.8	8	8	15	18
0.82	8	8	13	18	0.84	5	8	13	15
0.86	5	8	13	15	0.88	5	8	13	15
0.9	5	8	13	15	0.92	5	8	13	13
0.94	5	8	13	13	0.96	5	8	10	13
0.98	5	8	10	13