Normal Error Curve
- Page ID
- 77468
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If we look at a standardized Gaussian distribution — the so-called Normal Error Curve shown below — you can see that the probability of any one measurement being a member of this particular distribution increases as the magnitude of z increases.
The area underneath the curve represented by "z" multiples of the standard deviation are shown in the table below:
| ±z | Area Represented Under Normal Error Curve (Confidence Level) |
|---|---|
| 1.00 | 68.3% |
| 1.64 | 90.0% |
| 1.96 | 95.0% |
| 2.58 | 99.0% |
| 3.00 | 99.7% |