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Statistical Excel 2010 ◉ 8 views

=CONFIDENCE.T()

Returns the confidence interval for a population mean, using a Student's t distribution.

Applies To: Excel for Microsoft 365Excel for Microsoft 365 for MacExcel 2024Excel 2024 for MacExcel 2021Excel 2021 for MacExcel 2019Excel 2016Excel Web App
=CONFIDENCE.T(alpha,standard_dev,size)
Hover argument names in the table for details.
Output typeNumber
Popularity12 / 100
VolatileNo
Dynamic ArrayNo
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◧ Arguments

ArgumentTypeRequiredDescription
alpha Number Required The significance level used to compute the confidence level. The confidence level equals 100*(1 - alpha)%, or in other words, an alpha of 0.05 indicates a 95 percent confidence level.
standard_dev Number Required The population standard deviation for the data range and is assumed to be known.
size Number Required The sample size.

▣ Examples

فاصلهٔ اطمینان میانگین جامعه بر اساس نمونهٔ ‎۵۰تایی با سطح معناداری ‎۵٪ و انحراف معیار ‎۱ بر پایهٔ توزیع t استیودنت =CONFIDENCE.T(0.05,1,50)

✦ Tips

  • If size is not an integer, it is truncated.

⚠ Common Errors

#VALUE! If any argument is nonnumeric, CONFIDENCE.T returns the #VALUE! error value.
Fix: برای هر سه آرگومان مقدار عددی وارد کنید.
#NUM! If alpha ≤ 0 or alpha ≥ 1, CONFIDENCE.T returns the #NUM! error value. If standard_dev ≤ 0, CONFIDENCE.T returns the #NUM! error value.
Fix: Correct the input value
#DIV/0! If size equals 1, CONFIDENCE.T returns #DIV/0! error value.
Fix: حجم نمونه را حداقل ‎۲ وارد کنید، چون با یک نمونه فاصلهٔ اطمینان t قابل محاسبه نیست.

⇄ Related Functions

=STDEV.S() Estimates standard deviation based on a sample (ignores logical values and text in the sample). =CONFIDENCE.NORM() The confidence interval is a range of values. Your sample mean, x, is at the center of this range and the range is x ± CONFIDENCE.NORM. For example, if x is the sample mean of delivery times for products ordered through the mail, x ± CONFIDENCE.NORM is a range of population means. For any population mean, μ0, in this range, the probability of obtaining a sample mean further from μ0 than x is greater than alpha; for any population mean, μ0, not in this range, the probability of obtaining a sample mean further from μ0 than x is less than alpha. In other words, assume that we use x, standard_dev, and size to construct a two-tailed test at significance level alpha of the hypothesis that the population mean is μ0. Then we will not reject that hypothesis if μ0 is in the confidence interval and will reject that hypothesis if μ0 is not in the confidence interval. The confidence interval does not allow us to infer that there is probability 1 – alpha that our next package will take a delivery time that is in the confidence interval. =T.INV.2T() Returns the two-tailed inverse of the Student's t-distribution.

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