Education Technology

Statistics: Population Mean: σ unknown
by Texas Instruments

Updated on February 18, 2015


Students calculate confidence intervals to estimate the true population mean when the standard deviation of the population is not known.

Key Steps

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    Students will be introduced to the assumptions needed to use the t distribution to estimate the true mean of a population when only the sample mean and standard deviation are known. They will investigate, by graphing, the relationship between a normal distribution and the t distribution.

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    Students are presented with a problem to calculate a confidence interval. They will compute the interval, finding the t-value and the error. Then the teacher will lead students in learning how to use the TInterval command for a second method of finding the interval.

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    As an extension, students are given a data set and asked to construct three confidence intervals. They will be able to use either method from the activity.