Let's say you collected a sample and calculated characteristics of center and deviation. Imagine you expanded the of your sample and collected data from the whole population. Practically, it's very difficult (almost impossible) to achieve because the size of the population usually is huge. But let's say you obtained the data from the whole population and calculated characteristics for the population. Will they be the same as for the sample? Probably not. Hopefully, they will be not far from the characteristics of the sample. We cannot predict the exact value of the Population characteristics. But with a certain probability (Confidence level) we can predict the interval (Confidence Interval) that will hold Population characteristics. This week's material shows the procedure of estimating Confidence Interval for Population Mean and Population Proportion.

1) Assign any values for sample size, the sample mean, and sample standard deviation. Population standard deviation is unknown

Find Margin of Error and construct Confidence Interval for the Population Mean Use Confidence Level 95%.

2) Do the same as in 1) but with a Confidence Level of 80%.

3) Assign any values for sample size, ample proportion, and estimate Confidence Interval for the Population Proportion. Use Confidence Level 99%. 4) Do the same as in 3) but with a Confidence Level of 90%.