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Exercise

Calculating confidence intervals

Now you will calculate the confidence intervals for the A/B test results.

The four values that have been calculated previously have been loaded for you (cont_conv, test_conv, test_size, cont_size) as variables with those names.

Instructions
100 XP
  • Calculate the mean of the distribution of our lift by subtracting cont_conv from test_conv.
  • Calculate the variance of our lift distribution by completing the calculation. You must complete the control portion of the variance.
  • Find the standard deviation of our lift distribution by taking the square root of the lift_variance
  • Find the confidence bounds for our A/B test with a value equal to our lift_mean, a 0.95 confidence level, and our calculated lift_sd. Pass the arguments in that order.