# Exercise 4

Exercise 4: Uncertainty about probability of 80% decline in 20 years, but relative certainty about 80% decline within 50 years

Type 'Lab3' at the prompt.

Pick dataset 7.

Pick 80% decline in 50 years.

Questions:

1. Any type of confidence interval (frequentist) or credible interval (Bayesian) we might put on mu is going to include 0 (not declining). Similarly the intervals for probability of 80% decline in 50 years will be 0 to 1, indicating we can't say much about the absolute probability of 80% decline in 50 years. Do you think the reasonable conclusion here is that we can't say anything about whether declines are plausible in this population?

Type 'Lab3' at the prompt.

Pick dataset 7.

Pick 80% decline in 50 years.

Questions:

1. Any type of confidence interval (frequentist) or credible interval (Bayesian) we might put on mu is going to include 0 (not declining). Similarly the intervals for probability of 80% decline in 50 years will be 0 to 1, indicating we can't say much about the absolute probability of 80% decline in 50 years. Do you think the reasonable conclusion here is that we can't say anything about whether declines are plausible in this population?

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