Question

CONFIDENCE INTERVAL PROJECT – Day 1

For this project, you’ll be calculating a Confidence Interval for both a Proportion and a Mean. You must first choose a theme for your project. Choose something that you are interested in and passionate about.

THEME: ____________________________________

**For this entire project, we are making the population “people you know.” This will allow you to collect data from anyone!

PROPORTION CONFIDENCE INTERVAL:

Think about a proportion that you wish you knew about all of the people that you know. Fill in the following statement relating to your theme:

I wonder what proportion of people that I know ________________________________??

For example: (have red hair)

(are practicing social distancing)

(watched Game of Thrones)

(think Brad Pitt is a good actor)

If you knew the answer to your above question, would it be a statistic or parameter?

(Circle one)

What symbol would represent its value? ________

MEAN CONFIDENCE INTERVAL

This about an average you wish you knew about all of the people that you know. Fill in the following statement relating to your theme:

I wonder what the average _________________________ is of all of the people I know??

For example: (weight)

(number of CDs owned)

(age)

If you knew the answer to your above question, would it be a statistic or parameter?

(Circle one)

What symbol would represent its value? ________

Answer 1

The 'theme' is subjective and I don't consider my choices significant enough to be put down in an answer. Let's proceed with the remaining parts.The main aim of the exercise to understand the difference between a statistic and a parameter:

POPULATION CI:

Assume my choice for the first blank is: I wonder what proportion of people that I know are practicing social distancing.

If I knew the answer to the above question, my answer would have been a PARAMETER. Note, the quantity I am talking about is specific to the population (which is 'all the people I know' in this case), and if I knew the answer (exactly), the knowledge didn't require me to collect a sample and hence it's not a function of a sample, i.e its not a statistic.

Conventionally, 'p' denotes population proportion in statistics.

MEAN CI:

Suppose my choice for the blank is: I wonder what the average weight is of all of the people I know??

If I would have known the answer to that, by a similar argument as above, the answer would correspond to the POPULATION MEAN, which is a PARAMETER.

Conventionally, '' denotes population mean in statistics.