Question

The Lung Capacity data

Several variables are recorded on individuals in a medical clinic, one of which is their lung capacity. The variables in this data set are:

            Gender (Male, Female)

            Age (in years)

            Height (inches)

            Weight (pounds)

            Chest (circumference, in inches)

            Waist (circumference, in inches)

            Activity (level, Light, Moderate, Heavy)

            Smoke (Yes, No)

            Capacity (lung capacity, in liters)

You will not need to open the data file in order to answer the questions below.

For each of the following situations, state whether the proper interval would be a confidence interval or a prediction interval. You don’t have to actually provide the interval! But you do have to provide a brief justification for your choice.

a)   We wish to estimate the lung capacity for an individual who is 70 inches tall.

b)   We wish to estimate the average lung capacity for individuals with chest circumference 40 inches.

c)   We wish to estimate the mean lung capacity for individuals who weigh 165 pounds.

d)   We wish to estimate the lung capacity for a woman who is 68 inches tall.

Answer 1

(a) Here a prediction interval wouldl be more proper interval as we are estimating the lung capacity of particular (single) individual having a particular feature (i.e. height)

(b) Here a confidence interval would be more proper interval as we are estimating an aveage lung capacity for a group of indiviuals having a particular feature i.e.chest circuference.

(c) Here a confidence interval would be more proper interval as we are estimating an mean lung capacity for a group of indiviuals having a particular feature i.e.weight.

(d) Here a prediction interval wouldl be more proper interval as we are estimating the lung capacity of particular (single) individual having a particular feature (i.e. height)