Question

For a physiology class experiment, a student is fitted with a lightweight waterproof device that measures her average pulse rate over 2-hourly intervals. Consider 12 consecutive intervals over a 24-hour period, and let X be the number of these intervals in which the average pulse rate is less than 100 beats per minute. Is it reasonable to treat X as an observation from a binomial distribution? Justify your answer

Answer 1

Number of trials,that is number of intervals, are fixed to 12. The number of outcomes in each trials: pulse rate is less than 100 or pulse rate is not less than 100

The probability that pulse rate will be less than 100 is not given. Logically it may change for each trial. Therefore we cannot assume that probability of success is constant for each trial.

So, it cannot be modeled as binomial distribution.

Answer: It is not reasonable to treat X as an observation from a binomial distribution.