A bit of bedtime reading is a fairly common practice, and researchers examined whether changes in reading technology could impact sleep quality. They recruited a sample of 12 healthy adults to sleep in a sleep lab on two different days. In random order, participants read, for 30 minutes, a print book on one night and a light-emitting e-reader on the other night. Scalp electrodes used to measure how long (in minutes) it took participants to reach a deep sleep stage. On average, the subjects took 12.3 minutes longer to reach deep sleep when they read with the e-reader than when they read with the book. 14 (a) What are the individuals, the treatments, and the response variable in this experiment?
(b) What is the design of this experiment?
(c) Sleeping in an unfamiliar environment can create a sleep disturbance called the first night effect. Explain why it is important to select the print-book and e-reader nights in random order for each participant.

Solution :

a). The researcher in the experiment recruited 12 adults wo are healthy to conduct the study. So the individuals are the "healthy adults".

The treatment is the "reading technology" and the response variable in the experiment is the time taken to get a deep sleep.

b). Here, in this research study every participant are randomly assigned to the treatment, i.e. the e-book or the print book at night. So we can say that a true experimental research design has been made to conduct this experiment.

c). It is very important to select the e-reader night or the print book at random order for the participant in order to reduce bias and also to remove any effect of the confounding variable.

The randomization of the participants means the random assignment of the treatments.

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for

step-by-step explanation:

the true ones are a b and d