Question

how does sleep deprivation affect your ability to drive? a recent study measured the effects on 19 professional drivers. each driver participated in two experimental sessions: one after normal sleep and one after 27 hours of total sleep deprivation. the treatments were assigned in random order. in each session, performance was measured on a variety of tasks including a driving simulation.

identify the following characteristics of this experiment.

• response variable
• blinding
• random assignment
• explanatory variable
• experimental units
• control/placebo
• lurking variables
• treatments

a. amount of sleep
b. normal sleep and 27 hours of total sleep deprivation
c. 19 professional drivers
d. none - all drivers participated in both treatments
e. treatments were assigned in random order; this eliminated the effect of any learning that may take place during the first experimental session
f. completing the experimental session under normal sleep conditions
g. performance measured in assigned tasks
h. researchers evaluating subjects’ performance must not know which treatment is being applied at the time

Explanation:

Response variable

The response variable is the outcome being measured. Here, it's the performance in tasks (including driving simulation), so it's g. performance measured in assigned tasks.

Blinding

Blinding involves not letting those involved (like researchers or subjects) know the treatment. Here, researchers not knowing the treatment is h. researchers evaluating subjects’ performance must not know which treatment is being applied at the time.

Random assignment

Random assignment is about assigning treatments randomly. The description here is e. treatments were assigned in random order; this eliminated the effect of any learning that may take place during the first experimental session.

Explanatory variable

The explanatory variable is what's manipulated to see its effect, which is the amount of sleep (a. amount of sleep).

Experimental Units

Experimental units are the subjects, here the 19 professional drivers (c. 19 professional drivers).

Control/Placebo

The control here is the normal sleep condition, so f. completing the experimental session under normal sleep conditions.

Lurking variables

Lurking variables are other variables that might affect the outcome but aren't considered. Since all drivers did both treatments, there's none (d. none - all drivers participated in both treatments).

Treatments

Treatments are the conditions applied, which are normal sleep and 27 - hour sleep deprivation (b. normal sleep and 27 hours of total sleep deprivation).

Answer:

• Response variable: g. performance measured in assigned tasks
• Blinding: h. researchers evaluating subjects’ performance must not know which treatment is being applied at the time
• Random assignment: e. treatments were assigned in random order; this eliminated the effect of any learning that may take place during the first experimental session
• Explanatory variable: a. amount of sleep
• Experimental Units: c. 19 professional drivers
• Control/Placebo: f. completing the experimental session under normal sleep conditions
• Lurking variables: d. none - all drivers participated in both treatments
• Treatments: b. normal sleep and 27 hours of total sleep deprivation