Jake is interested to know whether rats will learn to run a maze more quickly if they are rewarded each time they make a correct turn or punished every time they make a wrong turn. He randomly allocates 5 lab rats to each condition and trains them up over several days.

Group 1: every time they turn the correct way he gives them a food treat

Group 2: every wrong turn results in a mild electric shock.

After 3 days of training he drops the rats into the maze and times how quickly they are able to run the maze.

A table to show the time taken (seconds) to run a maze by lab rats who have been either rewarded or punished during their training sessions

Group 1 : rewarded for every correct turn with food	Group 2 : punished for every wrong turn with a shock
34	45
28	38
25	39
21	35
18	44

Work out the standard deviation for group 2 (4)

Space for workings:

 

 

 

Standard deviation for group 2 to 2 dp: …………………………………………………..