Table:
behaviour
beta
p-value

screen time
0.128
0.0002

sedentary time

total
0.124
0.0016

weekday
0.079
0.0309

weekend
0.170
0.0003

lpa

total
0.096
0.0001

weekday
0.067
0.0030

weekend
0.103
0.0003

mvpa

total
0.002
0.0070

weekday
0.002
0.0134

weekend
0.002
0.0432

In tables, merged cells are often found and we can denote them as JSON {'top-left':(x, y), 'bottom-right':(z, w)}, with '(x, y)' and '(z, w)' indicating the (row_id, column_id) of the top-left and bottom-right cells of the merged region. Please scan the table image provided, find all occurrences of merged cells, and return their coordinates in the stated format. It's important to remember that row and column IDs begin from 1.

The merged cell areas are as follows:
{'top-left':(3, 2), 'bottom-right':(3, 3)}
{'top-left':(7, 2), 'bottom-right':(7, 3)}
{'top-left':(11, 2), 'bottom-right':(11, 3)}.