Answer:
The effect on Assets, Liabilities, owners equity if rent revenue is recorded for this year, but was actually for next year.
Effect due to Error
Journal Entry for Rent (Assuming cash received against advanced rent)
Dr. Cash $XXX
Cr. Rent Revenue $XXX
Revenue has been recorded instead the short term liability. Due to this transaction Equity increased and Liability is decrease. Cash entry is accurate it has no effect due to mistake.
Effect due to Rectification
Rectification entry
Dr. Rent Revenue $XXX
Cr. Unearned Rent income $XXX
This will reduce the revenue which will ultimately reduce the equity value in balance sheet and Increase the liability value, cash has already been recorded correctly.