tell application "System Preferences"

    reveal anchor "displaysDisplayTab" of pane "com.apple.preference.displays"

end tell

tell application "System Events"

    tell application process "System Preferences"

        repeat until (exists radio button "Scaled" of radio group 1 of group 1 of window "Displays")

            delay 0.1

        end repeat

        tell window "Displays"

            set isScaled to value of radio button "Scaled" of radio group 1 of group 1

            if isScaled = 0 then

                click radio button "Scaled" of radio group 1 of group 1

                click button 1 of UI element 3 of group 1

            else

                click radio button "Default for display" of radio group 1 of group 1

            end if

        end tell

    end tell

end tell

quit application "System Preferences"