The expected numbers (under the null hypothesis) in each cell are equal to. Thus for the introvert/red cell the expected number is. To calculate the chi-squared (c2) statistic the value of. needs to be calculated for each cell in the table.
Ledger Board Definition. A ledger board is a horizontal lumber beam attached to an existing wall and used to tie in construction elements such as porch roofs and decks. A deck ledger is installed as part of the deck frame construction. The frame is then attached at either end, with the deck joists butting up to it.
4. Place the ledger board back against the side of the house and use a spirit level to ensure it is level. Nail the ledger board to the house using three nails -- one at each end and the third in the middle.These nails will hold the ledger board in place while drilling holes for the lag bolts.. Hold the two-by-six ledger board against the side of the house where it will be installed. This is usually a little lower than the threshold of the entry to the house. At a minimum it should be lower by the thickness of the decking so that the deck is not above the threshold.