For the selected step and dimension the Bridge shows the Mix effect and the performance effect.
The bridge focuses on one KPI at a time. It shows the impact that each dimension has on the value of the KPI (whilst on the main waterfall the impact is on the overall KPI).
For the selected step and dimension (you can change what’s selected in the slide title) this bridge shows the impact of each segment variation on the step’s global variation. Changes are grouped in Mix effect and Performance effect, or Negative and Positive moves.
Some key elements:
- The percentage is the evolution of the Mix and the Performance effect between Start and End dimension. (e.g.: evolution between last month and current month)
- The unit used for this graph is real unit of the step (e.g. in the picture above, we selected the Checkout/ Sessions step which is our unit for this graph. The performance effect of Organic has a negative impact of -0.00517 on Checkout/ Sessions)
- The Coefficient (e.g. “organic (x2.43)”) The figure in parenthesis explains the acceleration this element has compare to the other element in the dimension. « The fall of the referral traffic goes 2.43 times faster than the other type of medium traffic ». If this figure is close to 1, this will say that the element you’re looking has the same rise or fall than the other element in the dimension. This will tell you that everything is rising or falling at this step and nothing in your dataset explain why this step is positive or negative. You should add some more dimension to explain this variation (weather, holidays, day-off, bank holidays, strike, price versus competition, …)