What is the Scaling Factor in ARINC 429?
In the example you pasted, the value $1.5_{10}$ is being sent, which has binary representation $1.1_{2}$. The data is sent as an unsigned integer so some kind of multiplier needs to be applied. The value occupies 19 bits, at offset 11 within the packet itself being bit 0 of the data. The default multiplier is such that the "units" bit (ie the one representing $1_{10}$) is in bit 26 in the packet, that is the bit 16 of the value. You can see that in the first example, the lefthand $1_{2}$ is in bit position 16 (counting from 0 from right).

This allows only values up to slightly short of 8. Various scalings are applied to values, depending on the label, as this may not be a convenient range for the data conveyed. If a label conveys data in the range 0-6, then it is fine as is. If 0-65 must be conveyed by a label, then the value is shifted right four places (to give more space for the larger numbers, but with less precision). Which scaling is applied is determined by the label. If a negative number is possible in a type, two's complement is applied. The label definition determines the range of its various words.

You can see this example effectively repeated immediately with value $1.25_{10}$, which is $1.01_{2}$.