# Thread: Expressing a probability of change

1. ## Expressing a probability of change

Hi, my first time posting here but I'm in need of some help with a paper I'm working on. I am using survey data that I have split into deciles.

The proportion of people who move 2 or more deciles between period A and period B in Population 1 is 64%. The size of Population 1 is 5,623.

The proportion of people who move 2 or more deciles between period A and period B in Population 2 is 75%. The size of Population 2 is 6,073.

To give a sense of the different magnitude of change in the two populations I would like to say that "the probability of moving two or more deciles in Population 1 was X, whereas in Population 2 it was Y".

Can anybody help me to find a way to express the probability of moving 2 or more deciles in each population?

Thanks

2. Originally Posted by lmsava
Hi, my first time posting here but I'm in need of some help with a paper I'm working on. I am using survey data that I have split into deciles.

The proportion of people who move 2 or more deciles between period A and period B in Population 1 is 64%. The size of Population 1 is 5,623.

The proportion of people who move 2 or more deciles between period A and period B in Population 2 is 75%. The size of Population 2 is 6,073.

To give a sense of the different magnitude of change in the two populations I would like to say that "the probability of moving two or more deciles in Population 1 was X, whereas in Population 2 it was Y".

Can anybody help me to find a way to express the probability of moving 2 or more deciles in each population?

Thanks
More detail of what you are trying to do please

CB

3. Hi, to add more detail to my first post:

I am trying to calculate the probability of moving from any decile into any other decile that is at least 2 or more deciles upwards from the point of origin. For example, what is the probability of moving upwards from decile 5 to any deciles 7, 8, , 9 or 10.

However, I want to produce an aggregate of that for the whole of the population. So what is the aggregate probability of moving from any origin decile to any destination decile that is 2 or more deciles upwards.

The problem I am having is whether or not to include in my calculation those who cannot move up two or more deciles. For example, it is impossible for people who are in deciles 9 and 10 at point A to move upwards by 2 or more deciles by point B. Should I therefore exlcude them from my calculation of probability of moving upwards?