I need to transform a fairly large data set in order to analyse a certain variable as a percentage. I have seconds that I want to convert to their percentage value but by grouping variables.
ie. Age/sex category and month
I am working with SPSS and have convinced myself there must be an easy way to do this without having to manually calculate it all in excel. I suspect it will have to do with creating a new variable but for the life of me can not figure it out.
I simply want to compare proportion of time (seconds) spent eating certain plant parts by age/sex categories and months. All the papers I have read compare mean percentages (of time) is there an easy way to calculate this or must i continue to slug away with excel??
- In desperate need :(
This is how the data is structured at present. Each row is a recorded observation of a feeding event the date is in the first 3 columns, plant part, AgeSex category and group are all converted into numerical data.
What I set out to determine is whether there is significant difference in ingestion of certain plant parts and nutrients by age/sex category.
To look at the difference most sources I look at, consider the proportion of time by age/sex in relation to each plant part. I want to also do it by month as it is already well recognised that there is significant change in dietary composition month-month.
So I guess what I am asking is if there is some way to calculate the mean percentage of seconds while applying the required grouping factors?
If this is on the incorrect board still I will figure out how to get it moved. :)