Saved MAT file in the computer is greater than raw .mf4 file

I have MF4 data and when I open the raw MF4 data, save contents into mat file using functions provided by matlab, it is usually greater than my raw data. For example, if raw data is 286 mb, my saved file is more than 350mb. However, if I save the same file in my collugues computer using same steps, it is around 100 mb. I have tried with multiple mf4 files and same problem persists. Any help will be appreciated.

Answer 1

[Walter Roberson]

Check whether you have set your preferences to save to v7.3 mat files. v7.3 can be efficient for plain numeric arrays but they have a lot of overhead for structures.

[anurag purbey]

By default, it is set as version 7.3. Should I change to version 7?

[Walter Roberson]

You can save a dataset with -v7 option, in order to test how much difference it makes for your data