Thank you for your input, Yamin and Proud_Dad!
Proud_Dad, like I previously said, my intention with this question is not to try to crack 11+ problems but to understand the fundamentals of verbal reasoning in general. So, I am not suggesting in any way that you will come across a question like this in any particular test.
And yes, I assumed the same people when I used the word 'researchers' in both statements. Sorry if it wasn't clear.
That's OK, these logical reasoning questions can get quite tricky.
If you had 2 statements like:
1. Politicians believe taxes should be raised.
2. Politicians believe taxes should be lowered.
Then both could be true.
But if you had:
1. David Cameron believes taxes should be raised.
2. David Cameron believes taxes should be lowered.
Then 2 must be false if 1 is true. (lets ignore the fact that there might be more than one person called David Cameron!)