Can you conclude a trend in this data?

#1
I have no experience with statistics at the college level. The survey results below were from a single school, grades 9 - 12. I'm trying to find out if you can conclude a trend exists in the number of students who prefer Product A versus Product B, even though the number of students surveyed at this one school varied year after year. Can you still safely conclude declines in the number of students who prefer Product A & B? I would like to use this data for a report I'm writing but I don't want to overstep. Thanks in advance for any help you can provide. -- Carol


I have no experience with statistics at the college level. The survey results below were from a single school, grades 9 - 12. I'm trying to find out if you can conclude a trend exists in the number of students who prefer Product A versus Product B, even though the number of students surveyed at this one school varied year after year. Can you still safely conclude declines in the number of students who prefer Product A & B? I would like to use this data for a report I'm writing but I don't want to overstep. Thanks in advance for any help you can provide. -- Carol

Years Product A Product B Number of Students Surveyed
1999 15.6% 24.8% (3430)
2000 15.6% 15.7% (3764)
2001 10.1% 12.2% (5240)
2002 11.9% 12.6% (9066)
 

vinux

Dark Knight
#2
I would like to confirm one thing. Is the suvey like
Choose preferred product
1) Product A
2) Product B
3) others

?
 

vinux

Dark Knight
#5
you can safely conclude that there is a declines in the number of students who prefer Products.

But before that you should check the common students in the each year.
I think in each year some percentage of students will leave 12th grade and some percentage may join on 9th grade.so see the percentage gradwise

And
II'm trying to find out if you can conclude a trend exists in the number of students who prefer Product A versus Product B, even though the number of students surveyed at this one school varied year after year.
Relating prod A and prod B may not be appropriate. It is a multinomial setup. ( I assume that a student can't take both the products)

Regards
VINUX