1. Experimental Design:
The Big 4

2. IV
DV
Control
Constants

3. IV

4. IV
Independent variable

5. IV
Independent variable
Manipulated variable

6. IV
Independent variable
Manipulated variable
the thing “i” change

7. IV
Independent variable
Manipulated variable
the thing “i” change
Example: type of fertilizer

8. IV
in an experiment on the
effectiveness of cleaners, brian
used 4 different types of
cleaner: bleach, windex, vinegar,
and water.

9. IV
in an experiment on the
effectiveness of cleaners, brian
used 4 different types of
cleaner: bleach, windex, vinegar,
and water.

10. DV

11. DV
dependent variable

12. DV
dependent variable
Measured variable

13. DV
dependent variable
Measured variable
The “response” to the change

14. DV
dependent variable
Measured variable
The “response” to the change
example: plant growth

15. DV
in an experiment on the
effectiveness of cleaners, brian
Measured the percentage of
residue remaining after each
cleaner was applied.

16. DV
in an experiment on the
effectiveness of cleaners, brian
Measured the percentage of
residue remaining after each
cleaner was applied.

17. Control

18. Control
used for comparison

19. Control
used for comparison
usually the “most normal” test
group

20. Control
used for comparison
usually the “most normal” test
group
may also be a degree of the iv
with “lowest value”

21. control
in an experiment on the
effectiveness of cleaners, brian
used 4 different types of
cleaner: bleach, windex, vinegar,
and water.

22. control
in an experiment on the
effectiveness of cleaners, brian
used 4 different types of
cleaner: bleach, windex, vinegar,
and water.

23. constants

24. constants
stay the same

25. constants
stay the same
prove the effectiveness of the iv

26. constants
stay the same
prove the effectiveness of the iv
look for values that are held
“constant” for each test group

27. constants
2
brian set up 4-2 in tiles. he labeled the tiles
a,b,c, and d. Each tile was submersed in a 1:1
mixture of motor oil and tar for 30 sec.
they were then allowed to dry for 24 hrs.
brian then poured 50 ml of each cleaner on
the appropriate tile and wiped the tile 1
time from top to bottom with a clean 4 in
sponge.

28. constants
2
brian set up 4-2 in tiles. he labeled the tiles
a,b,c, and d. Each tile was submersed in a 1:1
mixture of motor oil and tar for 30 sec.
they were then allowed to dry for 24 hrs.
brian then poured 50 ml of each cleaner on
the appropriate tile and wiped the tile 1
time from top to bottom with a clean 4 in
sponge.

29. #1 The responding variable in
an experiment is the...
independent variable
dependent variable

30. #1 The responding variable in
an experiment is the...
independent variable
dependent variable

31. #2 the test group that is
used for comparison is the...
control
constant

32. #2 the test group that is
used for comparison is the...
control
constant

33. #3 factors that are kept the
same in an investigation...
controls
constants
variables

34. #3 factors that are kept the
same in an investigation...
controls
constants
variables