UNIT 1: Scientific Method

Question 1

Independent Variable

Answer 1

The factor that is manipulated in an experiment.
- Always on the x-axis

Question 2

Dependent Variable

Answer 2

The factor that is measured based on how it is changed by the independent variable
- Always on the Y-Axis

Question 3

Positive Control Group

Answer 3

A group that is not expose to the experimental treatment, or Independent Variable, but is exposed to a treatment known to produce a known result.

Used to tell if an experiment is working.

Question 4

Negative Control Group

Answer 4

A group that is not exposed to any treatment, nothing is expected to happen.

May receive a placebo to avoid psychological effects.

Question 5

Experimental group

Answer 5

The group given treatment.

Question 6

Standard Deviation

Answer 6

How close the data is to the mean.

Question 7

Low Standard Deviation

Answer 7

Data is closer to the mean and there is a greater likelihood that the independent variable is causing the changes to the dependent variable.

Question 8

High Standard Deviation

Answer 8

Data is spread out from the mean and it is more likely that other factors are affecting the dependent variable other than just the manipulated variable.

Question 9

Hypothesis

Answer 9

Predictions that can be tested by recording data from observations and experiments.

“If_______, then____________, because_____________________________________________.”

Question 10

Null Hypothesis(H0)

Answer 10

An instance where the researcher tries to disprove, nullify, or reject an idea by stating that there is no difference between two groups of data, and that experimental observations are due to change.

Ex: Tylenol will have no effect on headache relief

Question 11

Alternative Hypothesis

Answer 11

After the null, list all the other possible hypotheses.

(H1, H2, H3, etc…)

EX:
- H1: Tylenol will relive headaches
- H2: Tylenol will not relive headaches

Question 12

Constants

Answer 12

All the factors that stay the same between all groups in an experiment.

Question 13

Qualitative Data

Answer 13

Observations with senses

Question 14

Quantitative Data

Answer 14

Observations measured with instruments / numbers

Question 15

Mode

Answer 15

Value that appears the most

Question 16

Median

Answer 16

The middle number in a range of data points.

Question 17

Mean

Answer 17

Average

Question 18

1 Standard Deviation

Answer 18

68% of the data

Question 19

2 Standard Deviations

Answer 19

95% of the data (Most common)

Question 20

3 Standard Deviations

Answer 20

99% of the data

Question 21

Standard Error of the Mean

Answer 21

How well the mean of the sample represents the true mean of the population.

Question 22

Error Bars

Answer 22

Bars drawn usually (+/- 2) standard errors.

• Smaller Error bars are better
• If error bars overlap, the difference is not significant.
• If error bars do not overlap, the difference may be significant.

Question 23

Low Standard Error

Answer 23

Increase in confidence

• Small error bars