Keywords

Question 0

Anomalous data

Answer 0

Measurements that fall outside the normal, or expected range of measures values
A large number of readings can help identify anomalies with greater certainty

Question 1

Accuracy

Answer 1

An accurate measurement is one which is close to the true value

Question 2

Calibration

Answer 2

When the equipment has no errors and set to the right scale

Question 3

Causal link

Answer 3

A change in one variable is caused by a change in another variable

Question 4

Confounding variable (control variable)

Answer 4

Affects the outcome of the investigation

Must be kept constant to ensure a fair test

Question 5

Control experiment

Answer 5

An experiment set up to eliminate certain possibilities

So you can compare your data to the control experiment

Question 6

Control group

Answer 6

Group that is treated in exactly the same way as the experimental group except the factor that is being investigated
Allows scientists to make a comparison

Question 7

Correlation

Answer 7

Shows that there is a relationship between two variables, however, it might not be a causal one

Question 8

Dependant variable

Answer 8

The variable that is measured for each change in the independent variable

Question 9

Double-blind trial

Answer 9

Neither the patients nor the scientists know which treatment a particular individual is receiving until after the completion of the trial.
Helps to avoid bias and increase the validity of the trial.

Question 10

Errors

Answer 10

Something that causes readings to be different from the true value

Question 11

Evidence

Answer 11

Data or observations that are used to support a given hypothesis or belief

Question 12

Fair test

Answer 12

One which only the independent variable has been allowed to affect the dependant variable
Can be achieved by keeping all other variables constant or controlled

Question 13

Hypothesis

Answer 13

A possible explanation of a problem that can be tested experimentally

Question 14

Independent variable

Answer 14

The variable that we change

Question 15

Precision

Answer 15

Related to the smallest scale division on the measuring instrument that is being used.
A set of precise measurements will have very little spread about the mean value

Question 16

Protocol

Answer 16

Once an experimental method has been shown to produce valid and reliable results, it becomes a protocol

Question 17

Random distribution

Answer 17

One that arises as a result of chance
The data is collected at random
Avoids observer bias and allows statistical tests to be used in an analysis of the results

Question 18

Random errors

Answer 18

Occur in an unpredictable way

May be caused by human error, faulty technique in taking measurements or by faulty equipment

Question 19

Raw data

Answer 19

Data that you have collected

Used to calculate percentages and standard deviations

Question 20

Reliability

Answer 20

The results can be considered reliable if the can be repeated
Reliability within a single investigation can be improved by carrying out repeat measurements

Question 21

Systematic errors

Answer 21

Errors that causes readings to be spread about some value other than the true value.
Readings are shifted in one direction from the true value.
May occur when using wrongly calibrated instruments

Question 22

True value

Answer 22

Accurate value which would be found if the quantity could be measured without any errors

Question 23

Validity

Answer 23

Data is valid if the measurements are only affected by the independent variable.
Not valid if control variables have changed or if experiment is bias.
Valid conclusion is supported by reliable data measured with appropriated accuracy

Question 24

Zero errors

Answer 24

Caused by instruments that have an incorrect zero.