Data and Measurement Flashcards
1
Q
Accuracy
A
- how close the measurement is to its true value
2
Q
Precision
A
- how close a set of measurements are to each other
3
Q
Repeatability
A
- how close results will be if the experiment is replicated under the same conditions
4
Q
Reproducability
A
- how close the results will be to each other if the experiment is replicated under different conditions
5
Q
True Value
A
- the value of the measurement if it could be measured perfectly
6
Q
Quantitative Data
(3)
A
- uses numbers
e.g. figures, statistics - usually objective
7
Q
Qualitative Data
(3)
A
- uses words
e.g. anecdotes, opinion - usually subjective
8
Q
Internal Validity
(2)
A
- the extent to which the investigation actually investigates what it sets out/or claims to investigate
- improved by controlling extraneous variables, counterbalancing, validly operationalising variables
9
Q
External Validity
A
- the generalisability of the results to real-world settings
- improved by conducting the experiment in natural settings
10
Q
Standard Deviation
(3)
A
- how far the scores are spread out from the mean
high s.d = high variation = low precision
low s.d = low variation = high precision
11
Q
Error
A
- difference between the true value and the measured value
12
Q
Outliers
A
- scores which are extremely different from the rest
- may occur by random errors (chance)
13
Q
Uncertainty
A
lack of exact knowledge of the value of the quantity measured
14
Q
Random Error
(5) (chance)
A
- affect precision
- unpredictable
- results in spread of reading
- caused by limitation of instruments, environmental factors
- reduced by repeating measurements and calculating new mean, increasing sample size
15
Q
Systematic Errors
(4) (constant)
A
- affect accuracy
- differs measurement from true value by constant amount each time
- caused by observational errors, imperfect instrument calibration
- reduced by familiarity and experience with instruments
16
Q
Extraneous Variable
(4)
A
- variable other than the IV or DV that may cause a change in the DV and therefore may affect results in an unwanted way
- if left uncontrolled may become confounding variable
- threatens internal validity
17
Q
Confounding Variable
(3)
A
- variable that is not the IV/DV that has affected the DV and has effects that is indistinguishable from the IV’s effects thereby providing an alternate explanation for the results
- may have been an uncontrolled/cannot be controlled extraneous variable
- threatens internal validity
18
Q
Placebo Effect
(2)
A
- participants expectations on how to behave
- controlled by single blind (usually with placebo treatment)
19
Q
Experimenter Effect
(2)
A
- experimenter biasing interaction with participants/interpretation of results to be congruent with their hypothesis
- controlled by double blind
20
Q
Social Desiribility Bias
(2)
A
- over-report/exhibit socially desirable characteristics/behaviours
- under-report/inhibit socially undesirable characteristics/behaviours
21
Q
Uncertainty
A
lack of exact knowledge of the value of the quantity measured
