Cambridge International AS & A Level

PSYCHOLOGY 9990/23
Paper 2 Research Methods May/June 2024
MARK SCHEME
Maximum Mark: 60

Published

This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the
examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the
details of the discussions that took place at an Examiners’ meeting before marking began, which would have
considered the acceptability of alternative answers.

Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for
Teachers.

Cambridge International will not enter into discussions about these mark schemes.

Cambridge International is publishing the mark schemes for the May/June 2024 series for most
Cambridge IGCSE, Cambridge International A and AS Level and Cambridge Pre-U components, and some
Cambridge O Level components.

This document consists of 20 printed pages.

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Generic Marking Principles

These general marking principles must be applied by all examiners when marking candidate answers. They should be applied alongside the
specific content of the mark scheme or generic level descriptions for a question. Each question paper and mark scheme will also comply with these
marking principles.

GENERIC MARKING PRINCIPLE 1:

Marks must be awarded in line with:

 the specific content of the mark scheme or the generic level descriptors for the question
 the specific skills defined in the mark scheme or in the generic level descriptors for the question
 the standard of response required by a candidate as exemplified by the standardisation scripts.

GENERIC MARKING PRINCIPLE 2:

Marks awarded are always whole marks (not half marks, or other fractions).

GENERIC MARKING PRINCIPLE 3:

Marks must be awarded positively:

 marks are awarded for correct/valid answers, as defined in the mark scheme. However, credit is given for valid answers which go beyond
the scope of the syllabus and mark scheme, referring to your Team Leader as appropriate
 marks are awarded when candidates clearly demonstrate what they know and can do
 marks are not deducted for errors
 marks are not deducted for omissions
 answers should only be judged on the quality of spelling, punctuation and grammar when these features are specifically assessed by the
question as indicated by the mark scheme. The meaning, however, should be unambiguous.

GENERIC MARKING PRINCIPLE 4:

Rules must be applied consistently, e.g. in situations where candidates have not followed instructions or in the application of generic level
descriptors.

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GENERIC MARKING PRINCIPLE 5:

Marks should be awarded using the full range of marks defined in the mark scheme for the question (however; the use of the full mark range may
be limited according to the quality of the candidate responses seen).

GENERIC MARKING PRINCIPLE 6:

Marks awarded are based solely on the requirements as defined in the mark scheme. Marks should not be awarded with grade thresholds or
grade descriptors in mind.

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Social Science-Specific Marking Principles
(for point-based marking)

1 Components using point-based marking:

 Point marking is often used to reward knowledge, understanding and application of skills. We give credit where the candidate’s answer
shows relevant knowledge, understanding and application of skills in answering the question. We do not give credit where the answer
shows confusion.

From this it follows that we:

a DO credit answers which are worded differently from the mark scheme if they clearly convey the same meaning (unless the mark
scheme requires a specific term)
b DO credit alternative answers/examples which are not written in the mark scheme if they are correct
c DO credit answers where candidates give more than one correct answer in one prompt/numbered/scaffolded space where extended
writing is required rather than list-type answers. For example, questions that require n reasons (e.g. State two reasons …).
d DO NOT credit answers simply for using a ‘key term’ unless that is all that is required. (Check for evidence it is understood and not used
wrongly.)
e DO NOT credit answers which are obviously self-contradicting or trying to cover all possibilities
f DO NOT give further credit for what is effectively repetition of a correct point already credited unless the language itself is being tested.
This applies equally to ‘mirror statements’ (i.e. polluted/not polluted).
g DO NOT require spellings to be correct, unless this is part of the test. However spellings of syllabus terms must allow for clear and
unambiguous separation from other syllabus terms with which they may be confused (e.g. Corrasion/Corrosion)

2 Presentation of mark scheme:

 Slashes (/) or the word ‘or’ separate alternative ways of making the same point.
 Semi colons (;) bullet points (•) or figures in brackets (1) separate different points.
 Content in the answer column in brackets is for examiner information/context to clarify the marking but is not required to earn the mark
(except Accounting syllabuses where they indicate negative numbers).

3 Annotation:
 For point marking, ticks can be used to indicate correct answers and crosses can be used to indicate wrong answers. There is no direct
relationship between ticks and marks. Ticks have no defined meaning for levels of response marking.
 For levels of response marking, the level awarded should be annotated on the script.
 Other annotations will be used by examiners as agreed during standardisation, and the meaning will be understood by all examiners
who marked that paper.

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Guide to marking annotations
benefit of doubt correct point [use one tick per incorrect point
mark except in last question use for each point
part (a)] of description of a
required feature
no benefit of doubt indicates a point is a Generic continued in part (a) of last Q
Mark (use ‘link’ icon)

‘something is ? unclear point not answering question

missing’

repetition (of stem/ use wiggly underline/ underline letter-tick when use to show Level
within response) highlighter to bring attention to required feature is in 1, 2, 3, 4 or 5 in
a key part enough detail part (a) of last Q

SEEN acknowledge blank

pages

Important marking guidelines for reference

NR or zero Award No Response (NR):
 if there is nothing written at all in the answer space
 if there is any comment un elated to the question being asked (e.g. ‘can’t do’, ‘don’t know’)
 if there is any sort of mark which isn’t an attempt at the question (e.g. a dash, a question mark).
Note: you can press the # or / key to enter NR
Award Zero (0):
 if there is any attempt that earns no credit, eg the candidate copying all or some of the question, or any working that does not earn
any marks, whether crossed out or not.

Crossed out Please note that if a candidate crosses out a question and does not re-attempt the same question, you must attempt to mark the
work crossed out work.

Annotate Please place a marking icon on every question and to indicate each mark awarded (number of ticks = number of marks on all
every questions except part (a) of the last question). However, you do not need to put ‘seen’ on NR spaces.
question

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Question Answer Marks Guidance

1 Explain what is meant by a covert observation, using 2 Explain covert = 1

any example. Example = 1 (generic or embedded, but not just a
reference)
participants unaware of (role of) observer; (define) Observer does not interact with participants = 0 [this is non-
out of view / far away / disguised / hidden; (example) participant obs]
Bandura used a one-way mirror; (example)
Hassett used a camera; (example)
Piliavin’s observers looked like subway passengers;
(example)

‘In Piliavin the Ps did not know the observers were there’ = 0
= REP

Question Answer Marks Guidance

2 The results from the study by Andrade (doodling) 2 Any descriptive point about the mean = 1
included the following data about the shading of shapes Any descriptive point about the range = 1
by participants in the doodling group: The mean/average doodling was in the bottom half of the
range; (mean)
Outline what these two results show about doodling by All participants in this group doodled; (range)
this group of participants. The variation in doodling was very wide; (range)

 the mean number per participant was 36.3 Statements relating to the non-doodlers = 0 [NAQ]
 the range was 3–110. Comparative statements to controls = 0 [NAQ]
Copying the numbers = 0 [REP]
Conclusions = 0 = NAQ

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Question Answer Marks Guidance

3 Describe how one feature of the study by Milgram 2 Link (feature of study) = 1
(obedience) helped to make the study valid. How it helped validity = 1

 Shock machine looked real; / thought the shocks were Authority figure = 0
real; Authority figure looked real because of coat/of location = 1
 Drawing lots was rigged;
 Grey technician’s coat;
 Location at a university;
 Told it was about memory and punishment (deception);

So participants unlikely to suspect the deception / guess aim

/ respond to demand characteristics; (how)
the prods were the same for all Ps / standardised; (how)

E.g. all Ps heard ‘please continue’; (feature)

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Question Answer Marks Guidance

4 One group of participants in the study by Hölzel et al. 4 Partial explanation = 1

(mindfulness and brain scans) was a sample of 16 right- Full explanation = 2
handed adults: 6 males and 10 females.
Credit answers with other knowledge of the study eg. ages,
Explain two reasons why this sample may not be ethnicity
representative.

Gender bias / more females than males;

So not / less representative of males;

All righthanded;
So not / less representative of lefthanders;

All adults;
So not / less representative of children;

Small sample;
So not much variability;
So not generalisable to ambidextrous people / wide variety
of…; (must be specific)

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Question Answer Marks Guidance

5 Memory research is often conducted using

eyewitnesses who have witnessed a real crime.
Alternatively, researchers can use a simulated crime in a
laboratory and ask participants what they remember.

5(a) One strength of using a simulated crime in a laboratory 2 Outline = 1

is that it can improve objectivity. example must relate to objectivity= 1

Outline what is meant by the term ‘objectivity’, using an an eyewitness seeing a thief stealing something = 0 [NAQ
example about eyewitnesses. not about objectivity]

judgment from external perspective; (outline) If an effective answer is given relating to Pozzulo, credit it.
independent viewpoint; (outline)
data obtained without personal bias; (outline)

researchers might be biased by emotions/suffering of real

eyewitnesses; (example)
in artificial situations, researcher knows the correct memories
of the scene; (e.g.)

5(b) Describe how one feature of the study by Pozzulo et al. 2 Objectivity strategy = 1
(line-ups) helped to make the study objective. How it helped = 1

responses to line-ups limited to present or not; (strategy) silhouettes (as a ‘target absent’ choice); (strategy)
so no ‘maybe’ or ‘more likely to be x than y’; (how it helped) making the choice an objective one between present/absent
participants’ responses were quantitative (present or not); rather than a difficult choice of present /not present; (how it
strategy) helped)
so the researchers did not have to interpret the results; (how
it helped)

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Question Answer Marks Guidance

6 Describe the following experimental designs, using any 6 1 mark per definition/point of detail, max 2 for each
example(s): term/concept.
 matched pairs design 1 mark per example, max 2 for each term/concept.
 repeated measures design. Examples can be any studies (core studies, other studies,
candidate’s own).
Repeated measures: Max 4 if no e.g.s or if only one term/concept.
Same Ps in each level of IV / condition; Only 1 example needed to access 6 marks.
Risk of order effects / practice or fatigue effects;
As Ps see experimental situation more than once;
Also risk of recognising demand characteristics;
Order effects resolved by counterbalancing;
Where half Ps do conditions in order AB, others BA;
eg Dement & Kleitman 5/15 minutes;
Hölzel pre/post mindfulness course;
Perry personal space situations (CIDs) Ps did all of the
different approaching objects (ball, stranger, friend, authority
figure);
Perry different room configurations (of table/chair/plant);

Matched pairs:
Different Ps in each level of the IV;
similar individuals allocated one to each level of IV;
eg one twin in each group;
reducing effects of individual differences;
similarities relevant to study;
e.g. age / IQ / gender;
e.g. similar to Bandura aggression levels of children;

Ps matched into pairs = 0 [REP]design.

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Question Answer Marks Guidance

7 Yashal is planning an experiment about the effect music

has on students doing their homework. She is choosing
the conditions she will use.

7(a) Outline what is meant by the term ‘experimental 1 Outline = 1

condition’.

levels of an independent variable that are actively

manipulated;
two (or more) situations/groups/conditions that compare
levels of an independent variable;

7(b)(i) Outline what is meant by the term ‘control condition’. 1 Outline = 1

situation/group/condition from which the IV is absent; Accept ‘no change to the IV’

Accept ‘a level of the IV where the IV is absent’ Accept: A condition where the IV is absent
Do not accept ‘baseline’ / ‘to compare’ alone

7(b)(ii) Suggest a control condition that Yashal could use in her 1 Example = 1
experiment.

e.g. a no music / no noise / silence group;

e.g. white noise;

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Question Answer Marks Guidance

7(c) Yashal is planning to use students working at home as 2 Type of experiment = 1 Field [definitive]
participants. Explanation (linked) = 1 (may be ‘why it is’ or ‘why it has to
be’)
Explain the type of experiment Yashal would be
conducting.

The students are at home; (explanation)

It’s homework so they won’t be in the controlled situation of
school; (explanation)
The participants are in their normal setting for the activity of
homework;
The participants are in their normal/natural setting = 0 (not
linked)

Question Answer Marks Guidance

8 A parrot rescue centre has some new parrots which

need to learn to enter a cage. Their trainer is planning a
procedure using operant conditioning to teach the
parrots to enter the cage.

8(a) Suggest one way that the parrots could be taught to 3 Way = 1 [can be interpreted in different ways]
enter the cage. Detail = 2
Response must be linked to task for 3 marks
Positive reinforcement; (way) Punish parrots; (way)
Give a reward each time they go into the cage; (detail+link) If they go a different direction; (detail)
Eg food; (detail) E.g. have shock wires under their feet either side of the
route to the cage; (link)
Using food; (way)
To shape behaviour; (detail)
Punish parrots; (way)
For getting closer to the cage; (detail+link)
If they go a different direction; (detail)
operant conditioning = 0 [REP] E.g. have shock wires under their feet either side of the
route to the cage; (link)

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Question Answer Marks Guidance

8(b) The success of the procedure can be measured by

counting the number of days it takes each parrot to learn
to enter the cage.

8(b)(i) Suggest two practical problems with this measurement 4 Limitation = 1} [2]
of success. Either limitation or detail must be linked for 2 marks
1: …. Detail = 1}
2: …. Individual differences between parrots = 0 = NAQ

Learning in 1 minute, 1 hour or 1 day would all look the

same; (linked limitation)
So the data would be invalid (loss of discriminatory power);
(detail)
Parrots may all learn on first day; (linked limitation)
so ceiling effect; (detail)

some parrots may go in then straight out; (linked limitation)

so not a useful measure for aim; (detail)

parrots may focus for various lengths of time; (linked

limitation)
so not all parrots have same amount of training time; (linked
detail)

ethical limitations = 0 [NAQ]

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Question Answer Marks Guidance

8(b)(ii) For one of the problems you suggested in part (b)(i): 2 Way = 1
Detail = 1
Suggest one way this problem could be solved. The prompt (Problem: 1 or 2) should be used. If not clear,
credit if possible
1 min = 1 day / Ceiling effect:
Make interval shorter / avoids a ceiling effect / easier to
distinguish between learning speed / bigger range of scores
is possible; (way)
eg count hours; (detail)

straight out again:

add time limit to ‘enter cage’; (way)
e.g. and ‘stay inside for 30 seconds’; (detail)

parrot focus:
only train in short bouts; (way)
or stop when parrot isn’t focussing; (detail)

8(c) There are many members of staff at the rescue centre.

The trainer cannot decide whether the parrots will learn
better if the other staff are present or absent while the
parrots are being trained.

8(c)(i) Explain one reason why the parrots may learn better if 2 Explanation for staff presence = 1
the other staff are present during the parrots’ training. Detail = 1

Better if present, if familiar with people; (exp)

They may be less afraid (by people); (detail)

Better if present, people may make them feel secure; (exp)

So they pay attention more / are motivated more; (detail)
Better if present, as people motivate them; (exp)
eg audience effect/social facilitation/showing off; (detail)
social desirability / demand characteristics = 0

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Question Answer Marks Guidance

8(c)(ii) Explain one reason why the parrots may learn better if 2 Explanation for staff absence = 1
the other staff are absent during the parrots’ training. Detail = 1

Better if absent, parrots need to focus to learn; (exp)

Staff might distract them; (detail)

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Question Answer Marks Guidance

9 Faiza is planning to investigate the effect of air pollution

on emotion.

She had planned to conduct a laboratory experiment,

but rejected this for ethical reasons

9(a) Suggest one reason why conducting a laboratory 2 Reason = 1 (can be basic and generic, eg. named
experiment for Faiza’s investigation could have been guideline)
unethical. Linked detail = 1

(risk of) physical harm / (poor) protection of participants;

(reason)
Pollution is dangerous; (linked detail)

(hard to give) informed consent; (reason)

Cannot know in advance of risk damage; (linked detail)

9(b) Faiza decides to use geography students as 2 Linked reason = 1

participants. They are visiting a rural environment and a Detail = 1
polluted city as part of their geography course. She will
collect data in both places.

Explain one reason why Faiza’s new plan is more

ethical.

Students exposed to pollution anyway; (linked reason)

So no more risk of harm than in normal life; (detail)
Rather than deliberately / on purpose / in a lab; (detail)

Consent is only to participate in study; (detail)

So can be fully informed because Faiza’s not causing
exposure; (linked reason)

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Question Answer Marks Guidance

9(c) Faiza is concerned about uncontrolled variables in her 4 uncontrolled variable linked to mood = 1 } x2
study. detail (why hard to control / mood affected) = 1 }

Suggest how two uncontrolled variables could affect the e.g. people might be happier in cities regardless of pollution;
measurement of emotion.

noise in city; (uncontrolled variable)

noise can give you a stress headache; (detail)

city light pollution; (uncontrolled variable)

reduced sleep because of street lighting; (detail)

busy city with lots to do; (uncontrolled variable)

students go to bed late so exhausted; (detail)

time of day (because course may be fixed eg. city in the

morning); (uncontrolled variable)

Question Answer Marks Guidance

10 Bhaavik is interested in the relationship between

shyness and happiness. He says to his friend Jim that
the shy people he knows are really happy, but Jim says
he knows lots of happy people who are not shy.

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Question Answer Marks Guidance

10(a) Describe how Bhaavik could conduct a correlational 10 Use the table opposite to mark candidate responses to this
study to investigate the relationship between shyness question.
and happiness.
To mark Q10(a), create four ‘imaginary columns’ down one
Do not describe sample/sampling technique or ethical margin, using one column for each of the four required
issues/guidelines in your answer. features. Tick each feature (tick-a, tick-b, tick-c, tick-d)
when it appears, then underline the letter( ) for detail.
The four required features for this correlation are:
Use L1, L2, L3, L4, L5 at the end of the response to indicate
(a) two co-variables (shyness defined & happiness the level.
defined).
(b) measure of variable 1 (shyness – how measured) Use the table below to mark candidate responses to this
(c) measure of variable 2 (happiness – how measured) question.
(d) relationship (scatter graph, pos/neg, st/wk)

Note: Both variables must be at least ordinal scales for L3 Level The response:

Level  has all the required features, all with detail,

5 with mostly appropriate terminology.
9–10 AND
marks  clearly applies knowledge of methodology
involved in planning this investigation.
[must be continuous data for both
variables]

Level  has all the required features, but only

4 some of these with detail, with some
7–8 appropriate terminology.
marks AND
 applies knowledge of methodology
involved in planning this investigation.
[must be continuous data for both
variables]

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Question Answer Marks Guidance

10(a)
Level The response:

Level  has some of the required features with

3 detail / all of the required features with no
5–6 detail, and some appropriate terminology.
marks AND
 applies a basic knowledge of methodology
involved in planning this investigation.
[must be continuous data for both
variables]

Level  has at least two of the required features,

2 with little appropriate terminology.
3–4 AND
marks  attempts to use knowledge of methodology
involved in planning this investigation.
[max if clearly an experimental method]

Level  has one of the required features and uses

1 little appropriate terminology.
1–2 AND
marks  makes a limited attempt to use knowledge
of methodology involved in planning this
investigation, e.g. may not use the method
required by the question.

0 No creditable response.
marks

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Question Answer Marks Guidance

10(b)(i) Describe one practical/methodological strength of the 2 identification of generic strength = 1

procedure you have described in your answer to part (a). detail = 1 (generic or linked).
Do not refer to sampling or ethics in your answer.
Strengths of experiments are incorrect
Strengths may relate to: Strengths of ways shyness/happiness was measured in an
Validity experiment are acceptable
 operationalisation
 situational / participant variables
 controls / standardisation
 Demand characteristics
 Reliability
 inter-rater consistency
 intra-rater consistency.

Accept other practical/methodological strengths.

10(b)(ii) Describe one practical/methodological weakness of the 2 identification of generic weakness = 1

procedure you have described in your answer to part (a). detail = 1 (generic or linked).
Do not refer to sampling or ethics in your answer.
Weakness of experiments are incorrect
Weaknesses may relate to: Weakness of ways shyness/happiness was measured in an
 validity experiment are acceptable
 operationalisation
 situational / participant variables
 controls / standardisation
 demand characteristics
 reliability
 inter-rater consistency
 intra-rater consistency.

Accept other practical/methodological weaknesses.

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