Research Methods and Design Questions and Answers

Answer: C

The keyed answer is 24 hour diet recall.

A 24-hour recall asks a person to list everything eaten and drunk in the previous day, with amounts, and the amounts are then converted into energy and nutrient intakes. Indian diet-survey practice names it with weighment as a standard way to measure what is eaten, and nutrition research treats it as a quantitative dietary method, checked against weighed records.

Focus group discussion and the case study are qualitative methods: they gather views, experiences and detailed description, not counts or measures. Structured observation is the closest rival, because observation with a fixed schedule can be counted and is sometimes called quantitative in research-methods books. The key prefers the diet recall because it measures amounts of intake directly, and in a Home Science paper that is the method meant, so I follow the key while noting that structured observation is a defensible second.

Answer: D

This is referred to as a sampling frame.

A sampling frame is the list of all units in the population from which a sample is actually drawn. When children are selected from a school, the attendance register serves as that list.

Sampling is the general process of selecting a sample, random sampling is a method in which each unit has an equal chance of selection, and the lottery method is one way of drawing a random sample. All three describe how a sample is drawn, not the list it is drawn from.

Answer: A

The key's answer is Experimental method.

A nominal variable sorts people into categories, such as treatment and control groups, while an interval variable gives measured scores. That is the typical structure of an experiment: the groups (nominal) are the independent variable and the measured outcome (interval) is the dependent variable, compared with tests such as t or ANOVA.

The correlation method needs two variables measured on at least an ordinal or interval scale, a case study examines one unit in depth without measuring such variables across groups, and the cross-sectional method describes when data are collected rather than how the two variables relate.

Answer: A

Two variables are correlated when a change in one variable results in a corresponding change in the other.

Correlation means the two vary together in a systematic way. The relation is positive when they move in the same direction (height and weight) and negative when they move in opposite directions (price and demand).

'Change in opposite directions' describes only negative correlation, not correlation in general. Whether variables are similar or dissimilar in nature has nothing to do with whether they are correlated.

Answer: B

The advantage of closed-ended questions is that they reduce coding errors.

Because respondents choose from fixed answers, the responses are already in categories that can be pre-coded, so coding, tabulation and analysis are quick and consistent, with little room for coder judgement or error.

The other three are disadvantages of closed questions. Ruling out marginal or unexpected answers loses information, and the fixed choices may not cover the full range of possible responses. Taking more time for analysis is a drawback of open-ended questions, not of closed ones.

Answer: C

The key gives a case study of individual child as Piaget's clinical method.

Piaget's clinical method was a flexible, individual interview: he presented one child at a time with a task or question and followed up each answer with further questions to uncover the reasoning behind it. Because it studies each child's thinking in depth, the option describing an individual case study is the closest of those given.

A standardized questionnaire asks every child the same fixed questions, the opposite of Piaget's flexible probing, and an open-ended questionnaire is still a written instrument without follow-up questions. The method was called clinical after psychiatric interviewing, but it was not carried out on children in a psychiatric clinic.

Answer: C

The control group is a term used in experimental research.

In an experiment the subjects are divided into an experimental group, which receives the treatment, and a control group, which does not. Comparing the two shows the effect of the treatment, because other conditions are kept the same for both.

Survey and descriptive research describe existing conditions without manipulating any variable, and historical research studies past events from records. None of them assigns a treatment, so none needs a control group.

Answer: A

A correlation coefficient of zero indicates a non-existent relationship (no linear relationship).

The coefficient r ranges from -1 to +1. Values near +1 or -1 show a strong positive or negative linear relationship, and r = 0 shows that the two variables have no linear association at all.

'Existent' and 'direct' relationships require a non-zero coefficient, a direct relationship being a positive one. 'Neutral' is not a term used to interpret correlation coefficients. Strictly, zero rules out only a linear relationship, but at this level it is read as no relationship.

Answer: D

The type of hypothesis among the options is the null hypothesis.

The null hypothesis (H0) states that there is no difference or no relationship between the variables studied. Statistical tests are designed to reject or fail to reject it, and the alternative hypothesis (H1) states the difference or relationship the researcher expects.

'Zero hypothesis' is a literal rendering of 'null' but is not the term used. Absolute and abstract hypotheses are not recognised types; the usual classifications are null and alternative, directional and non-directional, and descriptive, relational and causal.

Answer: C

The key's answer is that experimental researches are aimed to study the application of theory.

An experiment starts from a theory, derives a prediction from it (a hypothesis about cause and effect), and then deliberately manipulates the independent variable under controlled conditions to see whether the predicted effect appears. In this sense an experiment puts a theory into practice and tests whether it holds.

Merely establishing an association between variables is the aim of correlational research, which observes variables without manipulating them. Describing variables is the aim of descriptive or survey research, and trend analysis belongs to historical and longitudinal studies.