Ch 1 pt 1 - Intro to Concepts

Question 1

Variables

Answer 1

A characteristic or condition that changes or has different values for different individuals (e.g. age, IQ).

Question 2

Constant

Answer 2

Something that doesn’t change or remains constant.

Question 3

Quasi experimental research

Answer 3

When researchers use already-existing groups. This is not a true experiment.

Question 4

Independent variable

Answer 4

Variable manipulated or controlled by the experimenter.

Question 5

Dependent variable

Answer 5

Variable observed for changes.

Question 6

Qualitative variable- Categorical

Answer 6

Variables with no natural sense of ordering. It can be coded to appear numeric, but the numbers are meaningless (e.g. hair colour: black=1, brown=2, red=3)

Question 7

Quantitative variable

Answer 7

Variables that are measured on a numeric or quantitative scale. Numbers have some meaning to them (e.g. shoe size: the higher the shoe size, the bigger the shoe).

Question 8

Discrete variables

Answer 8

Values fall only at particular points on the scale of measurement. Indivisible categories (e.g. number of children: one can’t have 2.5 kids). In the case of discrete variables, it doesn’t make sense to compute a mathematical average.

Question 9

Continuous variables

Answer 9

Values can fall at any point on an unbroken scale of measurement. Any value represents all points between the real limits. Divisible categories (e.g. distance: you can be 2.5 km away).

Question 10

Scales

Answer 10

Used to record scores on qualitative or quantitative variables.

Question 11

Nominal scale (qualitative data)

Answer 11

Scale defined by name alone (e.g. hair colour, type of cat)

Question 12

Ordinal scale

Answer 12

Separate categories presented in rank order (e.g. 1st place, 2nd place, 3rd place). The numbers assigned indicate the relative amount of a variable arranged in rank order of magnitude (e.g. rating satisfaction: very satisfied is better than very dissatisfied, but we can’t quantify by how much)

Question 13

Interval scales

Answer 13

Same as ordinal scale. Numbers indicate both the order of magnitude and equal intervals between the measures (e.g. a difference of 5°C between 10°C-15°C means the same as the 5°C between 30°C-35°C). There is an arbitrary 0, so ratios are not equal (e.g. In the Celsius scale, 0°C is arbitrary. So even though intervals are equal, they don’t represent equal ratios. 20°C is not twice as hot as 10°C).

Question 14

Ratio scales

Answer 14

Same as interval scales, but it has an absolute 0 (e.g age: someone who is 6 is half the age of someone who is 12).

Question 15

Data

Answer 15

The information we collect in a research study.

Question 16

True score

Answer 16

The observed score, plus an error.

Question 17

Error

Answer 17

The observed score may fluctuate for a variety of reasons. These fluctuations are called errors.

Question 18

Population

Answer 18

All individuals of interest in a particular study as defined by the researcher. Population can be large or small depending on how the researcher defines the it.

Question 19

Sample

Answer 19

All individuals selected from a population, usually intended to be representative of that population (a sub-set of the population).

Question 20

Random selection

Answer 20

each person has an equal chance of being selected as part of the sample.

Question 21

Stratified sampling

Answer 21

Researchers deliberately select samples for characteristics that mimic the population.