1-Variables, scores and values

Question 1

What are variables?

Answer 1

Physical or abstract attributes or quantities that we wish to measure

Question 2

What is a score ?

Answer 2

The value that an individual has on a particular variable.

Gurnsey, Rick. Statistics for Research in Psychology (p. 5). SAGE Publications. Édition du Kindle.

Question 3

What are quantitative variables?

Answer 3

Variables whose values are numbers

Question 4

What are Qualitative variables ?

Answer 4

Variables whose values are qualities

Question 5

What constitutes a Ratio Scale?

Answer 5

1) Absolute zero, because with compare the distance of the two values with the absolute zero
2) A unit of measurement

Question 6

What are discrete quantitative variables?

Answer 6

They have fixed values, so intergers or whole numbers

Question 7

What are quantitative continuous variables?

Answer 7

IThey have values that are real numbers

Question 8

What constitutes an Interval Scale ?

Answer 8

1) Unit of measurement

2) NO abosulte zero

Question 9

What types of variable are measured on a nominal scale ?

Answer 9

1) Qualitative
2) Discrete
3) Unordered categories

Question 10

What are Ordinal Variables?

Answer 10

A variable with properties of both quantitative and qualitative

Question 11

What constitutes an ordinal scale ? Give an example

Answer 11

1) Measure qualitative and discrete variables
2) Natural ordering, but No unit of measurement

ex: Letter Grade (A+, A, A-, etc.)

Question 12

Give the Stevens Hierarchy of Scales

Answer 12

1. Ratio scales
2. Equal interval squale
3. Ordinal scales
4. Nominal scale

Question 13

What is a psychocologial construct ?

Answer 13

An hypothetical attribute that explains some types of behavior

Question 14

What is an operational measure?

Answer 14

A tool used to measure psychological construct

Question 15

What is validity?

Answer 15

When we measure what is supposed to be measured

Question 16

What is reliability?

Answer 16

When the device give similiar or identical measurements every time it is applied to the same object

Question 17

What is measurement error?

Answer 17

Everytime something is measured, there is going to be a slighty different score

Question 18

What is a population?

Answer 18

Collection of individuals that share a common caracteristic of interest

Question 19

What is a sample?

Answer 19

A subset of the population

Question 20

What is a parameter?

Answer 20

A numerical characteristic of a population

Question 21

What is a statistic?

Answer 21

A numerical characteristic of a sample

Question 22

What are inferential statistics?

Answer 22

The act of infering a population paramaters from a sample statistics

Question 23

What are descriptive statistics?

Answer 23

To describe a collection of scores, without inferring anything about a population parameters

Question 24

What is simple random sampling ?

Answer 24

All members of a population have an equal chance of being selected in a sample

Question 25

What is sampling bias?

Answer 25

It means that not all members of a population have an equal chances of being in the sample

Question 26

What are convenience samples?

Answer 26

A sample that is conveniently available

Question 27

What is a sampling error?

Answer 27

The difference between a statistic and the parameter it estimates. It can NOT be avoided.

Question 28

What is a sampling distribution?

Answer 28

A probability distribution of all possible values of a sample statistic based on samples of the same size.