Lecture 10

Question 1

The idea that the independent variable varies between groups of people

Answer 1

It’s very versatile and has lots of advantages, such as, each participant only subjects to one treatment condition. The disadvantage is that you need a lot of people, therefore the groups would differ.

Question 2

Within-Subjects Design
adatgae and disadavtage

Answer 2

Advantages include, fewer participants are needed than in a corresponding in between subjects design
Disadvantages include progressive error because performance is also influenced by experience of repeatedly participating

Question 3

Validity Considerations

Answer 3

Internal Validity
External Validity:

Question 4

Internal Validity

Answer 4

Quality of experimental control: something we can well influence, how well i can do my experiment

Question 5

External Validity

Answer 5

Generalizability of findings: to what degree the results that are obtained are valued outside my experimental context.

Question 6

Empirical Structuralism

Answer 6

argues instated validity is not a useful criterion for theory evolution. This is because theories are tied to their intended applications, and you cannot generalize beyond that scope.

Question 7

Each theory consist of

Answer 7

The core: central assumptions
The intended applications: the empirical situations that the theory is meant to describe
The paradigmatic method: defines how the core is applied

Question 8

Types of Distributions

Answer 8

Negatively Skewed
Positively Skewed
Normal Distribution

Question 9

distribution

Answer 9

Distribution is the spread of the data points across the range of possible measurements,

Question 10

Measures of Central Tendency

Answer 10

mode
median
mean

Question 11

mode

Answer 11

Most frequent value – the value that most occurs in a dataset, in a frequency distribution this is the category with the highest frequency

Question 12

Median

Answer 12

Middle value – the data point for which half of all data points are higher in value and half are lower in value

Question 13

Mean

Answer 13

Average value – competed by adding a;l; values and diving the number of the data points that were added up

Question 14

Standard Deviation

Answer 14

Average distance from mean – a measure of the amount of variability in a data set. A large standard deviation means the data in the distribution are spread wide around the mean, a small one that they are closely scattered around the mean

Question 15

What is a Type I error?

Answer 15

Rejecting the null hypothesis when it is actually true (false positive).

Question 16

Example of Type I error?

Answer 16

Concluding a drug works when it actually doesn’t.

Question 17

What is a Type II error?

Answer 17

Failing to reject the null hypothesis when it is actually false (false negative).

Question 18

Example of Type II error?

Answer 18

Concluding a drug doesn’t work when it actually does.

Question 19

Which error is like a “false alarm”?

Answer 19

type 1

Question 20

Which error is like “missing a real effect”?

Answer 20

type 2

Question 21

Frequency

Answer 21

The number of observations that fall within a certain category or range of scores.

Question 22

Statistical Primer:

Answer 22

Psychologists use descriptive statistics, a set of techniques used to summarise and interpret data. This gives you the big picture of results. Statistics is used to understand 3 data types, frequency, central tendency and variability.

Question 23

Normal distribution

Answer 23

a symmetrical distribution with values clustered around a central mean value

Question 24

Negatively skewed distribution

Answer 24

A distribution in which the curve has ab extended tail to the left of the data

Question 25

Positively skewed distribution

Answer 25

A distribution in which the long tail is on the right — Most of the time skews occur because there is an upper or lower limit to data.

Question 26

Central Tendency

Answer 26

When examining data it is often useful to look ar where scores seem to cluster together. When we do this we are estimating central tendency. \\

Question 27

So, if the three measures of central data are equal, which do we use?

Answer 27

If the data are normally distributed, researchers generally use the mean The measure used least is the mode, because it provides less information than the mean or the median The mode is typically only used when dealing with categories of data.

Question 28

What is variability in psychology/statistics?

Answer 28

The measure of how spread out or different data points are from each other.

Question 29

Why is variability important?

Answer 29

: It shows how consistent or inconsistent data is and helps us understand how reliable averages (like the mean) are.

Question 30

What are the main measures of variability?

Answer 30

: Range, variance, and standard deviation.

Question 31

What is the range?

Answer 31

The difference between the highest and lowest values in a dataset.

Question 32

: What is variance?

Answer 32

The average of squared differences from the mean.

Question 33

Hypothesis Test

Answer 33

A statistical method of evaluating whether differences among groups are meaningful, or could have been arrived at by chance alone.

Question 34

Statistical significance

Answer 34

a concept that implies that the means of the groups are father apart than you would expect them to be by random chance alone.

Question 35

The Null Hypothesis

Answer 35

which assumes that any differences between groups are due to chance

Question 36

The experimental hypothesis

Answer 36

which assumes that any differences are due to a variable controlled by the experimenter.

Question 37

Experiment:

Answer 37

: Manipulation of an independent variable under carefully controlled conditions to see whether any changes occur in a dependent variable — Example: Schachter’s (1959) study of whether increased anxiety leads to increased affiliation

Question 38

Naturalistic Observation:

Answer 38

Prolonged observation of behaviour in its natural setting, without direct intervention

Question 39

Case Studies:

Answer 39

An in depth investigation of single individual using direct interview, direct observation, review of records, interviews of those close to the person, and other data sources

Question 40

Surveys:

Answer 40

Use of questionaries or interviews to gather information about specific aspects participants behavior, attitudes, and beliefs

Question 41

Frequency Distribution:

Answer 41

An orderly arrangement of scores indicating the frequency of each score or a group of scores

Question 42

Frequency polygon:

Answer 42

Is a line figure used to present data from a frequency distribution.

Question 43

Percentile score:

Answer 43

a percentile indicates the percentage of people who score at or below a particular score

Question 44

A correlation exists when

Answer 44

two variables are related to each other.

Question 45

The correlation coefficient is a

Answer 45

numerical index of the degree of relationship between two variables. A correlation coefficient indicates the direction of the relationship and how strongly the two variables are related.

Question 46

Inferential Statistics

Answer 46

are used to interpret data and draw conclusions. Working with the laws of probability researchers use inferential stats to evaluate the possibility that their results might be due to the fluctuations of chance.

Question 47

A meta analysis

Answer 47

A meta-analysis is a study that combines results from many studies to find an overall conclusion.

Question 48

A sample

Answer 48

is the collection of subjects selected for observation in an empirical study. In contrast, the population is the much larger collection of animals or people (from which the sample is drawn) that researchers want to generalise.

Question 49

The strategy of observing

Answer 49

a limited sample in order to generalise about a much larger population rests on the assumption of the population.

Question 50

Sampling bias exists

Answer 50

when a sample is not representative of the population from which it was drawn. When a sample is not representative, generalizations about the population may be inaccurate.

Question 51

Reliability

Answer 51

Another important aspect of data is reality, the stability and consistency of a measure over time. If the measurement is reliable, the data collected will not vary substantially over time.

Question 52

accuracy

Answer 52

the degree to which the measure of error is free. A measure may be reliable but still not accurate