2 Flashcards

1
Q

In statistics, some categories are classified as qualitative data. Explain why psychologists consider it to be quantitative.

A

Although the data isn’t numerical, it can be classified into groups and the number of people in each group can be counted up.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are frequency tables?

A

They show the number of observations in each group.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Nominal data is data that exists in categories with…

A

no natural order

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Ordinal data is data that exists in categories with…

A

a natural order

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

4 types of quantitative data

A

nominal, ordinal, ratio, interval

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

ratio data

A

Takes on number values, for which we can tell exactly how much bigger one value is than the other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

interval data

A

Takes on number values, for which we can tell exactly how much bigger one value is than the other

CAN go below 0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

continuous vs discrete data

A
  • discrete data is restricted to certain numbers
  • continuous data isnt restricted to certain numbers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

example of continuous and discrete data

A

continuous (height, temperature, blood pressure)
discrete (number of babies, number of cars, shoe size)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

which data is continuous?

A

ratio, interval

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

which data is discrete?

A

ratio, interval, nominal, ordinal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

5 types of sampling

A
  1. volunteer
  2. opportunity
  3. systematic
  4. random
  5. stratified
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

volunteer sampling

A

Volunteer sampling is when researchers post an advert and wait for people to volunteer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

pro of volunteer sampling
con of volunteer sampling

A
  • easy and reaches lots of people
  • not representative of the population
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

opportunity sampling

A

Opportunity sampling is when a researcher approaches members of the population who are willing and available to be participants.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

pro and con of opportunity sampling

A
  • quick and easy way
  • not representative of the population
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

systematic sampling

A

The third type of sampling is systematic sampling which is when researchers pick every
nth person from the entire
population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

pro and con of systematic sampling

A
  • more representative than volunteer/ opportunity
  • hard as the researcher needs to obtain AND if there is a pattern in how the data is listed, the sample may not be representative of the population
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

random sampling

A

Picking randomly from a list of the entire population, so that everyone has an equal chance of being a participant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

pro and cons of random sampling

A
  • representative as everyone has an equal chance
  • need a list AND a way to randomise AND doesn’t guarantee a representative sample
21
Q

stratified sampling

A

Stratified sampling is when researchers sample so that their sample has the same proportion of each subgroup as the total population.

22
Q

stratified sampling process

A
  1. First, identify important subgroups within your population.
  2. Identify how many people from each subgroup are needed to have the same proportion as the original population
  3. Randomly sample from each subgroup until you get the required number of participants.
23
Q

pro and con of stratified sampling

A
  • most representative
  • may accidentally miss a subgroup AND difficult and time- consuming
24
Q

x and y axis of frequency graph

A

x axis is continuous data
y axis is discrete data

25
Q

histograms

A

Histograms are graphs that represent frequency counts or frequency for continuous data that has been grouped into categories.

26
Q

bar charts

A

Bar charts are graphs that represent
frequency counts for discrete data that has been grouped into categories.

27
Q

Central tendency

A

where the middle of the distribution is

28
Q

Dispersion

A

how spread out the distribution is

29
Q

2 features of distribution

A

central tendency and dispersion

30
Q

mode

A

the most frequently occurring value

31
Q

range

A

measure of dispersion

32
Q

the bigger the standard deviation..

A

the further away the results are from the mean

33
Q

standard deviation

A

Standard deviation measures the distance, on average, of the data from the mean

34
Q

5 steps to calculate standard deviation

A

To calculate the standard deviation:
1. Find the mean of the set of data.
2. Subtract the mean calculated in step 1 from each individual data point.
3. Square the value calculated in step 2.
4. Find the mean of the squared values in step 3.
5. Finally, find the square root of the mean calculated in step 4

35
Q

3 ways to measure central tendency

A

mode, mean, median

36
Q

2 ways to measure dispersion

A

standard deviation, range

37
Q

what do pie charts present?

A

proportions/ percentages

38
Q

in normal distribution:
1SD
2SD
3SD

A

1sd = 68%
2sd = 95%
3sd = 99%

39
Q

Inference

A

taking something we can observe to make a conclusion about something we can’t observe.

40
Q

As the t-value gets bigger, the probability gets…
and the _____ likely the null hypothesis is correct

A

smaller

less

41
Q

3 factors affecting t value

A
  1. difference in mean
  2. dispersion
  3. sample size
42
Q

p value

A

probability of observing our results if the null hypotheses is correct

43
Q

type 1 error

A

researchers incorrectly reject the null hypotheses and say there is a real difference between 2 experimental groups, when really there isn’t

44
Q

significance level

A

The significance level tells us how likely we are to make a type 1 error.

45
Q

type 2 error

A

Researcher fails to reject a null hypothesis which is really false. Here a researcher concludes there is not a significant effect, when actually there really is.

46
Q

significance level to balance risk of type 1 and 2 error

A

To balance the risk of a Type 1 and Type 2 error, we set the significance level to 5 %.

47
Q

degrees of freedom

A

The total sample size across the two groups subtract 2.

48
Q

Primary vs secondary data

A

Primary data- you get yourself
Secondary data - already existing