3.2.3.2 Data handling and analysis Flashcards
What is quantitative data?
Information that can be measured and written down with numbers
Name cons of quantitative data
- Lacks details
Name pros of quantitative data
- Quick and easy to analyse
- Easy to compare
- Immediately quantifiable
- Measured objectively
What is qualitative data?
Descriptive information that is expressed in words
Name cons of qualitative data
- Time consuming/difficult to analyse (lots of detail)
- Hard to make comparisons
- Based on subjective interpretation of language
- Not immediately quantifiable, data has to be transformed and only quantifiable if data is put into categories and frequency is counted
Name pros of qualitative data
- Lots of detail given
- Allows more depth of analysis
What is primary data?
Information that a researcher has collected him/herself for a specific purpose
e.g. data from an experiment or observation
Name pros of primary data
- More relevant to topic of research = degree of accuracy is high
- Greater validity ∵ study is designed and carried out for main purpose of research (collected objectively)
Name cons of primary data
- Expensive to obtain
- Limited to time, place and no. of participants
- Secondary data can come from different sources & give more range and detail
What is secondary data?
Information that someone else has collected
e.g. the work of other psychologists or government statistics
Name pros of secondary data
- Easy and quick to collect
- Large variety of it
Name cons of secondary data
- Data may be unreliable
- May be out of date
What is meta-analysis?
- A technique where researchers examine results of several studies
- Rather than conducting new research with participants
Name pro of meta-analysis
Reduce problem of sample size
Name con of meta-analysis
Lots of conflicting results
What do descriptive statistics help to do?
Help simplify large amounts of data
Name 2 types of descriptive statistics
- Measures of Central Tendency
- Measures of Dispersion
Name pro of mean
- Most sensitive ∵ includes all values in data set within calculation
- More representative of data as whole
Name con of mean
- Easily distorted by extreme values
- = mean doesn’t represent the average of data set as a whole
Name pro of median
- Not affected by extreme scores
- More representative of overall data set
Name con of median
- Less sensitive then mean
- Not as representative as mean
Name pro of mode
For data that appears in categories = only method you can use
e.g. favourite desserts
Name con of mode
Basic - Doesn’t repent data set as a whole
Name pro of range
Easy to calculate
Name con of range
- Only takes account 2 most extreme values
- Unrepresentative of data set as whole
What does standard deviation tell us?
Tells us how far scores deviate from mean
What does a large SD tell us?
- Lots of spread within data set
- e.g. not all participants were affected by IV in same way
- May be few anomalous/extreme values
What does a small SD tell us?
- Data tightly clustered around mean
- Suggests participants respond in fair similar way to IV
Name a pro of standard deviation
Very precise (more than range), includes all values in data set
Name a con of standard deviation
SD can be distorted by extreme values
Why do we use graphs and tables?
Allows us to ‘eyeball’ data and see findings at a glance
Name 4 presentations/displays of quantitative data
- Bar Chart
- Histogram
- Line Graph
- Scatter Graph
Draw a normal distribution. Label the mode, median, mean on it.

Draw a negatively skewed distribution. Label the mode, median, mean on it.

Draw a postively skewed distribution. Label the mode, median, mean on it.

Describe the long tail in a postive skew
Long tail is on positive side of peak
Describe the long tail in a negative skew
Long tail is negative side of peak
What does statistical testing tell us?
Tell us whether difference/relationship between variables are statistically significant or if they’re occurred by chance
What are inference tests?
Statistical tests that allow us to infer things about what data means
State the difference between descriptive and inferential statistics
- Descriptive statistics
- Describe summary of data
- Inferential statistics
- Allows us to make conclusion
- Make an inference about data
Statistical Testing
State significance/probability
- Accepted level of probability = 5%
- p < 0.05
- Result occurred by chance is equal or less than 5%
Name 3 factors to determine which inferential test should be used
- Research design
- Research aim
- Type of data (level of measurement)
Factors to determine which inferential test should be used…
Describe research design
Data can be related or unrelated
- Related data is produced from repeated measures and matched pair designs
- Unrelated data is produced from independent group designs
Factors to determine which inferential test should be used…
Describe research aim
Looking for a difference/relationship?
Name 3 types of data
- Nominal
- Ordinal
- Interval/ratio data
Describe nominal data
Distinct category
Describe ordinal data
List of data that can be ranked in order
e. g. subjective rating of happiness from a questionnaire
(i. e. happiness rating of 10 is higher than 5, but 2x as happy as 5)
Describe interval/ratio data
- Measured on a scale in which each interval is exactly same size
- e.g. time, 10s 2x as long as 5s
- Continuous
Describe when you used use the Sign Test (i.e. the 3 conditions)
- Looks for a difference
- Used for repeated measures designs
- Data is nominal
The Sign Test
Describe Step 1
- Participant value in ‘experiment’ column − participant value in ‘control’ column
- Record its sign (+,-,0)
The Sign Test
Describe Step 2
- Count no. of times the LESS FREQUENT sign occurs
- This gives us S
The Sign Test
Describe Step 3
- Count total number of pluses and minuses
- This gives us N
The Sign Test
Describe Step 4
Decide if hypothesis was directional or non-directional
(directional = one-tailed, non-directional = two-tailed)
The Sign Test
Describe Step 5
Reading Critical Tables
- Use critical table to find N and 0.05
- & then determine if results are significant
The Sign Test
Describe Step 6
State the conclusion
- If result significant = accept experimental hypothesis
- If result insignificant = accept null hypothesis
Hypothesis: the recall of word lists will be greater in the silent condition compared to the noise condition
State whether the results are significant & the conclusion. Show all your working.

Results are significant. so we accept the experimental hypothesis