Section 3 Flashcards
What is quanrirative data?
Numerical values e.g reaction time or number of mistakes
Advantage and disadvantage of quantative data
- Easier to analuse: Cna draw graphs and average , can ‘eyeball’ data and patterns at glance
- Oversimplifies behaviour : e.g use scale for feelings , individual meaning lost
What is qualitative data?
Non-numerical data expressed in words
e.g extract from diary
Advantage and disadvantage of qualatative data:
- Represents complexities: More detail plus feelings , can also include info unexpected
- Less easy to analyse: Large amount of detail difficult to summarise and draw conclusions from
What is primary data?
‘First hand’ data collected for the purpose of investigation
Advantage and disadvantage of primary data:
- Fits the job: study desgined to extract only data needed as information is directly relevant to aims
- Requires time and effort: Design may involve pllaning and preparation as secondary data acessed within minutes
What is secondary data?
Collected by someone other than person who is conducting the researche.g taken from journal articles , books , websites
Advantage and disadvantage with secondary data
- Inexpensive: Desired information may already exist , requires minial effort and inexpensive
- Quality might be poor: Info incomplete or outdate so challenges validity of findings
What is meta-analysis?
Type of secondary data that involves combing data from large number of studies
Calculation of effect size
What is a table used for?
Raw scores are displayed on columns and rows
What is a bar chart?
Caterrgories (discrete data) usually placed on x and freq on y
Height of column represent frequency of that item
What is a histogram?
Bars that touch each other data is continous rather than discrete
What is a scattergrah?
Used for correlational analysis
Each dot represent one pair of related data
data must be continous
MUST BE CORRELATION/RELATIONSHIP IN TITLE
NO LINE OF BEST FIT
What are the two measures of dispersion?
/Range
Standard deviation
What happens the bigger the range?
Bigger range of results
What is the standard deviation?
Measure of average of spread around the mean
Larger SD , more spread out data
What are the three central tendency?
Mean
Median
Mode
What is mean?
Airthemtic average
Add up all score
deivide by number of scores
Advantages of mean and disadvantages
- Sensitive: Includes all scores in data set within calculation , overall impression of average than mode and median
- Unrepresentative: Only one very large or small number makes it disorted , median and mode not disorted
What is median?
The middle value , places scores in ascening order and select middle value
If two values in middle , mean is calculated
Advantage and disadvantage of median
Advantage: Unaffected by extreme scores as only focused on middle value so more representative as a whole
Less senstive than mean: Not all scores included so extreme values may be important
What is mode?
Most frequent/common value used with categorial/nominal data
Advantage and disadvantage of mdoe
- Relevant to caterogical data: When it is discrete , mode is only approperiate
- Overly simple measure: Many modes in data set , not useful when describing many sets to use mode
What is range?
Difference between highest to lowest value
Advantages and disadvantages of ranges:
- Easy to calculate as arrange values , simple formula than SD
- Does not account for disturbition fo scores , does not indicate whether most numbers are closely grouped or spread out evenly - SD is better dispersion
Advantages and disadvantages of standard devistion
More precise: includes all values in calculation , more accurate picture of data set
Misleading; ‘Hide’ some characteristic of data as extreme values not releaved unlike range
What is correlation analysis?
Measure strength and direction of relationsgio between two variables
What is co-variable?
Variables that have been used up when looking at correlations
What is positive correlation?
As one variables rises , other variables increases
What is negative correlation?
As on variable increases other variable decreases
What is zero correlation?
No relationship between variables
What is difference between correlation and experiment?
Ex : Establish cause and effect
Correlation; Relationship between variables
How to analyse correlational analysis values?
+/- -positive or negative correlation
close to 1 - strong
closer to 0 - weaker
if -1 to -0.7 - statistically significant
0.7 to 1 - statistically significant
Advantage and disadvantage of correlation
- Useful point for research as assess strength and direction of relationship so provide precise measurements - if strongly suggested it would suggest hypothesis
- No cause and effect are casual as they may be other intervening variables explaining relationship
What is normal disturbtion?
Symmetrical spread of freq data forming bell-shape pattern
Mean
median
mode
located at highest peak
What is skewed disturbution?
A spreaf of frequency data that is not symmetrical
data clusters to one end
What is positive skew?
Type of disturbition in which long on positive right side of peak and most of disturbition is concentrated on lleft
What is negative skew?
Type of disturbition in which long is on negative (left) side and peak and most disturbition concentrated on right
Features of normal disturbition
- Mean , median and mode is exact midpoint
- Disturbition is symmetrical around midpoint
- Disperison of scores of midpoint express in SD
Graph of normal , positive , negative disturbition
Instructions of sign test:
- Conver the following into + , - , =
- Total number of + , -
- Total value of S: (lowest value of + and -)
- Value of N (total number of scores ignoring =)
- Compare N value with critical value
- Calculated S = or less than critical value to be significant
What determine + - =
Minus column
if negative number -
If positive +
If equal =
What is sign test look for?
- Look for difference of scores (not correlation)
- Used repeated measure experimental design
- Data organised in categories (nominal data)
What does 0.05 accepted probability
5% likely that difference due to chance
What should my critical value be?
EQUAL or LESS than table deemed signification (IV cause change in DV)
What is Peer Review?
When a psychological work is assessed by specialist in the same field to ensure any research intended fro publication is of high quality
What does peer review involve?
The written aprt of an investigation scuntiised by small group.
These experts unknown to researcher should be objective and not influenced by their personal viewpoints/opnions
