Week 10-14 Flashcards
Give an example: Nominal level of measurement
Ethnic group- Chinese
Give an example: Ordinal level of measurement
University grades- pass, credit
Give an example: Interval/Discrete level of measurement
IQ scores
Give an example: Ratio/Continuous level of measurement
Height
Give an example: Categorical Data
Nominal and Ordinal
Give an example: Continuous data
Interval and Ratio
Define: Continuous data
is an actual value of the measurement
Define: Categorical data
is the number of cases that fall into a category
What are the 3 measures of Central Tendency?
Mean
Median
Mode
Define: Median
is the score that divides a ordered set of scores into two equal halve
Define: Mean
the average
Sum of a set of scores, divided by the number of scores
What are the measures of Variability?
Range
Percentiles and Quartiles
Standard Deviation
Measures of Variability
Define: Variability
Dispersion or spread of scores
Define: Range
Difference between the highest and lowest score
highest score - lowest score = range
Measures of Variability
Define: Percentiles and Quartiles
Percentiles divide data into 100 equal portions
Quartiles divide data into 4 quarters
• Q1=25%,Q2=50%,Q3=75%, Q4=100%
Measures of variability
Define: Standard Deviation
It is the average difference between any score and the mean
- Important because it includes information on all scores
What is called the Point Estimate?
the mean or median
What is called the Measure of Variability?
the Standard Deviation or the Inter-quartile range
What is the purpose of Descriptive Results?
Concerned with organising and summarising information about a collection of actual observations
Descriptive Results
Name the 3 ways data is described?
1) By measures of central tendency2) By measures of dispersion (variabiltiy)
3) By measures of association
Descriptive Results
Name the methods of describing data
with:
1) Numbers- percentages, SD, central tendency
2) Tables/Figures- Bar chart, histogram, polygon, scattergram
Name the 2 Frequency Measures in epidemiology
Incidence
Prevalence