IBMATHAI: U2 Modelling Statistics VOCAB

Univariate Data

One Variable

Qualitative Data

Categorical

Quantitative Data

Numerical

Discrete

Counted data; Specific values

Continuous

Measurable data

A population

Whole group

Sample

A small group chosen from the population

Simple Random Sampling

Selecting a sample completely at random

Systematic Sampling

Selecting a sample at a regular interval

Convenience Sampling

Getting data by selecting an easy to reach population

A biased sample

sample that does not represent diversity of population

Quota sampling

setting certain quotas for your sample

Stratified Sampling

selecting random sample where numbers in certain categories are proportional to numbers in their population

Percentile

Score below which a certain percentage of data lies

Lower quartile; 25th percentile

(n+1)/4

Median

(n+1)/2

Upper quartile; 75th percentile

(3(n+1))/4