Lecture 1: Variables And Variability

Question 1

Variables

Answer 1

Something that can be measured and something that can vary across different dimensions

Question 2

Why do we need Statistics?

Answer 2

1. To describe variations
2. To explain variation and evaluate relationships between variables

Question 3

Scales of measurements for variables (5 main ones)

Answer 3

1. Binary
2. Nominal
3. Ordinal
4. Interval
5. Ratio

Question 4

Binary Scale

Answer 4

Only two possible values eg. Heads/tails, Yes/No

Question 5

Nominal scale

Answer 5

consists of purely qualitative categories with no quantitative meaning order eg. Nationality, Fav item, Blood type

Question 6

Ordinal Scale

Answer 6

Inherently ordered categories indicating the rank or amount of something eg. Likert scales, highest level of education completed

Question 7

Interval scale

Answer 7

Consists of meaningful differences/intervals between values on the scale. Differences on scale consistently reflect differences in the quantity being measured eg. Temperature

Question 8

Ratio Scale

Answer 8

A type of interval scale of which zero indicates a true absence of the quantity. Meaningful Ratios eg. Items you can count, Heart Rate, Age, Height

Question 9

Continuous Variables

Answer 9

Has values that can be at any of the infinite points along a continuum. Infinite number of values eg. Height, weight, heart rate

Question 10

Discrete variable

Answer 10

No infinite values between 2 points eg. Students (No 1/3 of student possible), No. of sex partners