BS161: Lecture 1 - Intro to Statistics

What is Epistemology?

Branch that tells us where knowledge comes from

What is Empiricism?

Knowledge based on experience

Science is Empirical, what does this mean?

Materials and tools needed

What is the Population in a Stats Test?

Everything we want to measure

What is the Sample in a Stats Test?

What we can measure

What are Discrete Variables?

No intermediate values, fixed

What are Continuous Variables?

Infinite values between 2 values

What are Categorical Variables?

Groups/categories

How are Ranked Variables different to Categorical Variables?

Ranked if groups can be sorted

What is the purpose of the Descriptive Statistics of Centrality?

Unique numbers that summarise sample trends

What are the Descriptive Statistics of Centrality?

Mean, Median, Mode

Can Dispersion Patterns be different?

Datasets w/ same mean & sample size can have different dispersion patterns

What is the purpose of the Descriptive Stats of Dispersion?

Unique numbers that summarize sample variability

What are the Descriptive Statistics of Dispersion?

Range, Variance, Standard Deviation

What is Variance?

Average of squared differences

When are Histograms used?

1 numeric variable

What are Histograms used for?

Exploring data distribution

When are Scatter Plots used?

2 numeric variables

What are Scatter Plots used for?

Relationship between 2 values

When are Bar Plots used?

1 numeric variable

What are Bar Plots used for?

Differences between data

When are Box Plots used?

1 numerical, and 1 categorical variable

What are Box Plots used for?

Differences between categories

What does the IQR Measure?

Spread of the central 50% of the data

Which graph type is most appropriate for categorical data?

Bar chart

Parameter

numerical summary describing a population

Statistic

numerical summary of a sample

Standard Error

SD of sampling distribution

Effect of increasing sample size on standard error

Decreases