Welcome to the course!

Foundations of Inference in R

Jo Hardin

Instructor

What is statistical inference?

 

 

The process of making claims about a population based on information from a sample

Foundations of Inference in R

What is statistical inference?

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Foundations of Inference in R

What is statistical inference?

What is statistical inference - 2.png

Foundations of Inference in R

What is statistical inference?

What is statistical inference - 3.png

Foundations of Inference in R

What is statistical inference?

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Foundations of Inference in R

Assume two populations prefer cola at same rate

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Foundations of Inference in R

The sample data

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Foundations of Inference in R

The sample data (take 2)

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Foundations of Inference in R

Vocabulary

 

Null hypothesis ($H_0$): The claim is not that interesting

Alternative hypothesis ($H_A$): The claim corresponding to the research hypothesis

 

The "goal" is to disprove the null hypothesis

Foundations of Inference in R

Example: cheetah speed

 

Compare speed of two different subspecies of cheetah

$H_0$: Asian and African cheetahs run the same speed, on average

$H_A$: African cheetahs are faster than Asian cheetahs, on average

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Foundations of Inference in R

Example: election

 

From a sample, the researchers would like to claim that Candidate X will win

$H_0$: Candidate X will get half the votes

$H_A$: Candidate X will get more than half the votes

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Foundations of Inference in R

Let's practice!

Foundations of Inference in R

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