## Data and point plots

Introduces the distinction between quantitative and categorical variables through their very different appearances in a point plot.

## Common and Rare

Using distributions to examine which values are common and which are rare.

## Parameters of the normal distribution

Normal distributions are a *family*. The specific members of the family are identified by two parameters: the mean and the standard deviation.

## Shapes of distributions

Introduces terms such as skew, bi-modal, and flat, by reference to the difference of the actual variable from a theoretical normal distribution.

## Comparing two groups

Visualizing sampling variation in the difference between two groups.

## What is a confidence interval?

Describes the desired behavior of a confidence interval, that is, how to know whether a procedure produces a valid confidence interval.

## Comparing two confidence intervals.

Using one-sample confidence intervals on the mean to decide if there's good evidence that two means are different. Statistical experts know to use the two-sample t-test for such problems, but best to build up intuition first and then add mathematical refinements later. And, you'll be able to see for yourself whether the refinements have any practical impact.

## Introducing linear regression

Discussion topics to introduce linear regression to your class.

## Describing relationship patterns in words and numbers

Translating a regression line into a description in everyday terms

## Response and explanatory variables

Reasons to identify one variable as the response and another as the explanatory.

## Intervention and prediction

Causality as a reason to identify one variable as the response and another
as the explanatory.

## How much is explained?

Using R-squared to quantify how much of the variation in a response variable is accounted for by explanatory variables.

## Sampling bias and the confidence interval

A confidence interval will cover the population parameter with the right frequency only if the sample is unbiased. This lesson explores sampling bias. (NOTE: The app used here is in the original style of the Little Apps. It has not yet been translated into the current system used for the Apps.)

## An Example Activity

The generic form of a Little App Activity document. For reference when adding new activities to the site.