Statistics: Analyzing Quantitative Data

Review of Histograms

Do Now:

1. Describe the histogram using SOCS

2. How many extra curricular activities do you participate in?

1. Designate one person from your table group to come to the board and document each group member’s answer.

Overview

• Grades/Quiz• Homework tonight: Journal• Overview of this week

Homework from Friday

• Questions on just the part involving histograms?

Histograms:

• What is the biggest difference between a histogram and a bar graph?

Histograms:

• The bars are always touching• Used to describe Quantitative Data– Whereas Bar graphs are used to describe

Categorical Data

• When creating a histogram: – I will never penalize you for what you choose as a

“bin width” (within reason)– You need to have a title and label your axis.

Histogram of Extra Curricular Activities• Let’s create it!

• First– what’s the context for this data?– Who?– What?– When?– Where?– Why?– How?

• What kind of variables do we have?

Create a histogram Example B:

• The Cornell Lab or Ornithology holds an annual Christmas Bird Count, in which birdwatchers at various locations around the country see how many different species of birds they can spot. Here are some of the counts reported from sites in Texas during the 1999 event.

178 186 162 206 166 163 183 181 206 177175 167 162 160 160 157 156 153 153 152

228

a. Create a histogram of the datab. Write a brief description of the data

Describing Histograms:

• SOCS: – Shape: Modal + Symmetric vs. Skewed– Outliers?– Center – Spread

Example One:

Follow Up:

• Would you expect the mean to be larger or smaller than the median? – Why?

Example Two:Temperature in the Bahamas over the course of a year

Temperature

Freq

uenc

y

Follow Up Question

• In the last example, would you expect the mean to be larger or smaller than the median?– Why?

Example Three:

• What’s wrong with this histogram?

Practice Problems

• Try some in your table groups!

Exit TicketUse SOCS to describe the histogram below