# Sampling to draw inferences about a population

Measures of central tendency and range

• Glencoe 11-4
• Mean, median, mode, and range
• Concept summary notes
• Examples 1-2 with CYP’s
• Assignment: P. 588-589 (5-15 All, 18)

Measures of variation

• Glencoe 11-5
• Upper and lower quartiles
• Example: Find the median, lower quartile, upper quartile and interquartile range of the following data set of scores: 18     20     23     20     23     27     24     23     29
• Outliers
• Assignment: P. 596-597 (6-9, 14-17, 28-33)

Box-and-whisker plots

• Glencoe 11-6
• Khan academy: constructing a box-and-whisker plot (descriptive statistics)
• Assignment: P. 603-604 (7, 9, 10-23 All)

Histograms

What is a Histogram?

A histogram is a bar graph that shows the frequency of data intervals. In other words, it is a bar graph that shows the data when it is broken up in to equal pieces.

Important Elements of a Histogram

Label each element on the example histogram:

• Title
• Bars
• X-Axis
• Y-Axis
• Intervals

Analyze a Histogram

The histogram shows the frequency distribution of the age of winners of the Nobel Prize in Medicine.

1. According to the histogram, most winners are between what ages when they are awarded the Nobel Prize?
2. How many people between the age 80-89 have won the Nobel Prize in Medicine?

How do you make a Histogram?

1. Collect the data
2. Create a frequency table. Choose how to divide up your data in to equal groups. These groups are called intervals. You decide what size or range for the intervals would be most best/meaningful for your data. Tally the number of items that are in each interval.
3. Create the Histogram. Create a graph with an x-axis and y-axis and label them. List the intervals on the x-axis. On the y-axis, list the tally numbers. Each interval is represented by a bar. The height of the bar tells how many of your data points fell in a given interval. Lastly give the histogram a title.

What is a histogram