In this activity, students learn some of the pitfalls of doing surveys.They also learn to examine the shape of data, including data clusters,the range and typical values. This Cyberchase activity is motivated by a video segment in which the CyberSquad searchesfor Hacker's castle based on a survey of where town residents have lastseen him.
Using Data Clusters to Find Hacker QuickTime Video
Part I: Learning Activity
1. Tell the students that the CyberSquad is trying to locate Hacker'scastle, where Dr. Marbles is hidden. In Castleblanca, there are toomany castles to check, so the CyberSquad conducts a surveyasking people to put a mark on a map where they have seen a tall manwith a pointy chin and cape. Based on the data, they find Draculanot Hacker.
2. Tell the students that they will see a video segment in which theCyberSquad tries to figure out how to find Hacker instead of Dracula.
3. Show the Using Data Clusters to Find Hacker QuickTime Video, andask students to keep track of as many things as they can, which canmake one's data set lead to the wrong predictions or conclusions.
4. Discuss the students' ideas.
5. Distribute the Handout: "What's Typical, Based on the Shape of Data Charts?".
6. Ask students to examine the data collected by Inez and Matt and to answer the questions.
7. Discuss their answers, noting that the two data sets differ onlyby one inch, suggesting perhaps that one kid measured the band memberswith their shoes on and one kid measured them with their shoes off.This is a systematic error in data collection.
Part II: Assessment
Assessment: Level A (proficiency): Students are asked to examine a table of data showingthe average number of hours of sleep for males and females in differentage groups, and to identify the range, mode, and some othercharacteristics of the data set.
Assessment: Level B (above proficiency): Students are asked to examine a scatter plot ofdata showing records of the speed of cars and the time of day they wererecorded along a certain stretch of road, to identify clusters of data,and to decide when it would be best to set up a speed trap.