Data and Probability in Upper Elementary School

The study of statistics has gone from being a university course, to an elective course in high schools, to being a large part of the study of mathematics at all levels, all within the past ten years.This is a reflection of the changing role of mathematics in society and especially the increasing importance of quantitative reasoning in decision making in business and government. 

The study of statistics in the Atlantic provinces is outlined in GCOs F and G of the APEF mathematics curriculum. 

Activities

HTML versions Word Versions

 
 

Resources

Background

Curriculum Outcomes




Resources

http://forum.swarthmore.edu/probstat/probstat.html


Articles in Teaching Mathematics in the Middle School (in Acadia’s library)

Articles in Teaching Children Mathematics (aka, the Arithmetic Teacher, in Acadia’s library)


 

Background

Averages:What are they and what are they for?
·Mean- if the total were evenly distributed, everyone would have this amount
·Median- if everyone is ranked the person in the middle has this amount

·Mode- most people have this amount

The mean is the most commonly use average. It is appropriate for numerical data in which every number is possible.Use with data that include outliers can be misleading. Measurements are often averaged using the mean.
 

The median is useful for numerical data where not every number is possible, or where there are outliers.  Income data (which often has outliers) is often averaged using the median.Data from Likert scales should also be averaged using the median (but sloppy social scientists often use the mean).
 

The mode is the only average you can use with non-numerical categorical data.If you wanted to average “Favouritecolour” you’d use the mode.


 
 

Measures of dispersion: What are they and what are they for?
 

·Maximum (plural maxima) refers to the largest value in the data

·Minimum (plural minima) refers to the smallest value in the data

·Range refers to the difference between the maximum and the minimum.The bigger the range the more dispersed (spread out) the data is. If the data is widely dispersed then few values will be close to the mean and median.

·Frequency refers to the number of times each value occurs in the data.If the frequencies are all about the same them the data is more dispersed than if there are a few values of high frequency close together.
 

All of these are used to decide if an average is a good representation of the whole data set. If the data is widely dispersed then the average doesn’t tell you much about most of the data.The class average might be 75%, but if the range is big and the frequencies are small, then most people don’t have marks of about 75%.On the other hand if the range is small and the frequencies relatively high, then most people probably do have marks close to 75%
 

Graphs and plots: What are they and what are they for?


 
Pictographs display categorical data by representing each member (or groups of n members) of a category with a picture of it.

Preferred means of communication


 
Letters
Phone calls
Emails
Bombs thrown

Line graphs represent categorical data by representing the total number of members with a point, and joining the points.It is often used to trace events over time.
Bar graphs display categorical data using bars to represent the total number of members in each group. 

Double bar graphs are used when two sets of data are being compared.


 
Stem-and-leaf plots are useful for displaying the distribution of numerical data, and displaying the data at the same time.


 
Final marks
6
7
8
9
7889
13356788
00234445677788889999
0000001111122333467

Circle graphs are used to display proportional data where the amount in each category is compared to the total.
Coordinate graphs are used to display the relationship between two sets of numbers.

Scatter plots are used to display data so a judgment can be made about whether or not there is a relationship between two sets of numbers.

Curriculum outcomes (GCOs F&G) 


Grade 4

F1- recognize and use a variety of methods for the collection and organization of data

F2- describe data maxima, minima, range and frequency

F3- read and interpret bar graphs, line graphs, pictographs, and stem-and-leaf plots

F4- display position, using ordered pairs on a grid

F5- construct bar graphs, pictographs, and stem-and-leaf plots

F6- interpolate data from a display

F7- describe data, using the mean

F8- explore real-world issues of interest to students and for which data collection is necessary to determine an answer

G1- predict probabilities as either close to 0, near 1, or near ½

G2- cite examples of everyday events with very high or very low probabilities

G3- predict whether one simple outcome is more or less likely than another

G4- use fractions to describe experimental probabilities

Grade 5

F1- use double bar graphs to display data

F2- use pictographs and bar graphs to display and interpret data

F3- use coordinate graphs to display data

F4- create and interpret line graphs

F5- groups data appropriately and use stem-and-leaf plots to describe the data

F6- recognize and explain the effect of certain changes in data on the mean of that data

F7- explore relevant issues for which data collection assists in reaching conclusions

G1- conduct simple experiments to determine probabilities

G2- Determine simple theoretical probabilities and use fractions to describe them

Grade 6

F1- choose and evaluate appropriate samples for data collection

F2- identify various types of data sources

F3- plot coordinates in four quadrants

F4- use bar graphs, double bar graphs and stem-and-leaf plots to display data

F5- use circle graphs to represent data proportionally

F6- interpret data represented in scatter plots

F7- make inferences from data displays

F8- demonstrate an understanding of the differences among mean, median, and mode

F9- explore relevant issues for which data collection assists in reaching conclusions

G1- conduct simple simulations to determine probabilities

G2- evaluate the reliability of sampling results

G3- analyze simple probabilistic claims

G4- determine theoretical probabilities

G5- identify events that could be associated with a particular theoretical probability


[Copyright -- David A Reid] [School of Education] [Acadia University]