Worlds of Data

Our personal worlds of home, school, work, and play take direction and stay afloat on a river of data-filled information—data about money, time, weather, test scores and grades, game scores and standings. Similarly, our public worlds including society, the nation, and the world surround us with data about the economy and the environment, politics, cultures, science, and history.

Understanding and living successfully in our worlds depend in a large part on understanding and working effectively with the data and data systems of those worlds. We need—

• to read data accurately (to know numbers’ values, to distinguish percentage points from decimal points and whole numbers from fractions);
• to place data in appropriate contexts and relationships (to distinguish money numbers from measurement numbers, exact numbers from approximate numbers);
• to use data to infer and predict (to understand the effect of a 15% drop or rise in price, population, temperature, opinions);
• to evaluate data and make judgments based on its reliability (to get beyond numbers as facts to numbers as indicators and evidence);
• to recognize manipulated data (to tell the differences between statistical truth and statistical half-truths and lies).

The importance of working with data is reflected in the NCTM Principles and Standards:

The amount of data available to help make decisions in business, politics, research, and everyday life is staggering: Consumer surveys guide the development and marketing of products. Polls help determine political campaign strategies, and experiments are used to evaluate the safety and efficacy of new medical treatments. Statistics are often misused to sway public opinion on issues or to misrepresent the quality and effectiveness of commercial products. Students need to know about data analysis and related aspects of probability in order to reason statistically—skills necessary to becoming informed citizens and intelligent consumers.

(NCTM 2000, 48)

Unlike practice in many countries, NCTM proposes a Data Analysis and Probability Standard that spans the grades. From prekindergarten to grade 12, the standard proposes an emphasis on “gathering and using data wisely” and “reasoning about data and statistics [that] will serve students well in work and in life” (NCTM 2000, 48).

Students develop statistical reasoning skills as they “work directly with data” (NCTM 2000, 48). They learn how to collect and organize, display and analyze data and in the  process how to interpret and use data to make decisions and predictions and to answer the question “What are the meanings of the data in my life?”