## BIG IDEAS:

(taken from “Big Ideas by Dr. Small”):

1. To collect good first-hand data, you must decide what collection method is most suitable and how to best pose any questions required to collect the data.
2. To collect good second-hand data, you must be very clear on what you want to know and what source can be trusted to provide data.
3. Sometimes a large set of data can be usefully described using a summary statistic, usually a single meaningful number that describes the entire set or a combination of different statistics. The number might describe the values of individual pieces of data and/or how the data is distributed or spread.
4. Graphs are powerful data displays since visual displays quickly reveal information about data.
• Pictographs, bar graphs, histograms, and stem-and-leaf plots are particularly useful for comparing the frequency of data in different categories.
• Circle graphs are particularly useful for comparing the frequency of data in one category to the entire set of data, while still allowing for comparisons among categories.
• Line graphs and scatter plots are particularly useful for showing relationships between two quantities and trends.
5. How the data is graphed (e.g. the use of different scales or intervals) can affect what conclusions are drawn from the data.

## STUDENT LEARNING GOALS:

GOAL #1: I can collect unbiased primary and secondary, qualitative and quantitative, discrete and continuous data.

GOAL #2: I can draw and read a variety of graphs, including circle graphs. I can choose the most appropriate graph for a set of data.

GOAL #3: I can make conclusions and predictions from data in tables and graphs.

GOAL #4: I can find the central tendency of a data set.

## CURRICULUM EXPECTATIONS:

• Collect and organize categorical, discrete, or continuous primary data and secondary data and display the data using charts and graphs, including relative frequency tables and circle graphs;
• Make and evaluate convincing arguments, based on the analysis of data;
• Collect data by conducting a survey or an experiment to do with themselves, their environment, issues in their school or community, or content from another subject and record observations or measurements;
• Collect and organize categorical, discrete, or continuous primary data and secondary data (e.g., electronic data from websites such as E-Stat or Census At Schools) and display the data in charts, tables, and graphs (including relative frequency tables and circle graphs) that have appropriate titles, labels (e.g., appropriate units marked on the axes), and scales (e.g., with appropriate increments) that suit the range and distribution of the data, using a variety of tools (e.g., graph paper, spreadsheets, dynamic statistical software);
• Select an appropriate type of graph to represent a set of data, graph the data using technology, and justify the choice of graph (i.e., from types of graphs already studied);
• Distinguish between a census and a sample from a population;
• Identify bias in data collection methods;
• Read, interpret, and draw conclusions from primary data (e.g., survey results, measurements, observations) and from secondary data (e.g., temperature data or community data in the newspaper, data from the Internet about populations) presented in charts, tables, and graphs (including relative frequency tables and circle graphs);
• Identify, through investigation, graphs that present data in misleading ways (e.g., line graphs that exaggerate change by starting the vertical axis at a point greater than zero);
• Determine, through investigation, the effect on a measure of central tendency (i.e., mean, median, and mode) of adding or removing a value or values (e.g., changing the value of an outlier may have a significant effect on the mean but no effect on the median;
• Identify and describe trends, based on the distribution of the data presented in tables and graphs, using informal language;
• Make inferences and convincing arguments that are based on the analysis of charts, tables, and graphs.