Cancer deaths and exposure to radioactive waste

Use this diagram to illustrate the estimate of the 3rd regn model parameter — the error standard deviation:

Drag the line to make the residual sum of squares small. Mention that the residuals are estimates of the underlying model errors, ε.

Click Least squares to dispay the best estimate of σ.

The Hanford Atomic Energy Plant in the state of Washington in the USA has been a plutonium production facility since World War II and radioactive waste is stored in nearby pits. Some radioactive waste has seeped into the Columbia River, and eight Oregon counties and the city of Portland were exposed to radioactive contamination.

The scatterplot shows ancer deaths per 100,000 residents and an index of exposure to radiation from the river that is proportional to river frontage and inversely proportional both to the distance from Hanford and to the square of the county's (or city's) average depth away from the river. The data are from the eight counties exposed to the contamination.