The graph represents the data clearly and accurately, with the scale and intervals chosen appropriately.

The description of the grizzly bears and black bears includes accurate observations about the ranges of the two sets of data and the way each set of data is distributed over its range (that is, some comments about center and spread, although these may not be in formal statistical terms).

The general conclusion reached is that grizzly bears are generally heavier than blacks, but some blacks weigh more than some grizzlies.

A number or range is chosen that represents the difference between the central values or central clumps of the two sets of data. A median, mean, or less formal measure of center is used (e.g., "Most of the grizzly bears clump around 200 pounds even though there are a few bigger ones and a few smaller ones, so I said that a typical grizzly bear is 200 …").

Characteristics of the medium response:

The scale or intervals chosen are not chosen so as to show the data as clearly as possible, or there are a few inaccuracies in plotting the data.

The description of the blacks and grizzlies does not include some of the important aspects about the range and center of the data.

The general conclusion reached could be interpreted to mean that all grizzlies weigh more than all blacks (that is, the overlap of the data is not noted).

A reasonable answer is given (that a typical grizzly bear weigh about 30 to 50 pounds more than a typical black bear) but the explanation is inadequate.

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement