Datasets for Statistical Analysis

Weight of Cherry Ripe mini-bars

Keywords:

chocolate bar; weight

Categories:

popular;
one- and two-sample data

Description:

The data give the weight of 12 individually wrapped Cherry Ripe chocolate bars. They come from a pack of 12 stating that the weight of each individual bar is 18g. The data were gathered during an introductory stats class, using a set of scientific scales (reading to 0.1 gram) borrowed from the USQ Physics labs to

• Test if the (mean) weight really is 18g;
• Form a confidence interval for the true weight.

The bars were weighted with the wrappers (for hygiene reasons). Weighing the wrappers separately gave a mean of 0.2g.

There are 12 observations on three variables.

Variables:

Name	The name
Wt	The weight of the bars plus wrapper in grams
NetWt	The weight of the bars less the wrapper weight in grams (0.2g)

Data Quality:

There are no missing values.

Source:

Collected personally by me and 11 volunteers in the class.

Notes:

I have performed this experiment many times, and am disappointed I haven't kept more data. But in every case, the sample mean was well above 18g.

References: