Find the measures of center to summarize the pounds column of the Animals Starter File, then respond to the prompts.

1 The three measures of center for this column are:

Mean (Average) Median Mode(s)

2 If we scan the dataset, we can quickly see that most of the animals weigh less than the mean weight. Why is the average so high?

3 Referring to the pounds column of the Animals dataset, fill in the blanks:

  • Outliers on the right pull the mean toward the right, causing the mean to be greater than / less than the median.
    When the mean is greater than the median, the shape of the data is skewed right / skewed left.

  • Outliers on the left pull the mean toward the left, causing the mean to be greater than / less than the median.
    When the mean is less than the median, the shape of the data is skewed right / skewed left.

4 In the dot plot below, identify which line is the median and which is the mean. Then label the lines.
Hint: You can refer to the table at the top of the page.

number line with dots above the line representing the weight of each of the animals. There is a big cluster between 0 and 17, a small cluster in the 30s and another small cluster in the 40s and individual dots spread out along the number line til a little above 120.

  • Which has more data clustered quite close to it, the median or the mean?

  • Which do you think better represents the data, the median or the mean? Why?

5 What did you learn from calculating the mode(s)?

6 Are there any measures of center that we can use for categorical data?

7 For which quantitative column(s) in the animals table do you think the modes might be a good measure of center? Why?

8 To take the average of a column, we add all the numbers in that column and divide by the number of rows. Will that work for every column?

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