2.1 Frequency distribution Histogram, Frequency Polygon

Example: page 43, problem max min

-range = 7119 – 1000 = c.w. = 6119 ÷ 6 = → we will start the setup of the class limits with the minimum data value (1000), to which we will add the class width (c.w.) -this are the lower limits (where each class begins)

Class limitsTallyfClass midpoint 1000 – 2020 – 3040 – 4060 – 5080 –

-Next we determine the first class’ upper limit (where it ends) by subtracting 1 from the second class’ lower limit – 1= then we add again the class width (1020) to the upper class’ limits

Class limitsTallyfClass midpoint 1000 – – – – – – 7119

-now we evaluate the first classes midpoint by adding the two class limits and divide by = ÷ 2 = Then we add the class width to the midpoint

Class limitsTallyfClass midpoint 1000 – – – – –

-Now we tally

Class limitsTallyfClass midpoint 1000 – 2019//// //// // – 3039/// – 4059// – 5079/// – 6099/ /

HISTOGRAM -Is a bar graph with vertical bars -The bars are equal in width -The bars do touch each other -On the x-axis: class midpoint -On the y-axis: frequency -Important: label the axis, name your graph

FREQUENCY POLYGON -Is a closed shape -On the x-axis: class midpoint -On the y-axis: frequency -Important: label the axis, name your graph -Me might have to extend the marks on the x-axis to the left and/or to the right with one more class width.