section 2.2b graphical displays of distributions
TRANSCRIPT
StatisticsChapter 2 Exploring Distributions
Section 2.2bGraphical Displays of Distributions
Low Temperature DataState Low Temp. Year State Low Temp Year State Low Temp YearAL -27 1966 LA -16 1899 OK -27 1930AK -80 1971 ME -48 1925 OR -54 1933AZ -40 1971 MD -40 1912 PA -42 1904AR -29 1905 MA -35 1981 RI -23 1942CA -45 1937 MI -51 1934 SC -19 1985CO -61 1985 MN -59 1903 SD -58 1936CT -32 1943 MS -19 1966 TN -32 1917DE -17 1893 MO -40 1905 TX -23 1933DC -15 1899 MT -70 1954 UT -69 1985FL -2 1899 NB -47 1899 VT -50 1933GA -17 1940 NV -50 1937 VI -30 1985HA 12 1979 NH -46 1925 WA -48 1968ID -60 1943 NJ -34 1904 WV -37 1917IL -35 1930 NM -50 1951 WI -54 1922IN -36 1994 NY -52 1979 WY -66 1933IA -47 1912 NC -34 1985KS -40 1905 ND -60 1936KT -37 1994 OH -39 1899
• Fully describe the distribution of this data.
Practice Problems
D8 – What information is lost when you use a relative frequency histogram.
P6 Refer to page 5 Display 1.1 Which variables are quantitative and
which are categorical P8 Make histograms of data for
average longevity and then max longevity from display 2.24. Describe differences in shape, center, spread. Why do these occur.
Practice Problems
P8 Convert the frequency histograms into relative frequency histograms.
P10 Using Rel Freq Hist from 2.28 on p. 47. Estimate the proportion of mammals
with a life expectancy of less than 50 years.
Describe the shape of the distribution Estimate the median of this distribution
Stem-and-Leaf (Stemplots)
Shows distribution much like Dot Plots and Histograms, but uses a different method.Key 3| 9 is 39 years of age
0 1 2 4 5 51 0 1 2 2 2 2 3 4 3 0 0 3 3 4 6 8 94 0 1 1 2 35 06 178 2 3
Stemplots
You can also use to compare two data sets back to back.
Group #2 Group #14 3 0 2 4 5 6
9 9 5 1 2 2 3 5 7 8 9 93 2 1 1 2 1 1 2
3 2 2 3 0 14 0
2 5 1
Stemplots
Use with relatively small amount of data
You want to see individual values You want to find mean, median or mode
You want to compare 2 groups (back to back)
Bar Charts
Use with categorical data
The horizontal axis is where you list the categories.
The bars are then used just like a histogram
There is typically a separation between the bars.
Bar Chart Example
1 Group Comparison of 2 Groups
Homework
Stats Page 53 E15, 20, 21, 22, 23, 25
AP Page 53 E15, 23, 24, 25
Read Section 2.3