View
212
Download
0
Category
Preview:
Citation preview
8/15/2019 Seminar 3 Grouping Data
1/2
STATISTICS - SEMINAR 3
GROUPING STATISTICAL DATA
1. A real estate agency, located in the central area of a town, intends to open a new office in a
peripheral area. In order to study the geographical distribution of the apartments sold by the agency,
a researcher randomly selects 30 apartments sold last month. Each apartment is located in one of the
following areas: North!est "N!#, NorthEast "NE#, $outh!est "$!# and $outhEast "$E#. %hedata are presented in the following table:
Apartment Location area Apartment Location area
1 NW 16 NE
2 SE 17 NE
3 SE 18 NW
4 NW 19 NW
5 SW 20 SW
6 NW 21 NE
7 NE 22 NW
8 SW 23 SW
9 NW 24 SE10 SE 25 SW
11 NW 26 NW
12 SE 27 NW
13 SW 28 SE
14 NW 29 NE
15 SW 30 SW
a. Identify the population, the sample, the statistical unit and the &ariable. 'escribe the &ariable and
identify its measurement scale.
b. (roup the a&ailable data and graph the results.
c. 'etermine the percentage of apartments located in each area and plot the results.
). %he number of orders recei&ed by )* companies last wee+ is presented in the following table:
Company Number of orders Company Number of orders
1 3 14 4
2 5 15 2
3 1 16 3
4 4 17 0
5 4 18 2
6 4 19 0
7 2 20 5
8 5 21 4
9 3 22 2
10 6 23 3
11 4 24 3
12 5 25 1
13 1
a. Identify the population, the sample, the statistical unit and the &ariable. 'escribe the &ariable and
identify its measurement scale.
b. (roup the a&ailable data and graph the results.
c. 'etermine the relati&e freuencies and the cumulati&e freuencies and construct the relati&e
freuency distribution and the cumulati&e freuency distributions. Interpret the &alues corresponding
to the -th class.
1
8/15/2019 Seminar 3 Grouping Data
2/2
3. %he annual turno&er "thousand Euros# for *0 companies has the following &alues:
Company Annual turnover (thousand Eur) Company Annual turnover (thousand Eur)
1 ) 26 /)
2 ) 27 10-
3 / 28 13-
4 / 29 -
5 11- 30
6 3 31 /37 3 32 10*
8 11/ 33 1-*
9 - 34
10 - 35
11 /0 36 /-
12 // 37 10
13 1)3 38 1-
14 * 39
15 - 40
16 /1 41 /*
17 101 42 110
18 13) 43 1-
19 / 44 /
20 * 45 /
21 /1 46 /
22 10) 47 113
23 133 48 1-
24 ) 49 /
25 50 10)
a. (roup the a&ailable data into eual classinter&als2 graph the results.
b. 'etermine and plot the relati&e freuencies. Interpret the &alue for the second class.
c. 'etermine and plot the cumulati&e freuencies "ascending and descending#. Interpret the &alues forthe *th class.
d. ompute midpoints for the determined classinter&als.
Observation: use Excel tools for grouping the data.
-. %he length of time it ta+es to assemble a particular electronic component &aries from an employee to
another. 4anagement has collected the time "in minutes# it too+ )0 different employees to assemble
the component. %he information is summari5ed in the following freuency distributions generated by
E6cel:
Bin Frequency % Cumulatie %
10 1 7 *
1* / 7 *0
)0 1 7 **)* 7 7
4ore 7 7 100
a. 8ind the missing &alues.
b. !hich of the following statements is true:
1. It too+ *09 of all wor+ers e6actly 1* minutes to assemble the component.
). It too+ 1009 of all wor+ers longer than )* minutes to assemble the component.
3. 11 wor+ers assembled the component in )0 minutes or less.
4. It too+ wor+ers )* minutes or longer to assemble the component.
2
Recommended