Question

1. Compute each value requested for the following set of scores.

X

0 ΣX + 10

6 Σ(X + 10)

2 Σ(X + 1)2

3 Σ(X – 1)2 + 5

(X - X )2


2. For each of the following cases, name the observed variable and then classify (with expla- nation) the type and nature (discrete or continuous) of the scale:

a) Several respondents were interviewed and asked a few questions. For each question, their responses were coded as Strongly Agree, Strongly Disagree and No Comment.

b) A researcher is investigating the estimated time taken by students to complete an as- signment.

c) A poll studying the number of readers of three leading national news paper; Berita Ha- rian, Utusan Malaysia and New Straits Times.

d) A researcher is studying individual perception of his/her own self-esteem using a 10- point scale self-perception battery.

e) A teacher is grading her students’ academic performance into three different catego- ries: Low Achievers, Average Achievers and High Achievers


3. Identify the type of scale (with explanation) for each of the following variables: Age, gender, race, weight, hobby, happiness in life, commitment towards study


4. For the following set of scores:

5, 4, 2, 3, 4, 3, 6, 4, 2, 4, 2, 3, 5, 4, 3

a. Construct a frequency distribution table including columns for frequency, proportion, percentage, and cumulative frequency.
b. Draw a histogram showing the data.


5. A teacher conducts a test to 25 students. The scores obtained by the students are as fol- lows:

97 75 63 51 77 82 80 93 84 90
59 68 75 76 68 64 87 70 80 82
73 66 67 71 74

a) Compute the range of scores

b) Construct a frequency table based on the raw data.

Sketch a histogram and frequency polygons pertaining to it.

c) Construct a frequency table based on an appropriate grouped data (you must clarify how the data are grouped together!).
Sketch a histogram and frequency polygons pertaining to it.


6. Compute the mean, median, and mode for the set of scores shown in the following frequency distribution table.

X f
7 1
6 2
5 3
4 4
3 1
2 0
1 1


7. Calculate the variance and the standard deviation for the following sample data.

41 17 25 34 14 40 27 19 50 39
26 22 28 18 42 33 25 28 27 33
34 7 12 36 34 16 49 19 40 28
26 30 48 33 33 25 50 29 26 30