# Instructions The goal of this assignment is to explore the concepts related to t

Instructions
The goal of this assignment is to explore
the concepts related to the normal curve and standard scores. Furthermore,
another goal is for you to explore the various tools for data analysis in the
SPSS software. These tools include the compute and standardize
scores functions. You will find the steps in the assignment
instructions to use these tools.
Use the data from four science assignments
provided in Table 2.
Table
2
Data
from four science assignments
Student
A1
A2
A3
A4
1
97
28
89
9
2
94
86
80
39
3
95
80
82
10
4
97
39
83
14
5
96
60
87
38
6
95
42
84
34
7
94
38
85
31
8
95
60
85
21
9
98
62
84
12
10
96
51
83
20
11
96
53
86
38
12
98
32
85
27
Part I:
Please enter the following data in SPSS and
perform the necessary analyses in SPSS to answer the following questions.
1. Once
data have been entered, calculate descriptive statistics (central tendency and
variability) for each of the assignment scores.
2. What
level of measurement do the data repre­sent (i.e., nominal, ordinal, interval,
ratio)?
3. What
is the mean and standard deviation for each assignment score?
4. What
is the median for each assignment score?
5. What
is the mode for each assignment score?
6. What
is the range for each assignment score?
Part II:
a. Your
first task is to obtain a total assignment score for each student. To obtain
the total score (“totscore”), you will use the compute tool in
SPSS. To do this, in the top menu click on Transform, then Compute.
o
A compute
variable box will appear, where you can type in a formula for the
program to calculate.
o
In
the target variable box, enter “totscore.” Then, click once in
the numeric expression box.
o
After
that, double click on Assignment 1, to move it from the list of
variables to the numeric expression box.
o
Then
click on the + (plus) sign.
o
After
that, double click on Assignment 2 and follow the same
instructions as Assignment 1 for the rest of the assignments. This new variable
is the total sum of the four assignment scores.
b. The
second step is to calculate a z-score for each of the assignments and the total
score.
o
To
create the z-score in SPSS, you will go to analyze, then descriptive
statistics, and descriptive.
o
Include
in the window the four assignments and the “totscore” variables. Then check the
box on Save Standardized Values as Variables.
c. The
third step is to convert each of the scores to a t-score.
o
The
equation to a t-score is 50+(10*z-score). To convert the scores to t-score you
will use the compute tool again.
o
To
do this, in the top menu click on Transform, then Compute.
o
A compute
variable box will appear, where you can type in a formula for the
program to calculate.
o
In
the target variable box, enter the t-score1.
o
In
the numeric expression box, enter the t-score equation
50+(10*ZA_1) and use each appropriate z-score for each assignment. You also
need a total t-score (tot_tscore) for each student.
o
Use Transform,
then Compute.
o
Enter
(tot_tscore) as the target variable and insert a formula in the Numeric
Expression window to sum the four t-scores.
d. In
a separate document (Word or Excel), create two columns to compare the
totscores (total scores) and the tot tscores (total t-scores). Please use the
following grade breakdown to rank the assignment grade scores 1 through 12,
where 1 is the highest score A, and 12 the lowest score F:
o
A
to rank 1
o
B
to rank 2
o
B–
to rank 3
o
C+
to rank 4
o
C
to ranks 5, 6, 7, and 8
o
C–
to rank 9
o
D+
to rank 10
o
D
to rank 11
o
F
to rank 12
questions 7 through 13
7. Determine
what is unusual about student 1’s performances on the tests.
8. What
is strange about student 2’s performances? How do the performances of these two
students differ, and how are they the same?
9. What
grades would be assigned to these two students if the total of the raw scores
10. What
grades would be assigned to these two students if the total of the t-scores
11. Why
are your answers to questions 9 and 10 different? (Hint: examine the
variability of the tests)
12. What
are the means and the standard deviations the four z-scores distributions, to
one decimal point?
13. What
are the means and standard deviations of the four t-score distributions, to one
decimal point?
Length: Complete responses to all parts of
all 13 questions. Please include the question prompts along with your responses
in your assignment submission. In addition to a WORD (.doc) file with the
answers to the assignment questions, also include the output (.spv) file. (NOTE:
SPSS automatically generates the .spv file as you work in SPSS. When you close
your SPSS main window, SPSS will ask you if you want to save the output file. 