Use the data from four science assignments provided in Table 2.

Table 2

Data from four science assignments

Question 1:

Enter the following data in SPSS and perform the necessary analyses in SPSS to answer the following questions.

A.  Once data have been entered, calculate descriptive statistics (central tendency and variability) for each of the assignment scores.

B.  What level of measurement do the data repre­sent (i.e., nominal, ordinal, interval, ratio)?

C.  What is the mean and standard deviation for each assignment score?

D.  What is the median for each assignment score?

E.  What is the mode for each assignment score?

F.   What is the range for each assignment score?

Question 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

Question 3

e.   Answer questions 7 through 13

A.  Determine what is unusual about student 1’s performances on the tests.

B.  What is strange about student 2’s performances? How do the performances of these two students differ, and how are they the same?

C.  What grades would be assigned to these two students if the total of the raw scores were used to determine grades?

D.  What grades would be assigned to these two students if the total of the t-scores were used to determine grades?

E.  Why are your answers to questions 9 and 10 different? (Hint: examine the variability of the tests)

F.   What are the means and the standard deviations the four z-scores distributions, to one decimal point?

G.  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 3 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.