Note: From no. 4 on, there are valid assignments for 2015 (originally, they are from 2014).

**Back to the main page** Quantitative Data Analysis I. (presentations, readings, etc.)

What we have done QDA II. 2015 - summer semester

Homework must be writen in doc MS Office format (possibly in txt, rtf or pdf) with your answers to the questions and brief interpretation of the results (select only adequate results from SPSS output).
Send it to the email jiri.safrATseznam.cz; in the subject, please write: QDA2, homework NO., YOUR NAME |

0. (18/2/15) No homework (in fact, there was no class due to the bomb alarm) except for filling in knowledge of survey design by reading handouts and literature on **metodykv.wz.cz** and elsewhere.

Get Data

Examine all basic variables (from

For appropriate range of values see questionnaire (ppt) + common sense! (e.g. a day has only 24 hours ...).

Make tables of frequencies (FREQUENCIES). Show - paste them into MS Word document (doc) with raw data (not cleaned yet) and right after it if relevant (where you defined any missing value) show the table again after cleaning it (defining missing values) and try to comment the result but only very briefly. Attach adequate syntax commands (it can be on the whole in the appendix). If you are still not able to work with syntax commands and you are using menu + mouse, never mind, document your work of "data cleaning" on the tables before/after defining missing values by words.

Don't forget to state in the subject of your email : QDA1, Homework 1,

Instructions and some clue: Principle of MISSING VALUES command as well as making descriptive tables (FREQUENCIES) can be found in
**Syntax 11/3/2015** and **Syntax 18/3/2015** or in an older Syntax 5/3/2014

Everything is explained in the presentation 2. **Missing Values: identification, assigning and their analysis** (1.) (slides 2-14) See also 1.** Introduction to SPSS/PSPP (1.)** (program environment, data input, labelling variables, basic settings) and you can also watch a video **Intro to SPSS** (the very basics) and read **SPSS Statistics for Students: The Basics** (very helpful guide at SSCC University of Wisconsin - Madison)

Calculate descriptive statistics (mean, standard deviation, median, or percent and mode) for the variables: Gender [

Everything is explained in the

Beware of "inadequate" values (First, check out whether you have set them as MISSING). Insert Tables form the SPSS output into the MS Word document (here are instructions/tricks on SPSS-doc) and comment the results briefly sociologically. Also add commands in the syntax which you have applied.

Compute mean and standard deviation in two groups of HiSO students of AKD1 2013: Daily (denní) and Distant (kombinované) studium:

1. by hand (paper/pencil - MS word, calculator), 2. in MS Excel or other spreadsheet program (by setting function into cell) and finally after you copy data into SPSS) in SPSS, here you also compute median and graphs Histograms. (notice results for StDev should be similar but not necessary the same.)

DATA (also in

Daily studium (age):

Distant studium (age):

All 3 computations/outputs put into the word document (computation by hand, Excel table or printscreen of the sheet at least, SPSS table and picture-graph), don’t forget to add small interpretation of difference between the two classes (values distribution using mean, median, stddev).

Everything is explained in

(so far updated for summer 2015)

For assignments 4. to 8. there are help links to SPSS syntaxes we did in 2014.

Bivariate analysis of means of ratio (numeric) variable in categories of categorical variable.

When interpreting the results for Class [

First before computing means, examine values of the dependent variables (check it by Frequencies and possibly set "deviant values" to user MISSINGS) and also beware of sufficient number of cases in the subgroups when interpreting means.

Everything is explained in the upgraded

Data

Recoding of ratio (numeric) variable into categories and

Recode – collapse the ratio (numeric) variable watching television (in hours/a day) [

Recoding ratio variable is explained in the upgraded

Data

Make two contingency tables for categorical dependent variable Total books read and categorical explanatory variables: a) Watching TV, and b) Number of friends.

First, create a categorical variables [

Is the number of books read related to watching television and to a number of friends? Interpret the results sociologically. And are result the same as in task 5, where the dependent variables

(Use the command CROSSTABS with the COLUMN percent. It is explained in the upgraded

Data

Make a contingency table for the dependent variable Total number of books read (tertiles [

What is the relationship between the total number of books read and watching TV respectively number of friends you already know from the previous homework, it is sufficient to copy the tables and the result (watch the same number of cases for the current data size it is n = 128). And newly add the answer to the question: Are these relationships (Books-TV and Books-Friends) the same for men and women? At the same time when interpreting the 3-rd level describe which group reads the least and which the most (combination of sub-grouping: TV x Gender and Gender x Friends).

In sum, construct two contingency tables (just copy those from the previous homework) and two new tables extended with the third controlling variable – gender. Interpret the results sociologically.

In SPSS use the command CROSSTABS (again, with column percent) + adding a third controlling variable; see

How to format tables, present and interpret the relationships between variables in contingency table see examples in

First, recode the original ordinal variable [

Make a contingency table for dependent variable [

What is the relationship between the frequency of reading books and age? Is this relationship somehow modified by education? Or is it the same in all three educational levels? When interpreting results use the differences in percentage points between categories and also coefficients of association/ordinal-correlation. Further describe which group reads the least, and the most (combination: Age4 x edu3). Interpret the results sociologically.

In sum, you will construct two tables: bivariate and trivariate (with controlling variable – factor – education) and their appropriate coefficients associations/correlations for general zero-order association and then for partial associations.

In SPSS use the command CROSSTABS (again, with column percent and ordinal correlation Gamma) + adding a third controlling variable; see

How to format tables, present and interpret the relationships between variables in contingency table see examples in

And don't forget to state in the subject of your email: QDA1, Homework
NUMBER, YOUR NAME |

References:

Babbie, E. 1995.

de Vaus, D., A. 1985.

Treiman, D. J. 2009.