Chapter 4 How To Do Cross-Tabs In Spss 10.0/11.0

Transcription

1 How To Do Cross-Tabs In Spss 10.0/11.0 Now, let us do a cross-tabulation for population density and political complexity. To start: 1. IN MENU LINE CHOOSE: ANALYZE DESCRIPTIVE STATISTICS CROSSTABS You will see the following window:

2 2. MOVE RESPECTIVE VARIABLES TO "ROW" AND "COLUMN" BOXES. A question that might arise at this point is: "Which variable should be put in which box?" This question will have different answers depending on the following: 2a. If both variables have the same number of values, PUT INDEPENDENT VARIABLE IN THE "ROW" BOX; PUT DEPENDENT VARIABLE IN THE "COLUMN" BOX. 2b. If one variable has more values than the other, PUT THIS VARIABLE (THE ONE WITH MORE VALUES) IN THE "ROW" BOX; PUT THE OTHER VARIABLE (THE ONE WITH LESS VALUES) IN THE "COLUMN" BOX The reason for this rule is as follows: if we put the variable with many values in columns, the table will become too wide and it will be difficult (or impossible) to fit it in a standard page (in fact, we shall encounter this problem once below). In general, as the standard 2

3 Cross-Tabs in Spss orientation of paper is "portrait" ( ), rather than "landscape" ( ), it is always more convenient to deal with tables that are long, but narrow, rather than short, but wide We are going now to cross-tabulate the following variables: V64. POPULATION DENSITY and V237. JURISDICTIONAL HIERARCHY BEYOND LOCAL COMMUNITY V64 ("POPULATION DENSITY") has the following values: 1 = < 1 person per 5 2 = 1 person per = 1 5 persons per 4 = 6 25 persons per 5 = persons per 6 = persons per 7 = over 500 persons per V237 ("JURISDICTIONAL HIERARCHY BEYOND LOCAL COMMUNITY" "POLITICAL COMPLEXITY INDEX") has the following values: 1 = No levels (no political authority beyond community) 2 = One level (e.g., petty chiefdoms) 3 = Two levels (e.g., larger chiefdoms) 4 = Three levels (e.g., states) 5 = Four levels (e.g., large states) Thus, " density" variable has 7 values, whereas the "Political complexity" one has only 5. In addition to this, " density" is more likely to be regarded as the independent variable. Hence, in the present situation we have all the grounds to PUT V64 ("POPULATION DENSITY") IN ROWS, and PUT V237 ("JURISDICTIONAL HIERARCHY BEYOND LOCAL COMMUNITY") IN COLUMNS: 3

4 But after you have done this, it is still too early to click the "OK" button. So, as your next step: 3. CLICK THE "CELLS..." BUTTON. You will see the following window: 4

5 Cross-Tabs in Spss We advise you to always make crosstabs not only with observed counts, but also with percentages. As we shall see below, crosstabs with percentages are immensely more useful than the ones without them. To make a crosstab with percentages you should tick the boxes in "Percentages" part of the submenu. You can tick both "Row, and "Column, but the experience shows that in this case resultant tables are not "userfriendly. So we advise you the following: If the independent variable is in rows, tick the "Row" box; if the independent variable is in columns, tick the "Column" box! In our case the independent variable (" ") is in rows. So, tick the "Row" box. You will see the following window: 5

6 After this click the "Continue" button. After this do not forget to order the statistic analysis of the crosstab. To do this, click the "Statistics. You will see the following window: 6

7 Cross-Tabs in Spss 7

8 If you are a beginner in statistical analysis, we would advise you to tick the following boxes: Chi-square Phi and Cramer's V Correlations Gamma Kendall s Tau-b You will not necessarily need all the resultant additional tables to analyze statistically each concrete crosstab, but what you will get will be quite sufficient to answer any questions that could appear in the nearest future when you analyze crosstabs statistically. Now, press "Continue, then "OK, and you will get the following table: 8

9 Cross-Tabs in Spss * Jurisdictional Hierarchy Beyond Local Community Crosstabulation Total < 1 person / 5 1 person / persons / 6-25 persons / persons / persons / sq. mile over 500 persons / sq. mile Count Count Count Count Count Count Count Count Jurisdictional Hierarchy Beyond Local Community No levels One level Two levels Three levels Fo ,6% 16,7% 2,8% ,3% 22,7% ,0% 32,0% 16,0% 8,0% ,9% 33,3% 14,8% 18,5% ,5% 38,2% 14,7% 14,7% ,1% 31,6% 21,1% 15,8% ,8% 5,3% 26,3% 21,1% ,0% 26,4% 12,6% 10,4% As you see, even though we put in columns the variable with a smaller number of values, the resultant table does not fit a standard page. To a considerable extent this is explained by the fact that even the most recent versions of SPSS produce crosstabs with an entirely useless column ("Count vs. "). In order to make this crosstab easier to read, and more prepared for publication we would advise you to delete it. To do this double-click on the table, and block this column, e.g. pressing on any of its cells with your mouse and using the combination of "Shift" and " " buttons. After that using the mouse's left button make the column as narrow as possible: 9

10 If you click on any point outside the table now, you will see that the column has disappeared. We would also advise in this case to diminish the breadth of the second and the last column. After this the table will look in the following way: 10

11 Cross-Tabs in Spss Table 2.1: * Jurisdictional Hierarchy Beyond Local Community Crosstabulation Total < 1 person / 5 sq. mile 1 person / 1-5 sq. mile 1-5 persons / sq. mile 6-25 persons / sq. mile persons / persons / over 500 persons / Jurisdictional Hierarchy Beyond Local Community No levels One level Two levels Three levels Four levels Total ,6% 16,7% 2,8% 100% ,3% 22,7% 100% ,0% 32,0% 16,0% 8,0% 100% ,9% 33,3% 14,8% 18,5% 7,4% 100% ,5% 38,2% 14,7% 14,7% 5,9% 100% ,1% 31,6% 21,1% 15,8% 10,5% 100% ,8% 5,3% 26,3% 21,1% 31,6% 100% ,0% 26,4% 12,6% 10,4% 6,6% 100% Now, the table could be read more or less easily. However, if you are going to publish it (e.g., to use it in your essay, thesis, or article), we would still advise you to edit it. To edit an SPSS table you should first double-click on it to get into the editing mode, and then to double-click on that cell of the table which you would like to edit. For example, if you double-click on the label of the dependent variable ("Jurisdictional Hierarchy Beyond Local Community"), the table will look as follows: 11

12 We would suggest that the table which we have made should be edited in the following way: 1. The dependent variable could be more appropriately titled "Political Centralization Index = # of Political Integration Levels over Community. 2. This variable labels should be re-named accordingly. 3. Numerical values of the variable should be added. 1 As a result, the final version of the table will look as follows (see Table 2.2): 1 If you are going to use the respective database and respective variable in future, we would advise you to do corresponding changes in database itself. We would also advise you to re-code V237 in the following way: 0 = No levels (no political authority beyond community); 1 = One level (e.g., petty chiefdoms); 2 = Two levels (e.g., larger chiefdoms); 3 = Three levels (e.g., states); 5 = Four levels (e.g., large states). 12

13 Cross-Tabs in Spss Table 2.2: * Political Centralization Political Centralization Index = # of Political Integration Levels over Community Total 1 = < 1 person / 5 2 = 1 person / = 1-5 persons / 4 = 6-25 persons / 5 = persons / 6 = persons / 7 = over 500 persons / 0 = No levels 1 = One 2 = Two levels 3 = Three 4 = Four levels (Independent level (Simple (Complex levels (Small (Large states / communities) chiefdoms) chiefdoms) states) empires) Total ,6% 16,7% 2,8% 100% ,3% 22,7% 100% ,0% 32,0% 16,0% 8,0% 100% ,9% 33,3% 14,8% 18,5% 7,4% 100% ,5% 38,2% 14,7% 14,7% 5,9% 100% ,1% 31,6% 21,1% 15,8% 10,5% 100% ,8% 5,3% 26,3% 21,1% 31,6% 100% ,0% 26,4% 12,6% 10,4% 6,6% 100% And a possible final step. Normally, your essay, thesis, or article will be in Word, or other similar program. So, you may need to move the table from SPSS to Word. However, if you just copy and paste it, you will get the following: * Political Centralization Political Centralizat ion Index = # of Political Integration Levels over Communit y 0 = No levels (Independ ent communiti 1 = < 1 person / 5 Total 1 = One 2 = Two 3 = Three 4 = Four level levels levels levels (Simple (Complex chiefdoms chiefdoms (Small states) (Large states / ) ) empires) es) Count

14 2 = 1 person / = 1-5 persons / 4 = 6-25 persons / 5 = persons / 6 = persons / 7 = over 500 persons / 80,6% 16,7% 2,8% 100,0% Count ,3% 22,7% 100,0% Count ,0% 32,0% 16,0% 8,0% 100,0% Count ,9% 33,3% 14,8% 18,5% 7,4% 100,0% Count ,5% 38,2% 14,7% 14,7% 5,9% 100,0% Count ,1% 31,6% 21,1% 15,8% 10,5% 100,0% Count ,8% 5,3% 26,3% 21,1% 31,6% 100,0% Total Count ,0% 26,4% 12,6% 10,4% 6,6% 100,0% As you see, you will not get a real table, but rather a half-finished product. 2 In order to move to a Word document the whole table click on the table with the right-hand button, and choose "Copy objects" (not just "Copy"!): 2 Note, however, that the SPSS is not 100% compatible with the Word yet, so the SPSS objects sometimes "behave" in Word rather "capriciously"; hence, we advise you in certain circumstances to consider this possibility to prepare a normal Word table on the 14

15 Cross-Tabs in Spss Now you can paste it safely into a word document. Finally, for an exercise make a cross-tab for reliance on agriculture and fixity of settlement. If you follow the algorithm specified above correctly, the result should look as follows: Finally, there is a way to import a cross-tab from SPSS to Word, which preserves all the main features of the table and makes it possible to finish easily editing of a table in Word. To follow this way just choose after clicking on an SPSS table with the right-hand button "Export": basis of such half finished product, rather than to insert into a Word document an SPSS object. 15

16 After this you will see the following: 16

17 Cross-Tabs in Spss Just press "OK". By default the HTML file will be saved in the directory in which you are working. After this find file Output.htm in your working directory and open it. You will see the following: 17

18 Now press "Control-A" to select the table, copy it and paste it in a Word document with which you are working. If everything has been done correctly, the size of font and the table can now be adjusted to fit the page, and the adjusted table should look as follows: Agriculture-Contribution to Local Food Supply * Fixity of Settlement Cross tabulation Fixity of Settlement Agriculture- Contribution to Local Food Supply Total None Non-Food Crops < 10% Migratory Seminomadicfixed then migratory Rotating among 2+ fixed Semisedentaryfixed core, some migratory Impermanentperiodically moved Permanent Total ,7% 28,6% 5,7% 11,4% 8,6% 100,0% ,7% 33,3% 100,0% ,9% 35,3% 5,9% 5,9% 100,0% < 50% < single source 25,0% 16,7% 16,7% 8,3% 33,3% 100,0% < 50% > single source 4,8% 11,9% 14,3% 69,0% 100,0% Primarily agricultural ,3% 1,3% 1,3% 10,4% 85,7% 100,0% ,1% 11,3% 3,2% 7,5% 8,1% 54,8% 100,0% 18

19 Cross-Tabs in Spss Now you can easily finish the editing of the table any way you like using just standard Word menu. Note that importing a cross-tab to Word this way you will spend much less time and effort editing the table than when you just copy it directly from SPSS, which is what you see in the following table. Agriculture-Contribution to Local Food Supply * Fixity of Settlement Crosstabulation Agriculture-Con tribution to Local Food Supply Total None Non-Food Crops < 10% < 50% < single source < 50% > single source Primarily agricultural Fixity of Settlement Semisede ntary-fixed core, some Imper manent -periodi cally Seminom adic-fixed Rotating Per Migra then among man tory migratory 2+ fixed migratory moved ent Total % 28.6% 5.7% 11.4% 8.6% 100% % 33.3% 100% % 35.3% 5.9% 5.9% 100% % 16.7% 16.7% 8.3% 33% 100% % 11.9% 14.3% 69% 100% % 1.3% 1.3% 10.4% 86% 100% % 11.3% 3.2% 7.5% 8.1% 55% 100% However, though by now we know quite a lot about the relationship between the variables of consideration, we have not tested the respective hypothesis statistically. In the next chapter we shall try to explain to you how to do this. 19