Day 1 - Team B

Day 1 Blog

SPSS (originally Statistical Package for Social Sciences) is a comprehensive statistical analysis tool. It is used extensively to generate tabulated reports and charts among others, which help businesses, identify industry trends and make decisions.

Types of Variables in SPSS

Category Variable

·         It is that type of variable which can take limited of fixed number of possible values. For instance, blood group of a person (A, B, O, AB), months in an year (only 12 possible values),states in a country etc. Generally, they are represented on a nominal scale, and given their nature, these can be at best categorised by the mode as a measure of central tendency. E.g.: there cannot be any average blood group in a group of people.

    Continuous Variable

·         These types of variables can have infinite number of different values. For instance, height or weights of persons can have unlimited number of possibilities. Within continuous variables, discrete (or whole numbers) would mean that while the variable have fixed values that can’t be specified in decimals. E.g. number of kids in a family, cars owned by a family.

Types of Measures used

·       

       Nominal Data: This allows for only qualitative classification. It gives the user the freedom to assign a number to the data. This type of data classification is qualitative in nature. The data thus represented has no order. While the data is categorised and coded, it can’t be ranked.

Nominal codes can be multiple

Male	1	21	16
Female	2	22	15

·        

   Ordinal Data: It differs from nominal data in the sense that data is ranked and ordered in a meaningful sequence. While this data has order, the intervals/ difference between scale points may be uneven and can’t be quantified. Example, in a census, ‘upper middle’ class is higher than ‘middle’ class, but by how much can’t be ascertained.

Upper Middle Class	1
Middle Class	2
Lower Middle Class	3
Lower Class	4

·         Scale Data: In this type of data grouping, data is not only ranked, but the difference can also be ascertained. It is

Descriptive Statistics in SPSS

·     Frequencies: It is used primarily for nominal and ordinal data. Tells the number of times the variable has occurred.

·     Cross Tabulation: It is a process by which two or more data variables are tabulated, and displays the relationship in a tabular form. Generates information about bi-variate relationships. It is not suitable for continuous variables that assume multiple values. In such a case, these continuous variables are re-categorised into category variables.

For example: Age can be 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27 and 28 years. The task is to find out how many marry before the age of 20 years. Depicting this data in a cross tabulated form can be very tedious. Thus it can be re-categorised in to age groups 14-20 and 21-28. 

By

--Neeraj Gandhi

--Siddhartha Srinivas Ippaka