1. Variables and Measurements Communication Research Syed Muhammad Jamal MS in Media and Communication Studies International Islamic University Islamabad smjamaal@gmail.com
2. Concepts and Constructs Concepts (formally developed ideas that a researcher may seek to operationalize) They are the abstract terms we employ to explain or make sense of our experience. Definition: A concept is a term that expresses an abstract idea formed by generalizing from particulars and summarizing related observations. Our understanding of the concept develops as we improve our ability to relate it to particular phenomena. Parts of Concepts: Symbol (word or term) Definition Example Height(symbol) is a simple concept from everyday experience. It is a characteristic of a physical object, the distance from top to bottom(definition). We can measure height or compare it. A height of zero is possible and height can increase or decrease over time. As with many words we use the word in several ways. Height is used in the expressions the height of battle, the height of the summer, and the height of fashion.
5. People must share an understanding of a concept in order for the concept to be useful.Example Authoritarianism It is a concept that was developed by social scientists to explain a phenomenon which came to be recognized after World War II: the state of mind that disposed individuals to accept the kind of authoritarian regime that appeared most dramatically in Nazi Germany. In this case, a number of beliefs and opinions, which appeared to be logically connected to one another and to the kind of behavior the social scientists were trying to explain, were drawn together to form a single concept—authoritarianism.
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8. Because of its abstraction, a construct usually cannot be observed directly.
9. A construct is usually designed for some particular research purpose so that its exact meaning relates only to the context in which it is found.
10. Concepts and Construct are valuable tools in theoretical research.Example The term authoritarianism represents a construct defined to describe a certain type of personality; it comprises nine different concepts, including conventionalism, submission, superstition, and cynicism. Authoritarianism itself cannot be seen; some type of questionnaire or standardized test must determine its presence. The results of such tests indicate what authoritarianism might be and whether it is present under given conditions, but the tests do not provide exact definitions for the construct itself.
11. Variables Variable (A measure on which differences in response can be established) Definition The empirical counterpart of a construct or concept is called a variable. Variables are important because they link the empirical world with the theoretical; they are the phenomena and events that can be measured or manipulated in research. Variables take on two or more values. The values or the categories of a variable are its attributes. Example Gender is a variable; it can take on one of two values: male or female. Male is not a variable; it describes a category of gender and is an attribute of the variable gender.
23. “communication” verbal and nonverbal interaction between two or more persons To fully define construct communication, definition of verbal and non verbal are needed. ‘Verbal’ written or spoken words ‘Non-Verbal’ gesture or other nonlinguistic devices ‘Interaction’ the exchange of messages Conceptual definition: verbal and non verbal exchange of messages between two or more persons.
24. Primitive Primitive term is a concept with an agreed upon meaning. Example Communication between two or more persons between two or more persons is generally agreed upon primitive term and no formal definitions are needed to explain them.
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26. The researcher must provide conceptual definition to all concepts using in problem statement to avoid confusion and misunderstanding
33. Bivariate: A proposition that discusses the relationship between two variables is called ‘bivariate’.
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35. There is a continuous increase in the urban population of Pakistan.
36. Increase in the urban population will increase illiteracy higher the increase in population—higher the illiteracy in urban area.
37. Increase in population will increase illiteracy and crime rate Increase in population—increase in illiteracy. Increase in the population– increase in the crime rate.
38. Relationship b/w VariablesCorrelation, Positive, Negative Correlation: when a proposition says that two or more variables e.g. X and Y are related, it means that they vary together. It means that X is accompanied by a change in Y and vice versa. Such variation is called correlation. Example When the population increases, illiteracy and/or crime rate also increase. The proposition can say that increase in the population, illiteracy and crime rate are correlated. If increase in the population does not influence the literacy ratio or the crime rate, these variables are uncorrelated.
39. Correlation, Positive, Negative Positive or Direct relationship: if an increase in the value of one variable is accompanied by an increase in the value of the second variables, the relationship is called positive. Similarly, if decrease in on variable is accompanied by decrease in other variable, the relationship is called positive or direct. Negative or Inverse relationship: If increase in one variable is accompanied by decrease in the second variable, the relationship is called a negative or inverse. Example Increase in education level is accompanied by an increase in the income, the relationship is positive. If increase in the education level is accompanied by a decrease in the crime rate, the relationship between the two variables is negative or inverse.
40. Scales of Measurement Most studies in the Social and behavioral sciences collect data that are in the form of numbers. Usually, it is not the actual numbers that are of interest, but what the numbers represent. Measurement is the assignment of numbers to objects or events according to predetermined rules. Because there are different rules for assigning numbers, the same number have a different meaning, depending on the rules used to assign the number. S.S. Stevens(1951) proposed four levels of measurement that differ in the assumptions that are made regarding the underlying characteristic dimensions to which the numbers apply.
41. Measurement It indicates that measurement is a doing activity—assigning numbers—which involves performing operations sequentially(following a particular order). It specifies that what you are doing must follow certain rules or a model which lays out the principles of the measurement system. Example Suppose you are measuring the variable educational attainment. You decide to use “number of years of education completed” to represent the variable of educational attainment. A person finishing elementary school would be assigned an 8 (for eight years of schooling); a person who dropped out of high school in tenth grade would be assigned a 9; a graduate of a two-year college would be assigned a 14; a holder of a master’s degree would be assigned an 18.
44. Quantitative: Reflecting the amount or extent of an attribute.We can measure gender, male or female, by assigning the number 1 to males and the number 2 to females. This is qualitative measurement as the numbers reflect the underlying dimension of gender. These numbers reflect a quality (maleness or femaleness) and don’t provide any quantitative information. We can’t say that women possess more of the quality of gender than do men because they are given a score of 2 while men are only given a score of 1.
45. Measurement With qualitative measurement the numbers are arbitrary and don’t provide any quantitative information such as rank or distance. If, in measuring gender, we arbitrarily assign the number 37 to men and the number 3.21 to women, we are still performing measurement, since different numbers still accurately reflect the different qualities. The number here function as labels.
46. Levels or Scales of Measurement Levels of measurements Categorical Numerical Nominal Ordinal Interval Ratio Scale Scale Scale Scale Researchers rely on scales of measurement to select statistical techniques. In the social sciences four types of scales for measuring a variable (two types for categorical variables, two types for numerical variables) have been delineated. These scale type ( or levels of measurement, as they are usually called) are useful in helping to classify and catalog variables in a study, as well as in designing questions to measure variables.
48. Levels of Measurements Nominal Measurement The assignment of numbers using a nominal scale is a labeling activity. When using a nominal scale, one cannot interpret the numbers as anything other than the names of things. A variable with a nominal level of measurement consists of a set of distinctive categories that imply no specific order. It is the weakest form of measurement. In it numerals or other symbols are used to classify persons, objects, or characteristics. Example In physical sciences rocks, can generally be classified into three categories: igneous, sedimentary and metamorphic. A geologist who assigns a 1 to igneous, a 2 to sedimentary, and a 3 to metamorphic has formed a nominal scale. Note that the numerals are simply labels that stand for the respective categories; they have no mathematical significance. A rock that is placed in Category3 does not have more “rockness” than those in Categories 2 and 1. Gender: Male or Female
49. Levels of Measurements An essential requirement of nominal scaling is that subjects be classified into mutually exclusive and exhaustive categories. In other words, each subject or observation is assigned to one and only one category, and all observations or subjects are classified into the specific categories. The use of a nominal scale requires a consistent application of an assignment rule. Suppose a researcher wants to indentify which set of variables predicts response to treatment. All subjects are assigned to one of to categories: responder or non-responder. According to the rule of mutual exclusivity and exhaustiveness, subjects are assigned to one or the other category, not both, and all subjects are assigned to one or the other category. The researcher must clearly define what is meant by responder versus non-responder. In this instance, a responder might be defined as someone who falls within the “normal” range of anxiety and a non-responder as someone who falls outside of this range.
50. Levels of Measurements Ordinal Measurement Variables that have two or more categories with an inherent order among them are measured at an ordinal level of measurement. Nothing is specified with regard to the distance between any two rankings i.e., this level possesses the property of equivalence. It also possesses the property of order among the categories. Any given category can be defined as being higher or lower than any other category. Example While measuring the variable “socioeconomic status” by categorizing families according to class: lower, lower middle, middle, upper middle, or upper. A rank of 1 is assigned to lower, 2 to lower middle, 3 to middle, and so forth. In this situation, the numbers have some mathematical meaning: families in category 3 have a higher socioeconomic status than families in category 2. All families placed in a category are treated equally, even though some might have greater incomes than others.
51. Levels of Measurements Interval Measurement An interval scale is a created scale that has clearly defined intervals between the points on the scale, and it has order; but it has no true zero point. It assist us in ordering things quite precisely. An interval level of measurement has separate categories, like nominal scales, and also has ordered categories, like ordinal scales; but in addition, the distance between the points on an interval scale can be determined mathematically and precisely. These are used for continuous variables that can register very small differences between categories. Example Think of a thermometer. It has lines marking off points on the scale to register the changing temperatures. However, there is no true zero point—no point at which there would be no temperature. If it is a Fahrenheit thermometer, the zero on the scale will be at 32 degrees below the freezing point of water; if it is a centigrade thermometer, the zero on the scale will be at the freezing point of water. In neither case, however, will the zero refer to a point where there is no temperature.
52. Levels of Measurements Ratio Measurement A ratio scale encompasses all the qualities of the earlier forms of scale: it must have more than one category; it must have an implicit order; it must be able to determine the exact distance between the intervals. In addition, however, it must have a true zero point. Example Income, age, number of children, or cost of housing. Your income could be zero; you might not have children; your rent could be free.
53. References Mass Media Research- Wimmer, Dominick Social Research Methods- Neuman Contemporary Communication Research Methods- Smith http://www.socialresearchmethods.net/kb/index.php http://www.une.edu.au/WebStat/unit_materials/index.htm