Data sources and data Types of stat.pptx

introduction for stat

1. Data Sources and Data Types

2. A marketing research analyst needs to assess the effectiveness of a new television advertisement A pharmaceutical manufacturer needs to determine whether a new drug is more effective than those currently in use. An operations manager wants to monitor a manufacturing process to find out whether the quality of the product being manufactured is conforming to company standards. An auditor wants to review the financial transactions of a company in order to determine whether the company is in compliance with generally accepted accounting principles. 13 Why Collect Data

3. Primary Sources: The data collector is the one using the data for analysis Data from a political survey Data collected from an experiment Observed data Secondary Sources: The person performing data analysis is not the data collec tor Analyzing census data Examining data from print journals or data published on the internet. Sources of Data

4. 6 Variables A variable is a characteristic or condition that can change or take on different values. Most research begins with a general question about the relationship between two variables for a specific group of individuals.

5. Types of Variables Variables Qualitative/ Categorical Quantitative Continuous Discrete Nominal Ordinal/ Rank Grades pH level Risk level Names Colors Telephone No Grade ‘A’, ‘B’, ‘C’ Cost No of Boys No of books Names Colors Telephone No Describe Names or Category Categorization Weakest data measurement Numbers used to label an item, Catego Used Ranke data Can be verbalized excellent, good, Fair, poor Distance between rank can not measured A variable that takes values from a finite or countable set A variable that can take on any of a range of values. Body Temperature Mass Distance variables have values that represent quantities . variables have values that can only be placed into categorie s

6. Levels of Measurement Nominal classifies data into distinct categories in which NO ranking is implied Ordinal classifies data into distinct categories in which ranking is implied is an ordered scale in which the difference between the measurements is a meaningful quantity and the measurements have a true zero point Ratio Interval is an ordered scale in which the difference between measurements is a meaningful quantity but the measurements DO NOT have a true zero point . The Scale of measurement determines the amount of information contained in the data and indicates the most appropriate data summarizing and statistical analysis

7. Types of Measurement Scales A nominal scale is an unordered set of categories identified only by name. Nominal measurements only permit you to determine whether two individuals are the same or different. An ordinal scale is an ordered set of categories. Ordinal measurements tell you the direction of difference between two individuals. How satisfied are you with our services? 1 Very Unsatisfied   2 Unsatisfied   3 Neutral   4 Satisfied   5 Very Satisfied  

8. Interval scale Interval scale offers labels, order, as well as, a specific interval between each of its variable options. Interval Scale  is defined as a numerical scale where the order of the variables is known as well as the difference between these variables. Variables that have familiar, constant, and computable differences are classified using the Interval scale. It is easy to remember the primary role of this scale too, ‘Interval’ indicates ‘distance between two entities’, which is what Interval scale helps in achieving.  

9. Example- Interval scale Celsius/Fahrenheit temperature scale 80 degrees is always higher than 50 degrees and the difference between these two temperatures is the same as the difference between 70 degrees and 40 degrees. Time - the values are already established, constant, and measurable. Calendar years and time Income of a person

10. 15 Types of Measurement Scales 3. An interval scale is an ordered series of equal-sized categories. Interval measurements identify the direction and magnitude of a difference. The zero point is located arbitrarily on an interval scale. 4. A ratio scale is an interval scale where a value of zero indicates none of the variable. Ratio measurements identify the direction and magnitude of differences and allow ratio comparisons of measurements.

11. Ratio scale Ratio scale bears all the characteristics of an interval scale, in addition to that, it can also accommodate the value of “zero” on any of its variables. Ratio scale provides the most detailed information as researchers and statisticians can calculate the central tendency using statistical techniques such as mean, median, mode, and methods such as geometric mean, the coefficient of variation, or harmonic mean can also be used on this scale.

12. Example- Ratio scale Weight and height of person. Annual sales, The price of products, The number of consumers, etc. https://www.questionpro.com/blog/nominal-ordinal-interval-ratio/