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Page 1

  • Data analysis includes the attribute salary

    • Values for salary: 30, 36, 47, 50, 52, 52, 56, 60, 63, 70, 70, 110

  • Mean: 58

  • Median: 54

  • Mode: 52

  • Midrange: 140 - 30 = 110

  • First Quartile (Q1): 48.5

  • Third Quartile (Q3): 66

  • Boxplot: 30, 48.5, 54, 66.5

Page 3

  • Data collection is gathering information about a subject

  • Importance of complete and ethical data collection for accurate analysis

Page 4

  • Primary data: collected firsthand, costly, through observations, surveys, etc.

  • Secondary data: already collected, affordable, from various sources, may not meet current research purpose

Page 6

  • Data collection methods include surveys with unbiased questions

  • Types of surveys: online, face-to-face

  • Questionnaire administration methods: mailed, collective

Page 8

  • Questionnaire types: closed-ended, open-ended

  • Forms of questions in a questionnaire

  • Advantages and disadvantages of questionnaires

Page 10

  • Data collection methods: Transactional Tracking, Interviews, Focus Groups

  • Transactional Tracking for targeted marketing decisions

  • Interviews and Focus Groups for qualitative and quantitative data

Page 11

  • Data collection methods: Observation, Online Tracking, Forms

  • Observation for real-time user interaction insights

  • Online Tracking for behavioral data gathering

Page 12

  • Observational methods involve looking and listening carefully

  • Types of observation: Structured, Unstructured, Participant, Non-participant

Page 13

  • Structured Observation: planned in advance, useful for large-scale studies

  • Example: patient reaction to hospital in different phases

  • Advantages and disadvantages of Structured Observation

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  • Unstructured Observation: no advance design, observer decides on the spot

  • Example: observing a child playing with a new toy

  • Strengths and weaknesses of Unstructured Observation

Page 16

  • Participant Observation

    • Observer is actively present in the observed setting.

    • Advantage: Allows for clarification and interaction with people.

    • Disadvantage: Inexperienced observer may miss relevance and influence behavior.

Page 17

  • Non-participant Observation

    • Observer remains detached and only observes.

    • Strength: Collects information without being influenced.

    • Example: Plainclothes policemen at public events.

Page 18

  • Sampling

    • Primary data collection when secondary data are unavailable.

    • Population Method (Census Method) vs. Sample Method.

    • Population classified as Finite or Infinite, Real or Hypothetical.

Page 19

  • Classification of Population

    • Finite Population: Countable elements.

    • Infinite Population: Uncountable elements.

    • Real vs. Hypothetical Population.

Page 20

  • Merits and Demerits of Census Method

    • Data from every unit of the population.

    • Representative and reliable data.

    • Intensive study possible.

    • Time-consuming and costly.

    • Not suitable for all research types.

Page 21

  • Sampling Population

    • Learning about the population through a sample.

    • Steps in sampling framework for making inferences.

Page 22

  • Sampling Frame

    • Certain groups of interest within the population.

    • Relationship between Population, Sampling Frame, and Sample.

Page 23

  • Methods of Sampling

    • Statistical data collection through various methods.

    • Includes Convenience, Simple Random Sampling, Cluster Sampling, etc.

Page 24

  • Probability Sampling Methods

    • Every member has a chance of selection.

    • Used in quantitative research to eliminate bias.

Page 25

  • Simple Random Sampling

    • Every item in the population has an equal chance of selection.

    • Steps for minimizing biases in the sampling process.

Page 26

  • Simple Random Sampling Example

    • Steps for obtaining a simple random sample for outcomes in trauma hospitals.

Page 27

  • Cluster Sampling

    • Dividing the population into clusters based on demographic parameters.

    • Random selection of clusters for effective survey results.

Systematic Sampling

  • Definition: Choosing sample members at regular intervals

  • Process: Selection of a starting point, sample size, and regular intervals

    • Example: Selecting every 10th individual from a population of 5000 to form a sample of 500

Stratified Random Sampling

  • Definition: Dividing the population into non-overlapping groups

  • Purpose: Representing the entire population accurately

    • Example: Creating strata based on annual income divisions for targeted analysis

Probability Sampling Advantages

  • Benefits:

    • Reduce sample bias

    • Ensure diverse population representation

    • Create an accurate sample for well-defined data collection

Non-Probability Sampling

  • Definition: Sample selection based on researcher's discretion

  • Usage: Preliminary research stages or cost constraints

    • Output may lead to skewed results in some cases

Convenience Sampling

  • Dependence: Ease of access to subjects

  • Example: Surveying customers at a mall or passers-by on a busy street

    • Commonly used in resource-limited situations like startups or NGOs

Judgmental or Purposive Sampling

  • Definition: Samples formed based on researcher's discretion

  • Criteria: Selection based on the purpose of the study and target audience understanding

Snowball Sampling

  • Usage: When subjects are difficult to trace

  • Example: Applied in sensitive topics like HIV/AIDS surveys

Quota Sampling

  • Selection: Based on pre-set standards

  • Purpose: Rapid method of collecting samples with specific attributes

Advantages of Non-Probability Sampling

  • Usage:

    • Create hypotheses with limited prior information

    • Conduct exploratory research or pilot studies

    • Address budget and time constraints for preliminary data collection

Differences between Probability and Non-Probability Sampling

  • Probability Sampling:

    • Randomly selected samples

    • Used to reduce sampling bias

  • Non-Probability Sampling:

    • Subjective judgement of researchers

    • Useful in specific environments with similar characteristics among