Module 3.5 - 3.6: Research Strategies 

3.5: Cautions When Applying Data

• $**Survey Method:**$ A research technique that questions a sample of people to collect information about attributes & behaviors
  • Surveys allow researchers to collect large amounts of data (questions. interviews)
  • Efficient, but results in bias due to wording (aid to the needy vs. welfare)
• $**Social Desirability**$: Self-report responses that make their response look good to others, even though it goes against their true beliefs.
• $**Population**$: The group of people you are collecting information from
  • $**Random Sample**$: Randomly selected individuals to represent a group as a whole. (equal chance)
  • researchers use mathematical formulas to find adequate #’s
    • Random → larger selection
    • Not random → Makes ample bias; bad conclusions

3.6: Longitude & Cross-Sectional Studies

• These techniques are used to show how individuals change during their lifespan. (Developmental Psychologist)
• $**Longitudinal Studies:**$ Follows the same group of individuals over a long time
  • $**Lewis Terman** (psychologist)$
  • began a famous longitudinal study group of intelligent children in California
    • Studied them for 70 years
    • Learned that they had successful careers
    • Best way to do developmental research
  • Type of study is expensive & difficult to conduct (rare)
• $**Cross-Sectional Studies:**$ Compares people of different ages at one time
  • more efficient than longitudinal studies, but can still result in problems
  • Ex: Due to Era, Culture, etc…
    • older individuals could have less memory ability compared to younger individuals
    • this could also be caused due to their education system over time (computers)
• $**Confounding Variables**$: Any variable, other than the Independent variable, which could impact the Dependent Variable.
• Individual differences
  • age, health, ability, etc
  • Fix: random assignment
• Environmental conditions
  • Temperature, light, noise, etc
• Expectation Effect
  • Participant or researcher bias
  • Fix: blind or double-blind studies; placebo
• $**Data Analysis:**$ statistical analysis is used to determine if data supports the hypothesis
• $**Statistically Significant**$: the possibility of the difference between groups occurring by chance alone is no more than 5% (p
• $**Central Tendency**$: Tendency of a majority of the numbers in a set to occur near the middle
  • Measures:
  • $**Mean**$ - mathematical average
  • $**Median**$- Midpoint in distribution
  • $**Mode**$- most frequent score