Cours6

• Experimental studies


  Advanced data collection methods
• Two groups


  • G1 - uses VR treatment
  • G2 - uses traditional treatment
• VR could be used to treat psychological issues (e.g., smoking)


  Nicotine is highly addictive and cues to smoking increase cravings
• Common treatment


  Repeated exposure of pictures of stimuli related to smoking to elicit nicotine cravings where it is not fulfilled
• Theory


  States that over time the patient will lose the cravings (process called extinction). Traditional therapy has shown only limited effectiveness.
• Why traditional therapy has limited effectiveness

  Maybe pictures are not real enough. Can VR improve smoking reduction because it uses more realistic stimuli?
• Manipulation


  The researcher intervenes in the situation studied
• Measurement


  After manipulation, we need to see what happens. We measure the outcome of changing the IV.
• Control


  At least two different situations, one for each change in the IV. As the IV is changed, everything else in the experiment must remain the same.
• Lack of control on the confounding variables = lack of experimental power
• Internal validity


  Experiment designed properly so that a causal conclusion can be made. The confounding variables must be eliminated from the design.
• Internal validity - threats

  Variability between different people as well as within a single person
• Internal validity - how to avoid threats

  Random assignment = each participant has an equal probability of being in any condition of the experiment
• Random sampling != random assignment
• Field experiment


  An experiment conducted in the real world, outside of a controlled laboratory setting
• Field experiment


  • Deters and Mehl (2013) - were interested in the effects of making FB posts
• External validity


  How much do results from the laboratory have any meaning in the much less controlled real world
• Online research methods


  Research concerns that are unique to online research
• Online research concerns


  • Data fraud
  • Participant motivation
  • Multiple entries
  • Hardware and equipment variation
  • Online impressions
• As people age, they are more interested in controlling their online impressions
• Online research methods - advantages

  • Easy to recruit participants
  • Large number of participants
  • Useful in cross-cultural studies
• Ecological Momentary Assessment (EMA)


  Repeated sampling of subjects' current behaviors and experiences in real time, in subjects' natural environments. Aims to minimize recall bias, maximize ecological validity, and allow study of microprocesses that influence behavior in real-world contexts.
• Some questions explored with EMA

  • How much craving do smokers experience when they quit smoking?
  • Does craving intensity vary with individual characteristics, such as nicotine dependence?
  • Are day-to-day changes in craving intensity associated with variations in subsequent risk of smoking?
  • Does experiencing emotional distress predispose smokers to lapse?
  • Do situational factors affect lapse risk?
  • Do lapses diminish self-efficacy?
• Surprisingly little, except in discrete episodes (Shiffman et al., 1997)
• Yes (Shiffman et al., 2004.)
• Yes, especially craving experienced first thing in the morning (Shiffman et al., 1997)
• Yes, but only acute distress, over a period of hours; Shiffman & Waters, 2004)
• Yes, especially emotional distress, others smoking, and alcohol consumption; (Shiffman et al., 1996)
• Yes (Shiffman et al., 1997)
• Assessments in EMA


  Focus on subjects' current state; for example, self-reports ask about current feelings (or very recent ones), rather than asking for recall or summary over long periods. This is the "momentary" aspect of EMA and aims to avoid the error and bias associated with retrospection.
• Subjects complete multiple assessments over time, providing a picture of how their experiences and behavior varies over time and across situations.
• EMA software


  • https://www.expiwell.com/
  • https://jruwaard.github.io/aph_ema_handbook/ema-instruments-catalogue.html#ema-platforms-apps
  • Wearables
  • https://www.otago.ac.nz/cs/groups/public/@psychology/documents/webcontent/otago047475~3.pdf