Independent groups

• Independent groups is when participants are divided into groups. The number of groups is dependent on the number of conditions. Each group participates in one condition of the experiment e.g. group 1 = condition 1
• A strength of independent groups is that participants only take part in one condition so there will be no order effects. As a result, the participants performance will not worsen due to boredom or fatigue. As such, order effects will not impact the participants performance and affect the results so they'll be due to IV manipulation. Thus increasing the validity
• A strength of independent groups is that because participants only partake in one condition, they are less likely to realise the aim of the experiment. This would prevent demand characteristics as participants will have less opportunity to change their behaviour which will lead to more accurate data. Thus increasing the validity of findings and conclusions drawn as findings are more likely to be due to the manipulation of the IV
• A weakness of independent groups is that there are participant variables that affect results. This is because two different groups of people are being compared and one group may be better than the other at the task naturally. Therefore we cannot be confident that the results obtained are due to the manipulation of the IV as existing differences between participants may end up affecting results to decrease the validity
• A weakness of independent groups is that it is very time consuming as it requires double the participants to have the sample size if it was a repeated measures design. This is a practical weakness of the design as it will also require more funding to pay for this experiment. Thus decreasing its practicality.