Key Science Skills (2024)

• a hypothesis is an educated guess
• The aim outlines the purpose of a study in a science investigation.
• An independent variable is the variable that is manipulated by the researcher to see how it affects the dependent variable
• Dependent Variable - The variable being measured or observed, which changes as a result of changing the independent variable.
• Controlled variables are factors that remain constant throughout the experiment.
• operationalized variable: a variable that has been made measurable and therefore can be used in research
• Participants are the individuals who are selected and tested for the research.
• A group of participants are called a sample. The sample is a subset of the population.
• There are three types of sampling: Convenience, Random, and Stratified.
• Convenience Sampling: Participants are chosen because they are easy to find.
• Random Sampling: A random selection process ensures all members have an equal chance of being included in the sample.
• Stratified Sampling: This type of sampling involves dividing the population into groups based on certain characteristics such as age, gender, ethnicity etc., then randomly selecting from these subgroups.
• Stratified Sampling: This type of sampling involves dividing the population into groups based on certain characteristics such as age or gender.
• The researcher must ensure that their results can be generalised to the whole population.
• Generalisation: When we make conclusions about a larger group based on information gathered from a smaller group.
• An extraneous variable is any variable other than the IV that can cause a change in the DV, and therefore affect the results of the experiment in an unwanted way.
• A confounding variable is when two variables are not controlled properly during an investigation so they cannot be distinguished from one another.
• Control Group: The group receiving no treatment or intervention in an experiment.
• Types of experimental designs: Between subjects, within-subjects, and mixed subject design.
• Between-Subjects Design: Each participant only takes part in one condition of the independent variable.
• Mixed Subjects Design: A combination of between-subjects and within-subjects design.
• Within-Subjects Design: Participants take part in all conditions of the independent variable.
• Conclusions are statements regarding the results of an investigation as to whether the hypothesis was supported or not.
• Generalisations are the extent to which the results of an investigation can be applied to the wider research population