Hypothesis and experimentation

The mean of repeated trials reduces random fluctuations. In exams averaging improves reliability but does not remove systematic error.

The independent variable is usually placed on the horizontal axis and the dependent variable on the vertical axis. In exams check axis labels and units.

When one variable increases while the other decreases the relationship is negative. In exams remember that correlation alone does not prove causation.

Controlled manipulation allows the effect of a cause to be isolated. In exams distinguish correlation from causation.

A representative and adequate sample makes generalization more reasonable. In exams consider sampling bias.

Leaf number may not accurately represent total biomass. In exams evaluate the validity of the chosen indicator.

A wide spread indicates uncertainty even when the means are equal. In exams examine distribution as well as the mean.

A small sample may be strongly affected by chance so the conclusion should be limited. In exams judge evidence strength partly by sample size.

An operational definition states exactly how a concept will be measured. In exams convert vague terms into measurable terms.

A task of equal difficulty ensures a fair comparison of performance. In exams keep supporting factors such as task and time constant.

Without a clear method other researchers cannot reproduce the experiment. In exams state quantities equipment and steps clearly.

Knowing the treatment may let expectations influence performance. In exams blinding reduces expectation bias.

Keeping mass and conditions equal while changing only surface area provides clear support. In exams look for a fair comparison.

When error exceeds the observed difference the claim of an effect is weak. In exams compare uncertainty with the size of the difference.

Calibration reduces systematic error and brings measurements closer to the true value. In exams distinguish accuracy from reliability.

The number of correctly recalled words is a measurable outcome of memory performance. In exams choose an outcome directly linked to the hypothesis.

Results from one condition cannot automatically be applied to all conditions. In exams limit conclusions to the tested range.

Peer review helps identify weaknesses and unsupported conclusions in scientific work. In exams treat it as a quality-check process.

Only two values cannot reveal the shape of a trend or intermediate changes. In exams use several values across a suitable range.

Preference-based grouping may create initial differences that affect the result. In exams random allocation reduces bias.

Scientific conclusions are worded cautiously according to the strength of evidence. In exams distinguish terms such as suggests and proves.

Actual temperature and repeated measurements verify both the variable and the outcome. In exams record the actual values of the independent variable.

Risk assessment reduces the chance of injury and damage. In exams match each hazard with an appropriate precaution.

Scientific investigations should protect organism welfare and minimize harm. In exams treat ethics as important as experimental validity.

Partial support suggests that the hypothesis should be refined with more precise conditions. In exams view science as a process that improves with evidence.