Limiting False Positives in Research

Example of a Non-Significant Result: Nutritional Supplement

Criticisms of Null Hypothesis Testing

In psychological research, a finding is typically considered 'statistically significant' if the probability that the observed difference occurred by random chance is:

According to the standard criteria in psychology research, a result with a 10% probability of occurring by random chance would be classified as statistically significant.

A team of researchers has completed four separate psychological studies. Match each study's calculated p-value to the correct interpretation of its statistical significance based on the standard 5% threshold.

A researcher is evaluating the strength of evidence provided by four separate studies. Arrange these findings in order from the highest level of confidence to the lowest level of confidence that the observed result represents a meaningful effect rather than random chance, based on the standard threshold for statistical significance in psychology.

Match each term related to the standard of statistical significance in psychology with its correct description according to the course definition.

In psychological research, what does it mean to conclude that a finding is 'statistically significant' at the standard $5\%$ level?

A researcher finds that a treatment group performed better than a control group, with a probability of 0.03 that the result was due to random chance. Since this meets the standard threshold for significance, the researcher concludes that the findings are _____ rather than a fluke.

A neuropsychologist compares reaction times between two groups and finds a difference. Statistical analysis shows there is a $4\%$ probability that this difference occurred by random chance. According to standard criteria in psychological research, this finding should be classified as statistically significant.

A psychologist conducting an experiment on learning techniques must analyze their data to determine if the difference in test scores between two groups is statistically significant. Arrange the steps of this analytical process in the correct logical and chronological order, starting with the baseline assumption and ending with the final research conclusion.

An educational psychologist peer-reviews a manuscript investigating a new study tool. The manuscript's authors found that students using the tool scored higher than those who did not, with a calculated probability of 0.058 (or 5.8%) that the difference was due to random chance. The authors conclude that their tool's benefits are statistically significant. When evaluating this claim against the standard threshold for statistical significance in psychological research, the peer reviewer should judge the authors' conclusion to be _______ (justified/unjustified).

In psychological research, what is the standard probability threshold for a finding to be considered 'statistically significant'?

If a researcher observes a difference between two groups that has a 2% probability of occurring by random chance, this finding would typically be considered statistically significant.

Match each research scenario or concept to its correct interpretation based on the rules of statistical significance.

A developmental psychologist compares two different studies on toddler behavior. Study X reports a seven percent probability that its group differences are due to random chance, while Study Y reports a three percent probability. To confidently conclude which study's results are meaningful and not a fluke, the psychologist determines that only Study Y's findings are statistically ____.

As a peer reviewer, you must evaluate the validity of three different research claims. Based on the psychological standard for statistical significance, rank these study outcomes from the one that provides the strongest justification for concluding the results are meaningful (1) to the one that provides the weakest justification and fails to meet the standard (3).

Based on the standard in psychological research, what does it mean to declare a finding 'statistically significant'?

Which of the following best explains why psychologists use the five percent threshold for statistical significance?

Dr. Chen conducts a study on memory recall and observes a difference between the treatment and control groups. Statistical analysis shows there is an eight percent probability that this difference occurred by random chance. Based on standard psychological research practices, Dr. Chen should conclude that her findings are statistically significant.

Analyze the following probabilities that an observed difference in a study occurred by random chance. Match each probability to the correct analytical conclusion based on the standard for statistical significance in psychology.

A student is evaluating a published paper that claims a new study technique dramatically improves test scores. The paper reports a six percent probability that the test score differences between groups occurred by random chance. The student correctly critiques the paper's conclusion, noting that it fails to meet the standard criterion because the probability must be ____ percent or less to be considered statistically significant.