Replication - basics
_________________ involves repeating a research study as precisely as possible, using the same methodologies, procedures, materials, and conditions as the original study. The goal is to determine whether the same results can be consistently reproduced.
Direct replication
Sample Size
The number of participants or observations included in a study. A larger ________ ______ can improve the accuracy and generalizability of the study's results.
If the ____ _____ were much smaller, say only 20 participants (10 per group), the results would be less reliable because a small ____ _____ might not represent the broader population accurately.
sample size
The practice of manipulating data analysis or selectively reporting results to achieve a statistically significant p-value (usually < 0.05). This might include running multiple analyses, selectively excluding data points, or only reporting outcomes that reach statistical significance, ultimately increasing the risk of false positives.
p-hacking
What is the primary goal of a replication study?
Correct Answer: B) To confirm the reliability of the original findings.
Original Study: Investigated the effect of sleep deprivation on memory recall using a specific word list.
______________ Replication: Repeats the experiment using the same word list, sleep deprivation protocol, and participant criteria.
Direct
A measure of the strength or magnitude of the relationship between variables or the impact of an intervention. _______ _________ helps to understand the practical significance of the results.
Effect size
What type of randomization it is about?
Simple Randomization
The practice of creating or modifying hypotheses after analyzing the data to make the results appear more theoretically supported. ___________ can lead to misleading conclusions because it presents post hoc explanations as if they were predicted in advance.
HARKing (Hypothesizing After Results are Known)
Which type of replication tests the same hypothesis with different methods or samples?
Correct Answer: C) Conceptual replication
_________ Replication
Confirms Reliability: Establishes that the findings are consistent and not due to chance or specific circumstances.
Strengthens Evidence Base: Builds confidence in the results, supporting the development of theories.
Detects Errors: Helps identify potential mistakes or biases in the original study.
Scientific Integrity: Upholds the principle of reproducibility, a cornerstone of scientific research.
Direct
A statistical measure that indicates the probability of obtaining results at least as extreme as the ones observed, assuming the null hypothesis is true. A smaller ______-value (typically < 0.05) suggests that the results are statistically significant.
p-value
What type of randomization it is about?
Stratified Randomization
A sample size that is too small to accurately represent the population or detect meaningful effects. An ______ ______ _______ can lead to unreliable results and an increased risk of Type II errors (failing to detect an effect that actually exists).
Underestimated Sample Size
Which of the following is NOT a type of replication?
Correct Answer: D) Inverse replication
_____________ Replication
Different Methodologies: Employs alternative experimental designs, measurements, or manipulations.
Same Hypothesis: Focuses on verifying the theoretical concept rather than the specific results.
Generalizability Testing: Assesses whether findings are applicable across different contexts or populations.
Innovation: Introduces new approaches to test the same idea, enhancing the robustness of the theory.
Conceptual
If the new method group scored an average of 85 and the traditional group scored an average of 80, an _____ _____ calculation (like Cohen’s d) would quantify the difference in a way that shows how meaningful it is, beyond just the statistical significance.
effect size
What type of randomization it is about?
Cluster Randomization
The probability of correctly detecting a true effect in a study. ________ _____ _______, often resulting from a small sample size or weak effect size, increases the likelihood of missing true effects, thus leading to inconclusive or non-significant results.
Low Statistical Power
What is the replication crisis primarily concerned with?
Correct Answer: B) A significant number of scientific findings failing to be replicated
Original Study: Explored individualistic vs. collectivistic tendencies in one country.
______________ Replication: Replicates the study in multiple countries to examine cultural influences.
Systematic (replication with modification)
______ ________ is especially important when interpreting results for decision-making, as it clarifies whether a statistically significant finding is also substantial enough to be considered valuable in practice.
Effect size
Example: ____________
All the company's employees are listed in alphabetical order.
From the first 10 numbers, you randomly select a starting point: number 6.
From number 6 onward, you select every 10th person in the list (6, 16, 26, 36 and so on), and finally you get a sample of 100 people.
Systematic sampling
The absence of a random assignment process in an experiment or study, which can lead to biased groups and confounded results. Without __________, it's difficult to ensure that observed effects are due to the treatment rather than pre-existing differences between groups.
Lack of Randomization
Which of the following is a contributing factor to the replication crisis?
Correct Answer: B) Publishing only studies with significant results