SPSS Assignment Part II (Links To An External Source)

SPSS Assignment Part II SPSS Assignment 2 (Links to an external site.) I

Perform four statistical tests using SPSS based on the described studies:

1. One Sample t Test: Test whether caffeine affects memory recall by comparing a sample of 30 subjects' recall scores to an known population mean of 6, using a one-sample t-test in SPSS.
2. Paired Samples t Test: Examine the effect of caffeine versus placebo on the same 30 subjects, using pre-test and post-test scores, with a paired-samples t-test in SPSS.
3. Independent Samples t Test: Compare recall scores between two groups (caffeine vs placebo) with 60 participants assigned randomly, using an independent samples t-test in SPSS.
4. One-Way ANOVA: Assess the effect of three different drugs (Placebo, Caffeine, Limitless) on memory recall with 90 participants divided into three groups, using a one-way ANOVA in SPSS.

Paper For Above instruction

This paper provides a comprehensive analysis of experimental procedures and statistical testing to evaluate the effects of various substances on memory recall, employing SPSS software for data analysis. The study encompasses four distinct tests: one-sample t-test, paired-samples t-test, independent-samples t-test, and one-way ANOVA, each tailored to different experimental designs and hypotheses regarding caffeine and novel drug effects on memory performance.

Introduction

Memory, a critical cognitive function, can be influenced by numerous pharmacological agents, including caffeine and emerging drugs such as "Limitless." Evaluating the impact of these substances necessitates rigorous statistical testing, often employing SPSS software. This research aims to investigate these effects through various experimental designs: comparing sample means to a known population mean, assessing within-subject changes, comparing independent groups, and analyzing differences across multiple groups using analysis of variance (ANOVA).

One Sample t-Test

The first analysis addresses whether caffeine intake enhances memory recall relative to a known population mean. Data from 30 subjects who took a caffeine pill and completed a memory test of 10 words is analyzed using a one-sample t-test. The known population mean recall score, derived from prior unstimulated participants, is 6. With SPSS, the data entry involves creating a variable named "CAFFEINE" and inputting scores for each participant. The t-test compares the sample mean against the population mean of 6, accounting for the unknown standard deviation by using the t-distribution.

Findings from the SPSS output indicate whether caffeine significantly improves memory recall, based on the t-value, degrees of freedom, and p-value. If the p-value is less than the alpha level of 0.05, the null hypothesis of no difference is rejected, suggesting caffeine has a statistically significant effect on memory performance.

Paired-Samples t-Test

The second analysis involves a within-subjects design with 30 participants subjected to both placebo and caffeine conditions in a pre-test/post-test format. Each participant's memory scores after consuming placebo and caffeine are recorded. Using SPSS, the variables "CAFFEINE" (post-test) and "PLACEBO" (pre-test) are entered, and a paired-samples t-test is conducted to determine whether the mean difference in scores is statistically significant.

The SPSS output provides t-value, degrees of freedom, and the significance level. A significant result indicates caffeine's effect on memory within the same set of subjects, controlling for individual differences. Effect size measures like Cohen's d can be calculated to interpret the practical significance of findings.

Independent Samples t-Test

The third analysis compares memory recall between two independent groups: one receiving caffeine and the other placebo, with 30 participants in each group. Data entry involves creating variables "SCORES" and "CAFFEINE," with "CAFFEINE" coded as 1 for caffeine and 2 for placebo, including labels for clarity. An independent-samples t-test in SPSS assesses whether there are significant differences in recall scores between these groups.

Results from SPSS include the t-value, degrees of freedom, and p-value, guiding whether caffeine impacts memory compared to placebo. Assumption checks such as homogeneity of variances (Levene's test) accompany the analysis.

One-Way ANOVA

The final analysis evaluates the effect of three different substances—Placebo, Caffeine, Limitless—on memory recall across 90 participants divided into three groups of 30. Data management in SPSS involves creating variables "SCORES" and "DRUGS," with "DRUGS" labeled accordingly. The one-way ANOVA tests whether mean recall differs significantly across the three drug conditions.

Post hoc analyses, such as Bonferroni tests, investigate specific group differences, controlling for familywise error. The ANOVA output includes F-statistic, significance level, and descriptive statistics, comprehensively illustrating the drug effects on memory.

Conclusion

Through these four analyses, the research rigorously tests the hypothesis that caffeine and a novel drug, Limitless, influence memory recall. The statistical procedures employed—t-tests and ANOVA—are standard in cognitive and behavioral research, enabling precise interpretation of experimental data. The results contribute to understanding pharmacological impacts on cognitive functions, with implications for future research and clinical applications.

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