Question Type 13: Determining the type of two sample t-test and calculating the according t-statistic Exercises

Blood pressure is measured on 16 patients at two visits. The mean difference (visit 2 – visit 1) is $-6$ mmHg with $s_d=8$. Identify the test and compute t.

Determine the t-test type and calculate the t-statistic for independent samples assuming equal variances: $n_1=18$, $n_2=18$, ar x_1=82, ar x_2=78, $s_1=7$, $s_2=7$.

A study measures the same 8 subjects before and after a treatment. The mean difference (after–before) is $2.5$ units with $s_d=1.2$. Identify the t-test and calculate the t-statistic.

Determine the appropriate t-test type and calculate the t-statistic for two independent samples assuming equal variances with $n_1=10$, $n_2=12$, ar x_1=5.2, ar x_2=4.7, $s_1=1.1$, $s_2=1.3$.

Determine the t-test type and calculate the t-statistic for independent samples assuming equal variances: $n_1=20$, $n_2=22$, ar x_1=15.3, ar x_2=13.8, $s_1=4.2$, $s_2=3.9$.

Identify the t-test and compute the t-statistic for two independent samples with unequal variances: $n_1=14$, $n_2=14$, ar x_1=200, ar x_2=190, $s_1=15$, $s_2=20$.

Identify the t-test type and compute the t-statistic for two independent samples with unequal variances: $n_1=15$, $n_2=12$, $\bar x_1=78.5$, $\bar x_2=74.2$, $s_1=8.4$, $s_2=9.1$.

Identify the t-test and compute the t-statistic for two independent samples with unequal variances: $n_1=8$, $n_2=10$, ar x_1=50.5, ar x_2=47.2, $s_1=2.5$, $s_2=3.1$.

Determine the type and t-statistic for two independent samples assuming equal variances: $n_1=25$, $n_2=30$, ar x_1=170, ar x_2=165, $s_1=6$, $s_2=5.5$.

Lifespan of two battery types are tested independently: $n_1=20$, $n_2=22$, ar x_1=1200 h, ar x_2=1150 h, $s_1=100$, $s_2=150$. Identify the t-test and compute t.

A drug trial measures cholesterol in 12 patients before and after treatment. The mean difference (before–after) is $5$ mg/dL with $s_d=3.5$. Identify the test and find the t-statistic.

Reaction times of 10 subjects are measured before and after training. The mean difference (after–before) is $-0.12$ s with $s_d=0.05$. Identify the test and compute t.