In: Math
ath & Music (Raw Data, Software
Required):
There is a lot of interest in the relationship between studying
music and studying math. We will look at some sample data that
investigates this relationship. Below are the Math SAT scores from
8 students who studied music through high school and 11 students
who did not. Test the claim that students who study music in high
school have a higher average Math SAT score than those who do not.
Test this claim at the 0.05 significance level.
Studied Music | No Music | |
count | Math SAT Scores (x1) | Math SAT Scores (x2) |
1 | 516 | 480 |
2 | 571 | 535 |
3 | 589 | 553 |
4 | 588 | 537 |
5 | 521 | 480 |
6 | 564 | 513 |
7 | 531 | 495 |
8 | 597 | 556 |
9 | 554 | |
10 | 493 | |
11 | 557 |
Solution:-
State the hypotheses. The first step is to state the null hypothesis and an alternative hypothesis.
Null hypothesis: uMusic = uNo Music
Alternative hypothesis: uMusic > uNo
Music
Note that these hypotheses constitute a one-tailed test.
Formulate an analysis plan. For this analysis, the significance level is 0.05. Using sample data, we will conduct a two-sample t-test of the null hypothesis.
Analyze sample data. Using sample data, we compute the standard error (SE), degrees of freedom (DF), and the t statistic test statistic (t).
Studied music | No music | ||
Mean | 559.625 | Mean | 523 |
Standard Error | 11.51697 | Standard Error | 9.500239 |
Median | 567.5 | Median | 535 |
Mode | - | Mode | 480 |
Standard Deviation | 32.57491 | Standard Deviation | 31.50873 |
Sample Variance | 1061.125 | Sample Variance | 992.8 |
Kurtosis | -1.89149 | Kurtosis | -1.82542 |
Skewness | -0.34246 | Skewness | -0.28312 |
Range | 81 | Range | 77 |
Minimum | 516 | Minimum | 480 |
Maximum | 597 | Maximum | 557 |
Sum | 4477 | Sum | 5753 |
Count | 8 | Count | 11 |
SE = sqrt[(s12/n1) +
(s22/n2)]
SE = 14.9297
DF = 17
t = [ (x1 - x2) - d ] / SE
t = 2.45
where s1 is the standard deviation of sample 1, s2 is the standard deviation of sample 2, n1 is thesize of sample 1, n2 is the size of sample 2, x1 is the mean of sample 1, x2 is the mean of sample 2, d is the hypothesized difference between population means, and SE is the standard error.
The observed difference in sample means produced a t statistic of 2.45.
Therefore, the P-value in this analysis is 0.012.
Interpret results. Since the P-value (0.012) is less than the significance level (0.05), hence we have to reject the null hypothesis.
From the above test we have sufficient evidence in the favor of the claim that students who study music in high school have a higher average Math SAT score than those who do not.