Essay on Business Statistics

Submitted By bonnyhare
Words: 803
Pages: 4

**By all that confused you
1. Computer the mean, median, range, variance, standard deviation, quartiles, interquartile range and coefficient of variation for all numerical values. In your report provide a typical undergraduate student “profile” based on these results.

**2. Prepare a frequency table, a well-labeled histogram, and a boxplot for spending allowing for eight intervals. Are the data skewed, if so how? Interval width = rounded to 110 to allow for 8 intervals

The data has a rightward skew in both the histogram and boxplot (explain the boxplot later with the whiskers and all) due to the majority of students who participated in the survey spending $640 or less on their textbooks and supplies.
3. Determine a whether a relationship exists between some of the numerical values, GPA vs appending, age, and average expected salary.
GPA and Spending Correlation below zero but closer to 0 than negative 1

GPA and Age above zero but closer to zero than 1

GPA and Expected Salary strongest positive relationship. There is a relatively strong positive linear relationship between GPA and expected Salary

4. Prepare one scatterplot of the variables in #3 with the strongest relationship

There is a positive correlation between GPA and expected salary.
5. For the variables GPA, expected salary, and annual salary in 5 years construct a 95% confidence interval estimate of the population mean. µ  population mean
GPA Mean

Expected Salary Mean

Annual Salary in 5 Years
Confidence Interval Estimate for the Mean

Data
Sample Standard Deviation
18.56
Sample Mean
77.64
Sample Size
50
Confidence Level
95%

Intermediate Calculations
Standard Error of the Mean
2.624780372
Degrees of Freedom
49
t Value
2.0096
Interval Half Width
5.2747

Confidence Interval
Interval Lower Limit
72.37
Interval Upper Limit
82.91

6. There has been reports of upward increases in overall grade point average across the nation. If the national average was being reported as 3.0 determine at the 0.05 level of significance whether there is evidence that the population mean is different than 3.0 based on this sample.

7. It is reported that nationally women make up 58% of those enrolled in 4-year colleges. At the 0.05 level of significance is there evidence that the proportion of women attending this University is different than 58%?

**8. There is interest in whether gender has an impact on grade point average. At the 0.05 level of significance and assuming data is approximately normal, is there evidence of a difference in grade point average between males and females?
F Test
F Test for Differences in Two Variances

Data
Level of Significance
0.05
Larger-Variance Sample Sample Size
26
Sample Variance
0.1942
Smaller-Variance Sample Sample Size
24
Sample Variance
0.128343

Intermediate Calculations
F Test Statistic
1.5131
Population 1 Sample Degrees of Freedom
25
Population 2 Sample Degrees of Freedom
23

Two-Tail Test Upper Critical Value
2.2871
p-Value
0.3216
Do not reject the null hypothesis

Pooled-Variance t Test for the Difference Between Two Means
(assumes equal population variances)

Data
Hypothesized Difference
0
Level of Significance
0.05
Population 1 Sample Sample Size
23
Sample Mean
3.14
Sample Standard Deviation
0.36601
Population 2 Sample Sample Size
26
Sample Mean
3.103462
Sample Standard Deviation
0.440681

Intermediate Calculations
Population 1 Sample Degrees of Freedom
22
Population 2 Sample Degrees of Freedom
25
Total Degrees of Freedom
47
Pooled Variance
0.166004
Standard Error
0.1166
Difference in Sample Means
0.036538
t Test Statistic
0.3133

Two-Tail Test Lower Critical Value
-2.0117
Upper Critical Value
2.0117
p-Value
0.7554…