4 simple intro to statistics questions (each question has additional questions)
ID: 2934065 • Letter: 4
Question
4 simple intro to statistics questions (each question has additional questions) to be answered using IBM SPSS. No graphs required. Questions are related to hypothesis testing and t tests.
Mat 550 Statistical Analysis with Computers
Statistics
You are conducting a study to explore the relationship between systolic blood pressure and smoking status in women aged 25 to 35.
Write an alternative hypothesis to reflect your belief.
Write a null hypothesis to oppose your alternative hypothesis.
If you conduct a statistical test and obtain a p-value (sig.) of 0.09 would you reject the null hypothesis?
If you obtained a p-value of 0.03 would you reject null?
It is hypothesized that the average first year college student weighs 140 lbs.Below are data of the weights of first year students in a well-known professor’s Elementary Statistics class.
135 119 106 135 180 108 128 160 143 175 170
195 185 182 150 175 190 180 195 220 235
Test the claim that first year college student weigh an average of 140 lbs.
State Ho and H1
Using alpha 0.05, compute the t statistic and p-value (sig.)
Conclusion? (reject or fail to reject null)
Your interpretation about the average weight of the population of first year college students.
Following are data for age and drug screening results for patients under age 25 in a trauma center.
Age: 2 3 5 7 8 15 15 18 19 19
20 20 20 21 22 22 28 23 25 25
DrugScreen: 0 0 0 0 0 1 1 0 0 0
0 1 1 1 0 0 1 0 0 0
Is there a difference in average age in those who test positive for drugs compared to those who test negative?
Conduct an Independent Samples t Test to answer the question.
Ho
H1
Can we assume equal variances? (look at Levene’s sig.)
What is the test statistic?
P-value?
Reject Ho
What was the average age of those who tested negative?
Average age of those who tested positive?
Which age group is more likely to test positive for drugs in the population of those under age 25?
Let us consider a simple example of what is often termed "pre/post" data or "pretest posttest" data. Suppose you wish to test the effect of Prozac on the well-being of depressed individuals, using a standardized "well-being scale" that sums Likert-type items to obtain a score that could range from 0 to 20. Higher scores indicate greater well-being (that is, Prozac is having a positive effect). While there are flaws in this design (e.g., lack of a control group) it will serve as an example of how to analyze such data.
The value that we are interested in is the change score, and we obtain it by taking the difference between time 2 and time one.
Moodpre: 3 0 6 7 4 8 2 1 4
Moodpost: 5 1 5 7 10 9 7 11 8
State null and alternative hypotheses
In SPSS:
I. Create the two variables
II. Enter the data
III. Conduct a Paired Samples t Test
T value? P-value?
Conclude test (reject or fail to reject null)
Interpretation? At the 5% level of significance, there is (or there is not) conclusive evidence that Prozac significantly ……?
Explanation / Answer
Solving question 1
Alternative hypothesis is that there exists a positive correlation between systolic blood pressure and smoking
Null hypothesis is that there is no correlation between systolic blood pressure and smoking
SInce p-value is greater than 0.05, we cannot reject the null.
Since p-value is less than 0.05, we can reject the null hypothesis.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.