In: Statistics and Probability
Suppose you have two strains of mice, S1 and S2. Strain S2 is genetically modified to metabolize a pharmacon P supposedly faster than S1. You conducted an experiment in a sample set of each strain, in which the pharmacon was injected and its concentration in blood was measured every 15min for 2h. Of course, age, gender, and weight was recorded for each animal. You want to statistically demonstrate that the metabolic rate of N is higher in S2 than S1. For simplicity, let us assume that the pharmacon is metabolized by a 0th order (linear) kinetic.
1. Describe a statistically correct and efficient approach for analyzing the data.
2. Which statistical model is suitable to address the question above? Explain how this model works and how results are interpreted.
3. A few animals die (e.g., due to toxic effects) during the experiment. How would you deal with this problem in the statistical analysis?
(Answer).
(a)Describe a statistically correct and efficient approach for analyzing the data
According to question suppose you have two strains of mice, S1 and S2. Strain S2 is genetically modified to metabolize a pharmacon P supposedly faster than S1.So we need to compare two groups of mice,and we need to demonstarate that the metabolic rate of N is higher in S2 than S1.
here we need demonstrate the hypothesis that,
H_0:The metabolic rate of N is not higher in S2 than S1
H_1:The metabolic rate of N is not higher in S2 than S1
2. Which statistical model is suitable to address the question above? Explain how this model works and how results are interpreted.
Here ,we are comparing the two groups,i.e S1&S2,In general for comparing two groups of means we use t-test for independent samples or independent samples t-test.
we will find the mean's of each group's concentration in blood,and we will find the test statistic t
i.e
here,
=Mean of first sample S1
= Mean of second sample S2
= pooled Standard deviation
=Sample size of S1
=Sample size of S2
=Standard deviation of first sample S1
=Standard deviation of second sampleS2
We will find the degrr's of freedom by formula
df = n1 + n2 – 2
Next, using any t-table (these tables are always on the internet) we can get the critical values (tc) for the two tailed test.
we will choose the alpha critical value for rejecting the null hypothesis,
Using the t table we will get the value with respect to the degrees of freedom,
according that value if our t-calculated value is less than t-table value ,we will accept the alternative hypothesis and we must reject null hypothesis.
A few animals die (e.g., due to toxic effects) during the experiment. How would you deal with this problem in the statistical analysis?
The margin of error is a statistic expressing the amount of random sampling error in a survey's results.A margin of error tells you how many percentage points your results will differ from the real population value. For example, a 95% confidence interval with a 4 percent margin of error means that your statistic will be within 4 percentage points of the real population value 95% of the time.
So using the margin of error we can deal with the error rate