Fall 2014: HS 851
Scientific Methods for Health Sciences: Applied Inference
Homework 1
- Due Fri, Sept 12, 2014
- Homeworks, projects and assignments
- Homework Submission Rules
- Homework Headers
- Problem 1: Suppose we have obtained the following
measurements. Calculate the corresponding
power, specificity and sensitivity.
Actual Condition Absent (Ho is true) Present (H1 is true) Test Result Negative(fail to reject Ho) 0.983 0.0025 Positive (reject Ho) 0.0085 0.0055 - Problem 2: Using R and SOCR, generate 100 random observations from uniform(-1,1), normal(0,1) and exponential(1) distributions. Then Use the SOCR QQ Data-Data Plot to compare the paired samples, i.e., for each distribution, plot the quantiles of the R-generated sample against the SOCR generated sample. What do you expect and what do you see? Explain.
- Problem 3: The Poisson distribution with parameter λ can be approximated with normal when λ is large. Suppose patients arrive at a hospital at a rate of 50 per day. Let’s assume that the process is a Poisson random variable with λ=50. Compute the probability that in the next day the number of patients that arrive at this hospital will be between 54 and 62. Use the SOCR Normal (N(μ=50,σ=7.071)) and Poisson (Poisson(λ=50))distribution calculators.
- Problem 4: Use the Vitamin K shots Neonate Infant Pain Score (NIPS) dataset and SOCR Charts to generate a box plot, a scatter plot, a line plot, a dot plot, a boxplot, a histogram plot and a pie chart for some of the variables (Immediate, 30_Sec_Later, 60_Sec_Later, 120_Sec_Later, Total_Cry_Time).
