Reading Questions Answer Checker
To check your answers put them in the appropriate box and click the ‘Check’ button. Every checker box can do arithmetic and calculate standard functions (see calculator help). If you give decimal answers, give them to at least 3 decimal places.
As you work you should have pencil and paper handy for calculations and thinking!
Note: some questions ask for a formula. For the checker we ask you to plug a value into the formula. For your pset you still need to give the whole formula.
//DEBUG PARAMETERS //Because we don’t show solutions for pset checkers we use //this to give a showanswer button during the debugging phase var debugans = undefined; //release //var debugans = kDebugAnswer; //debug problemNumber = 0; wl(“Calculator”); writecalculator(“psetcheckcalcid”, “Calculate”); whr(kdivcol,kdivwid);
//Problem 1 problemNumber++; wl(problemheader(problemNumber)); var s; var partName, problemName, buttonLabel, answerArray, correct; s = “True or False. A density histogram of 100000 values is always close to the graph of the underlying density.” wl(s); wl(kbr); partName = problemNumber + " (b)"; problemName = “prob” + partName; buttonLabel = “Check problem " + partName; correct = “False”; var answerArray = [“True”, correct]; writeMultipleChoiceRadioGroup(answerArray, problemName, correct, buttonLabel); wl(kp); whr(kdivcol,kdivwid);
//Problem 2 problemNumber++; wl(problemheader(problemNumber)); var s; var partName, problemName, buttonLabel, answerArray, correct; s = “If $X$ has mean $μ=2$ and variance $σ^2=4$ then which of the following is the standardization of $X$?"; wl(s); wl(kbr); partName = problemNumber + " (b)"; problemName = “prob” + partName; buttonLabel = “Check problem " + partName; correct = “$(X-2)\/2$”; var answerArray = [correct, “$(X-4)\/4$”,“$(X-2)\/4$”,“$(X-4)\/2$”]; writeMultipleChoiceRadioGroup(answerArray, problemName, correct, buttonLabel); wl(kp); whr(kdivcol,kdivwid);
//Problem 3 problemNumber++; wl(problemheader(problemNumber)); var s; var partName, problemName, buttonLabel, answerArray, correct; s = “If $Y$ is a standard normal random variable and $W = 3Y + 4$ then what is the mean of $W$?"; wl(s); wl(kp); partName = problemNumber; problemName = “prob” + partName; buttonLabel = “Check problem " + partName; writeNumericBox(partName+"id”, 4, buttonLabel, 0.001, kuseCorrectVal); wl(kp); whr(kdivcol,kdivwid);
//Problem 4 problemNumber++; wl(problemheader(problemNumber)); var s; var partName, problemName, buttonLabel, answerArray, correct; s = [“A fair coin is tossed 64 times. Use the central limit theorem to estimate the probability of getting more that 40 heads.", kp, “Hint: you can do this without R using a rule of thumb to help find the appropriate tail probability.", “For this problem you only have to be within 0.004 of the exact answer to get a green check."]; wl(s.join(’ ‘)); wl(kp); partName = problemNumber; problemName = “prob” + partName; buttonLabel = “Check problem " + partName; writeNumericBox(partName+"id”, .025, buttonLabel, 0.004, “Exact: 0.0227, rule-of-thumb: 0.025”); wl(kp); whr(kdivcol,kdivwid);