GIVE NOW about ocw help & faqs contact us
18.05 | Spring 2014 | Undergraduate

# Introduction to Probability and Statistics

### 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("<h3>Calculator</h3>"); writecalculator(“psetcheckcalcid”, “Calculate”); whr(kdivcol,kdivwid);

At this point you should have installed R and R studio. If not, you should do that now.

The first thing to do with R is to make sure you can start it and then we will do some simple calculations. Give your answers to at least 2 decimal places of accuracy. Go ahead and start R Studio. You should see a window with 4 panes. The command prompt (the >) is in the bottom left window.

//Problem 1 problemNumber++; wl(problemheader(problemNumber)); wl(kp); var s; var partName, problemName, buttonLabel, answerArray, correct; s = [“At the command prompt type the command”, kp, rcmdna(“2 + 3”), kp, “Hit return and enter the result here.”]; wl(s.join(’ ‘)); wl(kp); partName = problemNumber; problemName = “prob” + partName; buttonLabel = “Check problem " + partName; writeNumericBox(partName+“id”, 5, buttonLabel, 0.001, kuseCorrectVal); whr(kdivcol,kdivwid);

//Problem 2 problemNumber++; wl(problemheader(problemNumber)); wl(kp); var s; var partName, problemName, buttonLabel, answerArray, correct; s = [“Do the following computations using R.”, kbr, “(Enter your answers in the boxes.)”]; wl(s.join(’ ‘)); wl(kp); wl(rcmdna(“2*3”)); wl(kbr) partName = problemNumber + " (a)” problemName = “prob” + partName; buttonLabel = “Check problem " + partName; writeNumericBox(partName+“id”, 6, buttonLabel, 0.01, kuseCorrectVal); wl(kp) wl(rcmdna(“2^3”)); wl(kbr) partName = problemNumber + " (b)” problemName = “prob” + partName; buttonLabel = “Check problem " + partName; writeNumericBox(partName+“id”, 8, buttonLabel, 0.01, kuseCorrectVal); wl(kp) wl(rcmdna(“3.14^3.14”)); wl(kbr) partName = problemNumber + " (c)” problemName = “prob” + partName; buttonLabel = “Check problem " + partName; writeNumericBox(partName+“id”, 36.338, buttonLabel, 0.01, kuseCorrectVal); whr(kdivcol,kdivwid);

//Problem 3 problemNumber++; wl(problemheader(problemNumber)); var s; var partName, problemName, buttonLabel, answerArray, correct; s = [“Use R to do the following computation.”, kbr, “(Enter your answer to 2 decimal places in the box.)”]; wl(s.join(’ ‘)); wl(kp); wl(rcmdna(“100*mean(sin(30:87))”)); wl(kbr) partName = problemNumber problemName = “prob” + partName; buttonLabel = “Check problem " + partName; writeNumericBox(partName+“id”, -2.215, buttonLabel, 0.01, kuseCorrectVal); whr(kdivcol,kdivwid);

//Problem 4 problemNumber++; wl(problemheader(problemNumber)); var s; var partName, problemName, buttonLabel, answerArray, correct; s = [“Now we’ll do our first random simulation. Don’t worry if you”, “don’t fully understand the commands. We will explain them in”, “the first tutorial. “, kp, “In order to simulate counting the number of heads in 1000 tosses of”, “a fair coin give the following sequence of commands.”, kp, “(Hit return after each one).”]; wl(s.join(’ ‘)); wl(kp); wl(rcmdna(“x = rbinom(1000,1,.5)”)); wl(kbr) wl(rcmdna(“total = sum(x)”)); wl(kp); wl(“You can use the up arrow to go back and run the commands again. You should get a different total.”); wl(kp); wl(“Give the value of the total number of heads for one of your simulations.”); wl(kbr) partName = problemNumber problemName = “prob” + partName; buttonLabel = “Check problem " + partName; s = “Expect the answer will be between 450 and 550”; writeNumericBox(partName+“id”, 500, buttonLabel, 460, s); whr(kdivcol,kdivwid);

## Course Info

##### Instructors

- Dr. Jeremy Orloff
- Jonathan Bloom

##### Departments

- Mathematics

##### As Taught In

Spring 2014

##### Level

Undergraduate

##### Topics

- Mathematics
  - Discrete Mathematics
  - Probability and Statistics

##### Learning Resource Types

assignment_turned_in Problem Sets with Solutions
grading Exams with Solutions
notes Lecture Notes
co_present Instructor Insights
theaters Other Video

Browse Resources

# You are leaving MIT OpenCourseWare

Please be advised that external sites may have terms and conditions, including license rights, that differ from ours. MIT OCW is not responsible for any content on third party sites, nor does a link suggest an endorsement of those sites and/or their content.