The probability distribution is a mathematical function that describes the likelihood of certain outcomes of a random event. It defines the probability of each possible outcome of a random experiment, which can range from a single event to a series of events. The probability distribution assigns a probability to each possible outcome and the sum of all the probabilities should be equal to one.
@import url(‘https://fonts.googleapis.com/css?family=Droid+Serif|Raleway’);
h1 {
text-align: center;
font-size: 50px;
margin-bottom: 0px;
font-family: ‘Raleway’, serif;
}
p {
color: black;
margin-bottom: 15px;
margin-top: 15px;
font-family: ‘Raleway’, sans-serif;
}
#words {
padding-left: 30px;
color: black;
font-family: Raleway;
max-width: 550px;
margin: 25px auto;
line-height: 1.75;
}
#words_summary {
padding-left: 70px;
color: black;
font-family: Raleway;
max-width: 550px;
margin: 25px auto;
line-height: 1.75;
}
#words_text {
color: black;
font-family: Raleway;
max-width: 550px;
margin: 25px auto;
line-height: 1.75;
}
#words_text_area {
display:inline-block;
color: black;
font-family: Raleway;
max-width: 550px;
margin: 25px auto;
line-height: 1.75;
padding-left: 100px;
}
#calcTitle {
text-align: center;
font-size: 20px;
margin-bottom: 0px;
font-family: ‘Raleway’, serif;
}
#hr_top {
width: 30%;
margin-bottom: 0px;
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height: 2px;
color: black;
background-color: black;
}
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margin-top: 15px;
border: none;
height: 2px;
color: black;
background-color: black;
}
#words_table label, #words_table input {
display: inline-block;
vertical-align: baseline;
width: 350px;
}
#buttonCalc {
border: 1px solid;
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margin-top: 20px;
cursor: pointer;
outline: none;
background-color: white;
color: black;
font-family: ‘Work Sans’, sans-serif;
border: 1px solid grey;
/* Green */
}
#buttonCalc:hover {
background-color: #f6f6f6;
border: 1px solid black;
}
#words_table, #answer, #error_msg {
color: black;
font-family: Raleway;
max-width: 350px;
margin: 25px auto;
line-height: 1.75;
}
#summary_table {
color: black;
font-family: Raleway;
max-width: 550px;
margin: 25px auto;
line-height: 1.75;
padding-left: 20px;
}
.label_radio {
text-align: center;
}
td, tr, th {
border: 1px solid black;
}
table {
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}
td, th {
min-width: 50px;
height: 21px;
}
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text-align: center;
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svg:not(:root) {
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td input {
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This calculator automatically finds the mean, standard deviation, and variance for any probability distribution.
Simply fill in the cells below for up to 10 values, then click the “Calculate” button:
Note: The Probability column must add up to 1.
Outcome | Probability | Value |
---|---|---|
Outcome 1 | ||
Outcome 2 | ||
Outcome 3 | ||
Outcome 4 | ||
Outcome 5 | ||
Outcome 6 | ||
Outcome 7 | ||
Outcome 8 | ||
Outcome 9 | ||
Outcome 10 |
Mean (μ) = 1.4500
Standard Deviation (σ) = 0.9734
Variance (σ2) = 0.9475
Probabilities must add up to 1. They currently add up to 0.359
//show answer to start
var answer_display = document.getElementById(“answer”);
//hide error message to start
var error_msg_display = document.getElementById(“error_msg”);
error_msg_display.style.display = “none”;
function calc() {
//get input data
var p1 = document.getElementById(‘p1’).value;
var p2 = document.getElementById(‘p2’).value;
var p3 = document.getElementById(‘p3’).value;
var p4 = document.getElementById(‘p4’).value;
var p5 = document.getElementById(‘p5’).value;
var p6 = document.getElementById(‘p6’).value;
var p7 = document.getElementById(‘p7’).value;
var p8 = document.getElementById(‘p8’).value;
var p9 = document.getElementById(‘p9’).value;
var p10 = document.getElementById(‘p10’).value;
var f1 = document.getElementById(‘f1’).value;
var f2 = document.getElementById(‘f2’).value;
var f3 = document.getElementById(‘f3’).value;
var f4 = document.getElementById(‘f4’).value;
var f5 = document.getElementById(‘f5’).value;
var f6 = document.getElementById(‘f6’).value;
var f7 = document.getElementById(‘f7’).value;
var f8 = document.getElementById(‘f8’).value;
var f9 = document.getElementById(‘f9’).value;
var f10 = document.getElementById(‘f10’).value;
var p_group = [p1, p2, p3, p4, p5, p6, p7, p8, p9, p10];
var f_group = [f1, f2, f3, f4, f5, f6, f7, f8, f9, f10];
var p_sum = parseFloat(math.sum(p_group)).toFixed(5);
var n = math.sum(f_group);
//do calculations
if (p_sum == 1) {
answer_display.style.display = “block”;
error_msg_display.style.display = “none”;
var muSTUFF = [];
for (var i=0; i product+n, 0);
var varSTUFF = [];
for (var i=0; i product+n, 0) – (mu*mu);
var sd = math.sqrt(variance);
document.getElementById(‘mu’).innerHTML = mu.toFixed(4);
document.getElementById(‘variance’).innerHTML = variance.toFixed(4);
document.getElementById(‘sd’).innerHTML = sd.toFixed(4);
}
else {
answer_display.style.display = “none”;
error_msg_display.style.display = “block”;
document.getElementById(‘p_sum’).innerHTML = p_sum;
}
} //end massive calc function