Basic statistics

### Basic statistics

Apple

This demo includes basic statistical analysis of Nielsen Ratings for Favourite Syndicated Programs from 1992-93, including minimum, maximum, range, count, sum, mean, median, variance, standard deviation, standard error and one-tailed non-paired T test.

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```// Two-sample T-test (one-taied, non-paired)
stat.ttest_ext = function(a,b)
{
// Use unbiased estimator of the variance
var v_a = stat.variance(a,true), v_b = stat.variance(b,true),
n_a = stat.count(a), n_b = stat.count(b),
T = Math.abs((stat.mean(a) - stat.mean(b))/Math.sqrt(v_a/n_a + v_b/n_b)),
df = Math.pow(v_a/n_a + v_b/n_b,2) /
(Math.pow(v_a/n_a,2)/(n_a - 1) + Math.pow(v_b/n_b,2)/(n_b - 1));

return {p: tdist(T,df), T: T};
}

//Nielsen Ratings for Favorite Syndicated Programs from 1992-93
var women,men,teenager,children,all = [];
women = [11.8,9.9,7.1,6.5,8.4,6.4,4.9,4.1,6.3,5.1,5.6,4.8,4.4,4.2,4.1,4.4,3.7,4.3,3.3,2.5];
men = [8.0,6.9,9.2,8.2,3.4,5.0,4.7,4.5,4.5,4.2,4.0,4.7,4.1,4.2,3.2,3.1,4.9,2.7,4.6,4.0];
teenager = [3.3,3.0,6.4,5.8,2.7,2.1,4.6,6.8,1.7,2.3,1.8,3.1,3.4,4.0,4.6,5.8,3.4,3.4,2.1,5.2];
children = [3.4,2.3,5.1,4.8,1.7,1.9,5.8,4.7,1.6,1.8,1.6,2.9,3.8,3.4,7.4,4.3,3.2,2.2,2.2,5.6];
all = all.concat(women,men,teenager,children);

//Return the minimal rating by women
text("The minimum rating by women is " + stat.min (women));
await(5000);

//Return the maximal rating by men
text("The maximun rating by men is " + stat.max (women));
await(5000);

//Return the rating range by teenagers
text("The range of rating by teenagers is " + stat.range(teenager));
await(5000);

//Return the count of rating by children
text("The count of rating by children is " + stat.count(children));
await(5000);

//Return the sum of all ratings
text("The sum of all ratings is " + stat.sum(all).toFixed(2));
await(5000);

//Return the mean value of all ratings
text("The mean of all ratings is " + stat.mean(all).toFixed(2));
await(5000);

//Return the median value of all ratings
text("The median of all ratings is " + stat.median(all));
await(5000);

//Return the variance of all ratings
text("The variance of all ratings is " + stat.variance(all).toFixed(2));
await(5000);

//Return the standard deviation of all ratings
text("The standard deviation of all ratings is " + stat.stddev(all).toFixed(2));
await(5000);

//Return the standard error of all ratings
text("The standard error of all ratings is " + stat.stderr(all).toFixed(2));
await(5000);

//between subject t-test (one-taied, non-paired)
ttest = stat.ttest_ext(women,men);
text("The result of a between subject t-test (one-taied, non-paired) on ratings by women and men " + "t = " + ttest.T.toFixed(2) + " p = " + ttest.p.toFixed(3));
await(5000);
```

Data inspection is forthcoming!

In the mean time, authors may download their own data and make it available as an Excel file. Check out the 'Stimuli and Files' tab.