chore: address commit comments

lib/node_modules/@stdlib/stats/base/dists/planck/stdev/README.md

@@ -64,7 +64,8 @@ v = stdev( 1.5 );
 // returns ~0.6080
 ```
 
-If provided a success probability `λ` which is nonpositive, the function returns `NaN`.
+If provided a shape parameter `λ` which is nonpositive, the function returns `NaN`.
+
 
 ```javascript
 var v = stdev( NaN );

lib/node_modules/@stdlib/stats/base/dists/planck/stdev/benchmark/benchmark.js

@@ -39,7 +39,7 @@ bench( pkg, function benchmark( b ) {
 	len = 100;
 	lambda = new Float64Array( len );
 	for ( i = 0; i < len; i++ ) {
-		lambda[ i ] = uniform( 1.0, 11.0 );
+		lambda[ i ] = uniform( 0.1, 11.0 );
 	}
 
 	b.tic();

lib/node_modules/@stdlib/stats/base/dists/planck/stdev/lib/native.js

@@ -30,7 +30,8 @@ var addon = require( './../src/addon.node' );
 *
 * @private
 * @param {number} lambda - shape parameter
-* @returns {Probability} evaluated standard deviation
+* @returns {PositiveNumber} standard deviation
+
 *
 * @example
 * var v = stdev( 0.1 );