








Combinations
Glossary of Statistical Terms 
The number of combinations of n things taken k at a time is the number of ways of picking a subset of k of the n things, without replacement, and without regard to the order in which the elements of the subset are picked. the number of such combinations is nck = n!/(k!(n−k)!), where k! (pronounced "k factorial") is k×(k−1)×(k−2)× … × 1. the numbers nck are also called the binomial coefficients. from a set that has n elements one can form a total of 2n subsets of all sizes. for example, from the set {a, b, c}, which has 3 elements, one can form the 23 = 8 subsets {}, {a}, {b}, {c}, {a,b}, {a,c}, {b,c}, {a,b,c}. because the number of subsets with k elements one can form from a set with n elements is nck, and the total number of subsets of a set is the sum of the numbers of possible subsets of each size, it follows that nc0+nc1+nc2+ … +ncn = 2n. the calculator has a button (ncm) that lets you compute the number of combinations of m things chosen from a set of n things. to use the button, first type the value of n, then push the ncm button, then type the value of m, then press the "=" button.

Binomial coefficient, английский
 Combinations
 Биномиальный коэффициент
 The binomial coefficient counts the number of ways n items can be partitioned into two groups, one of size k and the other of size nk. it is computed as see also: binomial distribution, multinomial coefficient.

Replacement, английский
 Замена
 Замещение; возмещение; воспроизводство^
 An operation to replace part of the body with an artificial part
 N подстановка replacive a замещающий, подстановочный
 Construction of a new pipe or underground utility located on or off the line of the existing systems, which serves the same function as the old system.
Pronounced, английский
A заметный, явный (син. noticeable) accent

Mutually exclusive, английский
 Disjoint events or disjoint sets
 Взаимоисключающий
Binomial coefficient, английский
 Combinations
 Биномиальный коэффициент
 The binomial coefficient counts the number of ways n items can be partitioned into two groups, one of size k and the other of size nk. it is computed as see also: binomial distribution, multinomial coefficient.






