Exercise 1.
# Label columns x, F(x), DF(x), freq
SET ‘x’
-1000.5 89.5:189.5/20 1000.5
END
CDF ‘x’ ‘F(x)’;
NORMAL 131.5 20.
DIFFERENCES ‘F(x)’ ‘DF(x)’
LET ‘freq’ = ‘DF(x)’*100

Exercise 2.
# (i) Find expected relative frequencies for normal distribution, with mean 4.5 and s.d. 9.08, using class boundaries 10.5, 20.5, …, 90.5, as in previous question.
#Name C11, ‘sum’; C12, ‘interval’; C13, ‘interval list’; C14, ‘observed freq’.
RANDOM 500 C1-C10;
INTEGER 0 9.
RSUM C1-C10 ‘sum’
# (ii) Code values falling in chosen interval by centre of interval. All intervals must be listed.
CODE (0.5:10.5) 5.5 (10.5:20.5) 15.5 …(80.5:90.5) 85.5 ‘sum’ ‘interval’
TALLY ‘interval’;
STORE ‘interval list’ ‘observed freq’

Exercise 3.
# Label columns N, U, E.
RANDOM 160 ‘N’;
NORMAL 5 1.
RANDOM 160 ‘U’;
UNIFORM 2 8.
RANDOM 160 ‘E’;
EXPONENTIAL 5.
HISTOGRAM ‘N’;
TITLE “N160”.
HISTOGRAM ‘U’;
TITLE “U160”.
HISTOGRAM ‘E’;
TITLE “E160”.
# Use Editor>Layout Tool to compare the graphs.
DELETE 81:160 ‘N’ ‘U’ ‘E’
# and repeat.

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