documentclass[tikz,border=3.14mm]{standalone}
usepackage{pgfplots}

begin{filecontents}{example.dat}
71
54
55
54
98
76
93
95
86
88
68
68
50
61
79
79
73
57
56
57
97
80
91
94
85
88
45
58
78
81
74
60
57
58
95
81
end{filecontents}

begin{document}
    begin{tikzpicture}
        begin{axis}[ybar, ymin=0]

            addplot[fill=black,
            hist={
                bins=11
            }] table [y index=0] {example.dat};

        end{axis}
    end{tikzpicture}

end{document}

pgfplotstableread{example.dat}table
pgfplotstablegetrowsof{table}
pgfmathsetmacro{R}{pgfplotsretval-1}

pgfplotsinvokeforeach{0,...,R}{
   pgfplotstablegetelem{#1}{0}of{table}
   pgfmathsetmacro value {pgfplotsretval}
   % sum up all e^0.5(value-x)/sigma somhow
}