DigitalKitty,
One of the issues you have is that you have not given names to your keys. Instead, you have used a value as a key. This is why the output of Data::Dumper is confusing. Consider this alternative: 
#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my %data;
while (<DATA>) {
    chomp;
    my ($ln, $fn, $score) = split ' ';
    $data{$ln} = {fn => $fn, score => $score};
}
print Dumper(\%data);

# Show just last names
print "$_\n" for sort keys %data;

# Show name and score
for my $ln (sort keys %data) {
    my ($fn, $score) = @{$data{$ln}}{qw/fn score/};
    print "$ln\t$fn\t$score\n";
}

__DATA__
Lateur Bart 97
Pierce Jerrad 96
Unknown planetscape 101
Miller Katie 86

[download]

Cheers - L~R

In reply to Re: Deciphering the output from Data::Dumper by Limbic~Region
in thread Deciphering the output from Data::Dumper by DigitalKitty

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