WEBVTT Kind: captions Language: en 00:00:04.310 --> 00:00:07.519 align:start position:0% in<00:00:05.310> the<00:00:05.460> last<00:00:05.609> film<00:00:05.910> we<00:00:06.480> looked<00:00:06.690> at<00:00:06.839> variations 00:00:07.519 --> 00:00:07.529 align:start position:0% in the last film we looked at variations 00:00:07.529 --> 00:00:09.680 align:start position:0% in the last film we looked at variations in<00:00:07.710> people's<00:00:08.099> weight<00:00:08.400> and<00:00:08.730> discovered<00:00:09.570> that 00:00:09.680 --> 00:00:09.690 align:start position:0% in people's weight and discovered that 00:00:09.690 --> 00:00:11.780 align:start position:0% in people's weight and discovered that we<00:00:09.780> could<00:00:09.809> represent<00:00:10.230> a<00:00:10.710> whole<00:00:10.920> population<00:00:11.700> of 00:00:11.780 --> 00:00:11.790 align:start position:0% we could represent a whole population of 00:00:11.790 --> 00:00:14.870 align:start position:0% we could represent a whole population of people<00:00:11.969> by<00:00:12.570> a<00:00:12.599> normal<00:00:13.110> distribution<00:00:13.849> we<00:00:14.849> can 00:00:14.870 --> 00:00:14.880 align:start position:0% people by a normal distribution we can 00:00:14.880 --> 00:00:16.880 align:start position:0% people by a normal distribution we can explore<00:00:15.480> more<00:00:15.630> the<00:00:15.690> statistics<00:00:16.289> of<00:00:16.410> many 00:00:16.880 --> 00:00:16.890 align:start position:0% explore more the statistics of many 00:00:16.890 --> 00:00:20.210 align:start position:0% explore more the statistics of many phenomena<00:00:17.520> using<00:00:17.910> this<00:00:18.060> concept<00:00:19.010> if<00:00:20.010> we've 00:00:20.210 --> 00:00:20.220 align:start position:0% phenomena using this concept if we've 00:00:20.220 --> 00:00:22.040 align:start position:0% phenomena using this concept if we've measured<00:00:20.430> the<00:00:20.609> diameter<00:00:20.880> of<00:00:21.330> all<00:00:21.600> the<00:00:21.810> trees 00:00:22.040 --> 00:00:22.050 align:start position:0% measured the diameter of all the trees 00:00:22.050 --> 00:00:24.070 align:start position:0% measured the diameter of all the trees in<00:00:22.080> the<00:00:22.380> wood<00:00:22.560> and<00:00:22.800> then<00:00:23.100> plotted<00:00:23.760> that 00:00:24.070 --> 00:00:24.080 align:start position:0% in the wood and then plotted that 00:00:24.080 --> 00:00:26.349 align:start position:0% in the wood and then plotted that information<00:00:25.080> as<00:00:25.230> a<00:00:25.260> frequency<00:00:25.740> distribution 00:00:26.349 --> 00:00:26.359 align:start position:0% information as a frequency distribution 00:00:26.359 --> 00:00:30.109 align:start position:0% information as a frequency distribution what<00:00:27.359> would<00:00:27.480> it<00:00:27.570> look<00:00:27.689> like<00:00:28.429> it<00:00:29.429> would<00:00:29.640> conform 00:00:30.109 --> 00:00:30.119 align:start position:0% what would it look like it would conform 00:00:30.119 --> 00:00:32.450 align:start position:0% what would it look like it would conform to<00:00:30.480> something<00:00:30.960> like<00:00:31.140> a<00:00:31.199> normal<00:00:31.800> distribution 00:00:32.450 --> 00:00:32.460 align:start position:0% to something like a normal distribution 00:00:32.460 --> 00:00:36.260 align:start position:0% to something like a normal distribution you<00:00:32.730> have<00:00:33.480> a<00:00:33.600> few<00:00:33.899> very<00:00:34.079> small<00:00:34.200> trees<00:00:34.920> a<00:00:35.270> few 00:00:36.260 --> 00:00:36.270 align:start position:0% you have a few very small trees a few 00:00:36.270 --> 00:00:39.619 align:start position:0% you have a few very small trees a few very<00:00:36.690> large<00:00:37.140> ones<00:00:37.380> and<00:00:38.030> lots<00:00:39.030> and<00:00:39.270> lots<00:00:39.450> of 00:00:39.619 --> 00:00:39.629 align:start position:0% very large ones and lots and lots of 00:00:39.629 --> 00:00:39.979 align:start position:0% very large ones and lots and lots of them 00:00:39.979 --> 00:00:39.989 align:start position:0% them 00:00:39.989 --> 00:00:43.819 align:start position:0% them somewhere<00:00:40.950> in<00:00:41.040> between<00:00:42.290> we<00:00:43.290> can<00:00:43.469> use<00:00:43.649> these 00:00:43.819 --> 00:00:43.829 align:start position:0% somewhere in between we can use these 00:00:43.829 --> 00:00:45.830 align:start position:0% somewhere in between we can use these principles<00:00:44.070> to<00:00:44.670> consider<00:00:45.120> the<00:00:45.539> probability 00:00:45.830 --> 00:00:45.840 align:start position:0% principles to consider the probability 00:00:45.840 --> 00:00:50.029 align:start position:0% principles to consider the probability of<00:00:46.289> shares<00:00:46.710> making<00:00:47.219> a<00:00:47.340> given<00:00:47.610> return<00:00:48.860> the<00:00:49.860> way 00:00:50.029 --> 00:00:50.039 align:start position:0% of shares making a given return the way 00:00:50.039 --> 00:00:51.319 align:start position:0% of shares making a given return the way in<00:00:50.129> which<00:00:50.280> wealth<00:00:50.579> and<00:00:50.850> income<00:00:50.940> is 00:00:51.319 --> 00:00:51.329 align:start position:0% in which wealth and income is 00:00:51.329 --> 00:00:54.049 align:start position:0% in which wealth and income is distributed<00:00:52.129> order<00:00:53.129> likely<00:00:53.430> intelligence 00:00:54.049 --> 00:00:54.059 align:start position:0% distributed order likely intelligence 00:00:54.059 --> 00:00:55.910 align:start position:0% distributed order likely intelligence quotient<00:00:54.570> of<00:00:54.629> any<00:00:54.840> person<00:00:55.410> or<00:00:55.590> group<00:00:55.620> of 00:00:55.910 --> 00:00:55.920 align:start position:0% quotient of any person or group of 00:00:55.920 --> 00:00:59.720 align:start position:0% quotient of any person or group of people<00:00:56.600> the<00:00:57.600> list<00:00:57.840> is<00:00:57.989> endless<00:00:58.170> the<00:00:58.730> normal 00:00:59.720 --> 00:00:59.730 align:start position:0% people the list is endless the normal 00:00:59.730 --> 00:01:01.670 align:start position:0% people the list is endless the normal distribution<00:01:00.359> is<00:01:00.840> one<00:01:01.289> of<00:01:01.410> the<00:01:01.500> most 00:01:01.670 --> 00:01:01.680 align:start position:0% distribution is one of the most 00:01:01.680 --> 00:01:06.850 align:start position:0% distribution is one of the most important<00:01:02.309> concepts<00:01:02.730> and<00:01:02.940> statistics 00:01:06.850 --> 00:01:06.860 align:start position:0% 00:01:06.860 --> 00:01:09.800 align:start position:0% shoplifting<00:01:07.860> is<00:01:08.369> a<00:01:08.430> problem<00:01:09.030> for<00:01:09.210> retailers 00:01:09.800 --> 00:01:09.810 align:start position:0% shoplifting is a problem for retailers 00:01:09.810 --> 00:01:13.340 align:start position:0% shoplifting is a problem for retailers everywhere<00:01:10.590> but<00:01:11.369> the<00:01:11.490> problem<00:01:11.909> is<00:01:12.360> not<00:01:12.900> taking 00:01:13.340 --> 00:01:13.350 align:start position:0% everywhere but the problem is not taking 00:01:13.350 --> 00:01:16.609 align:start position:0% everywhere but the problem is not taking one<00:01:13.590> once<00:01:14.010> one<00:01:14.549> pieces<00:01:15.000> a<00:01:15.150> one<00:01:16.080> piece<00:01:16.380> of 00:01:16.609 --> 00:01:16.619 align:start position:0% one once one pieces a one piece of 00:01:16.619 --> 00:01:18.590 align:start position:0% one once one pieces a one piece of merchandise<00:01:17.009> apparently<00:01:17.909> taking<00:01:18.270> the<00:01:18.390> whole 00:01:18.590 --> 00:01:18.600 align:start position:0% merchandise apparently taking the whole 00:01:18.600 --> 00:01:21.530 align:start position:0% merchandise apparently taking the whole stack<00:01:19.049> and<00:01:19.350> running<00:01:19.680> that's<00:01:19.890> all<00:01:20.420> you<00:01:21.420> know 00:01:21.530 --> 00:01:21.540 align:start position:0% stack and running that's all you know 00:01:21.540 --> 00:01:25.249 align:start position:0% stack and running that's all you know they<00:01:21.720> comment<00:01:23.000> every<00:01:24.000> retailer<00:01:24.720> suffers<00:01:25.110> from 00:01:25.249 --> 00:01:25.259 align:start position:0% they comment every retailer suffers from 00:01:25.259 --> 00:01:27.920 align:start position:0% they comment every retailer suffers from it<00:01:25.759> what's<00:01:26.759> often<00:01:26.970> happened<00:01:27.390> with<00:01:27.540> I<00:01:27.720> mean 00:01:27.920 --> 00:01:27.930 align:start position:0% it what's often happened with I mean 00:01:27.930 --> 00:01:29.780 align:start position:0% it what's often happened with I mean thieves<00:01:28.170> nowadays<00:01:28.619> is<00:01:28.860> you<00:01:29.009> steal<00:01:29.250> to<00:01:29.430> order 00:01:29.780 --> 00:01:29.790 align:start position:0% thieves nowadays is you steal to order 00:01:29.790 --> 00:01:31.670 align:start position:0% thieves nowadays is you steal to order and<00:01:29.939> you<00:01:30.420> will<00:01:30.570> find<00:01:30.810> that<00:01:30.990> you<00:01:31.110> lose<00:01:31.350> a<00:01:31.380> lot<00:01:31.650> of 00:01:31.670 --> 00:01:31.680 align:start position:0% and you will find that you lose a lot of 00:01:31.680 --> 00:01:33.890 align:start position:0% and you will find that you lose a lot of books<00:01:32.009> say<00:01:32.250> you<00:01:32.670> would<00:01:32.820> spot<00:01:33.090> that<00:01:33.390> and 00:01:33.890 --> 00:01:33.900 align:start position:0% books say you would spot that and 00:01:33.900 --> 00:01:35.300 align:start position:0% books say you would spot that and because<00:01:34.200> we<00:01:34.350> know<00:01:34.530> what<00:01:34.740> should<00:01:34.890> be<00:01:35.040> on<00:01:35.159> our 00:01:35.300 --> 00:01:35.310 align:start position:0% because we know what should be on our 00:01:35.310 --> 00:01:38.960 align:start position:0% because we know what should be on our shelves<00:01:36.799> news<00:01:37.799> agents<00:01:38.250> also<00:01:38.579> suffer<00:01:38.939> from 00:01:38.960 --> 00:01:38.970 align:start position:0% shelves news agents also suffer from 00:01:38.970 --> 00:01:41.359 align:start position:0% shelves news agents also suffer from shoplifting<00:01:39.360> people<00:01:40.350> come<00:01:40.590> in<00:01:40.770> steal 00:01:41.359 --> 00:01:41.369 align:start position:0% shoplifting people come in steal 00:01:41.369 --> 00:01:45.350 align:start position:0% shoplifting people come in steal magazines<00:01:42.020> newspapers<00:01:43.020> etc<00:01:44.090> how<00:01:45.090> do<00:01:45.149> they 00:01:45.350 --> 00:01:45.360 align:start position:0% magazines newspapers etc how do they 00:01:45.360 --> 00:01:48.440 align:start position:0% magazines newspapers etc how do they control<00:01:45.750> it<00:01:46.520> at<00:01:47.520> one<00:01:47.700> thing<00:01:47.820> they<00:01:47.970> can<00:01:48.119> do<00:01:48.270> is 00:01:48.440 --> 00:01:48.450 align:start position:0% control it at one thing they can do is 00:01:48.450 --> 00:01:50.649 align:start position:0% control it at one thing they can do is install<00:01:49.020> security<00:01:49.619> devices<00:01:49.950> like<00:01:50.310> this<00:01:50.490> one 00:01:50.649 --> 00:01:50.659 align:start position:0% install security devices like this one 00:01:50.659 --> 00:01:53.990 align:start position:0% install security devices like this one but<00:01:51.659> it<00:01:51.750> costs<00:01:52.340> and<00:01:53.340> so<00:01:53.490> whatever<00:01:53.670> they<00:01:53.939> do 00:01:53.990 --> 00:01:54.000 align:start position:0% but it costs and so whatever they do 00:01:54.000 --> 00:01:56.319 align:start position:0% but it costs and so whatever they do it's<00:01:54.600> going<00:01:54.750> to<00:01:54.810> reduce<00:01:55.020> their<00:01:55.380> profits 00:01:56.319 --> 00:01:56.329 align:start position:0% it's going to reduce their profits 00:01:56.329 --> 00:01:58.609 align:start position:0% it's going to reduce their profits preventing<00:01:57.329> a<00:01:57.420> discouraging<00:01:58.049> theft<00:01:58.409> is 00:01:58.609 --> 00:01:58.619 align:start position:0% preventing a discouraging theft is 00:01:58.619 --> 00:02:01.520 align:start position:0% preventing a discouraging theft is costly<00:01:59.479> businesses<00:02:00.479> respond<00:02:00.930> to<00:02:01.020> shoplifting 00:02:01.520 --> 00:02:01.530 align:start position:0% costly businesses respond to shoplifting 00:02:01.530 --> 00:02:04.459 align:start position:0% costly businesses respond to shoplifting in<00:02:01.680> many<00:02:01.890> ways<00:02:02.159> with<00:02:02.549> security<00:02:03.479> systems<00:02:03.869> with 00:02:04.459 --> 00:02:04.469 align:start position:0% in many ways with security systems with 00:02:04.469 --> 00:02:07.370 align:start position:0% in many ways with security systems with item<00:02:04.979> tags<00:02:05.280> and<00:02:05.610> with<00:02:06.299> trained<00:02:06.719> staff<00:02:07.079> and 00:02:07.370 --> 00:02:07.380 align:start position:0% item tags and with trained staff and 00:02:07.380 --> 00:02:08.520 align:start position:0% item tags and with trained staff and surveillance 00:02:08.520 --> 00:02:08.530 align:start position:0% surveillance 00:02:08.530 --> 00:02:11.190 align:start position:0% surveillance even<00:02:09.220> University<00:02:09.850> Libraries<00:02:10.390> lose<00:02:10.660> books<00:02:10.990> to 00:02:11.190 --> 00:02:11.200 align:start position:0% even University Libraries lose books to 00:02:11.200 --> 00:02:11.840 align:start position:0% even University Libraries lose books to thieves 00:02:11.840 --> 00:02:11.850 align:start position:0% thieves 00:02:11.850 --> 00:02:14.970 align:start position:0% thieves in<00:02:12.850> response<00:02:13.390> this<00:02:14.020> library<00:02:14.290> has<00:02:14.590> installed 00:02:14.970 --> 00:02:14.980 align:start position:0% in response this library has installed 00:02:14.980 --> 00:02:17.460 align:start position:0% in response this library has installed electronic<00:02:15.790> item<00:02:16.120> tanks<00:02:16.540> and<00:02:16.690> electronic 00:02:17.460 --> 00:02:17.470 align:start position:0% electronic item tanks and electronic 00:02:17.470 --> 00:02:21.150 align:start position:0% electronic item tanks and electronic gates<00:02:18.660> most<00:02:19.660> businesses<00:02:20.200> simply<00:02:20.470> accept<00:02:21.010> that 00:02:21.150 --> 00:02:21.160 align:start position:0% gates most businesses simply accept that 00:02:21.160 --> 00:02:23.220 align:start position:0% gates most businesses simply accept that some<00:02:21.430> theft<00:02:21.670> is<00:02:21.850> going<00:02:22.060> to<00:02:22.150> take<00:02:22.330> place<00:02:22.510> and 00:02:23.220 --> 00:02:23.230 align:start position:0% some theft is going to take place and 00:02:23.230 --> 00:02:24.930 align:start position:0% some theft is going to take place and include<00:02:23.590> such<00:02:23.800> losses<00:02:24.250> in<00:02:24.430> their<00:02:24.550> business 00:02:24.930 --> 00:02:24.940 align:start position:0% include such losses in their business 00:02:24.940 --> 00:02:27.830 align:start position:0% include such losses in their business calculations<00:02:25.800> these<00:02:26.800> self-service<00:02:27.520> things 00:02:27.830 --> 00:02:27.840 align:start position:0% calculations these self-service things 00:02:27.840 --> 00:02:30.330 align:start position:0% calculations these self-service things saves<00:02:28.840> the<00:02:28.990> shop<00:02:29.200> quite<00:02:29.470> a<00:02:29.500> lot<00:02:29.680> of<00:02:29.709> money<00:02:29.920> it 00:02:30.330 --> 00:02:30.340 align:start position:0% saves the shop quite a lot of money it 00:02:30.340 --> 00:02:33.000 align:start position:0% saves the shop quite a lot of money it saves<00:02:30.700> them<00:02:30.910> on<00:02:31.030> library<00:02:31.390> costs<00:02:31.810> the<00:02:32.680> trouble 00:02:33.000 --> 00:02:33.010 align:start position:0% saves them on library costs the trouble 00:02:33.010 --> 00:02:35.010 align:start position:0% saves them on library costs the trouble is<00:02:33.160> it<00:02:33.760> also<00:02:34.030> makes<00:02:34.240> it<00:02:34.360> much<00:02:34.510> easier<00:02:34.780> for 00:02:35.010 --> 00:02:35.020 align:start position:0% is it also makes it much easier for 00:02:35.020 --> 00:02:38.310 align:start position:0% is it also makes it much easier for people<00:02:35.230> to<00:02:35.470> shoplift<00:02:36.660> so<00:02:37.660> why<00:02:37.840> do<00:02:37.900> they<00:02:38.110> have 00:02:38.310 --> 00:02:38.320 align:start position:0% people to shoplift so why do they have 00:02:38.320 --> 00:02:43.140 align:start position:0% people to shoplift so why do they have these<00:02:38.500> things<00:02:38.860> here<00:02:41.130> because<00:02:42.130> the<00:02:42.340> savings<00:02:42.940> on 00:02:43.140 --> 00:02:43.150 align:start position:0% these things here because the savings on 00:02:43.150 --> 00:02:45.449 align:start position:0% these things here because the savings on the<00:02:43.300> labor<00:02:43.510> costs<00:02:44.140> are<00:02:44.260> greater<00:02:44.680> than<00:02:45.130> the 00:02:45.449 --> 00:02:45.459 align:start position:0% the labor costs are greater than the 00:02:45.459 --> 00:02:47.270 align:start position:0% the labor costs are greater than the losses<00:02:45.820> on<00:02:45.970> the<00:02:46.060> shoplifting<00:02:46.660> shoplifting 00:02:47.270 --> 00:02:47.280 align:start position:0% losses on the shoplifting shoplifting 00:02:47.280 --> 00:02:49.770 align:start position:0% losses on the shoplifting shoplifting adds<00:02:48.280> to<00:02:48.520> the<00:02:48.610> cost<00:02:48.880> of<00:02:49.060> running<00:02:49.209> a<00:02:49.420> retail 00:02:49.770 --> 00:02:49.780 align:start position:0% adds to the cost of running a retail 00:02:49.780 --> 00:02:52.610 align:start position:0% adds to the cost of running a retail business<00:02:50.250> this<00:02:51.250> cost<00:02:51.550> is<00:02:51.730> estimated<00:02:52.360> at<00:02:52.480> about 00:02:52.610 --> 00:02:52.620 align:start position:0% business this cost is estimated at about 00:02:52.620 --> 00:02:55.350 align:start position:0% business this cost is estimated at about 1/3<00:02:53.620> of<00:02:53.890> 1%<00:02:54.130> of<00:02:54.700> sales 00:02:55.350 --> 00:02:55.360 align:start position:0% 1/3 of 1% of sales 00:02:55.360 --> 00:02:58.110 align:start position:0% 1/3 of 1% of sales it<00:02:55.989> doesn't<00:02:56.350> sound<00:02:56.590> much<00:02:56.770> but<00:02:57.430> it<00:02:57.550> has<00:02:57.700> around 00:02:58.110 --> 00:02:58.120 align:start position:0% it doesn't sound much but it has around 00:02:58.120 --> 00:03:00.060 align:start position:0% it doesn't sound much but it has around a<00:02:58.239> hundred<00:02:58.390> of<00:02:58.690> thirty<00:02:58.900> pounds<00:02:59.560> to<00:03:00.040> the 00:03:00.060 --> 00:03:00.070 align:start position:0% a hundred of thirty pounds to the 00:03:00.070 --> 00:03:03.560 align:start position:0% a hundred of thirty pounds to the average<00:03:00.520> family's<00:03:01.000> annual<00:03:01.270> shopping<00:03:01.989> bill 00:03:03.560 --> 00:03:03.570 align:start position:0% average family's annual shopping bill 00:03:03.570 --> 00:03:06.960 align:start position:0% average family's annual shopping bill how<00:03:04.570> big<00:03:04.750> a<00:03:04.840> problem<00:03:05.170> is<00:03:05.890> shoplifting<00:03:06.580> for<00:03:06.880> the 00:03:06.960 --> 00:03:06.970 align:start position:0% how big a problem is shoplifting for the 00:03:06.970 --> 00:03:10.020 align:start position:0% how big a problem is shoplifting for the individual<00:03:07.510> store<00:03:07.870> it<00:03:08.860> varies<00:03:09.430> from<00:03:09.640> store<00:03:10.000> to 00:03:10.020 --> 00:03:10.030 align:start position:0% individual store it varies from store to 00:03:10.030 --> 00:03:14.759 align:start position:0% individual store it varies from store to store<00:03:10.680> it<00:03:11.680> varies<00:03:12.160> from<00:03:12.400> day<00:03:12.700> to<00:03:12.760> day<00:03:13.590> but<00:03:14.590> the 00:03:14.759 --> 00:03:14.769 align:start position:0% store it varies from day to day but the 00:03:14.769 --> 00:03:16.890 align:start position:0% store it varies from day to day but the pattern<00:03:15.250> conforms<00:03:16.209> to<00:03:16.299> a<00:03:16.420> normal 00:03:16.890 --> 00:03:16.900 align:start position:0% pattern conforms to a normal 00:03:16.900 --> 00:03:19.410 align:start position:0% pattern conforms to a normal distribution<00:03:17.670> and<00:03:18.670> that<00:03:18.850> means<00:03:19.060> that<00:03:19.269> we 00:03:19.410 --> 00:03:19.420 align:start position:0% distribution and that means that we 00:03:19.420 --> 00:03:22.860 align:start position:0% distribution and that means that we could<00:03:19.630> say<00:03:19.840> quite<00:03:20.260> a<00:03:20.290> lot<00:03:21.000> because<00:03:22.000> we<00:03:22.330> can<00:03:22.510> use 00:03:22.860 --> 00:03:22.870 align:start position:0% could say quite a lot because we can use 00:03:22.870 --> 00:03:25.199 align:start position:0% could say quite a lot because we can use our<00:03:23.110> normal<00:03:23.560> distribution<00:03:23.890> to<00:03:24.730> examine<00:03:25.150> a 00:03:25.199 --> 00:03:25.209 align:start position:0% our normal distribution to examine a 00:03:25.209 --> 00:03:27.810 align:start position:0% our normal distribution to examine a whole<00:03:25.450> range<00:03:25.810> of<00:03:26.080> problems<00:03:26.620> about<00:03:27.220> the<00:03:27.459> size 00:03:27.810 --> 00:03:27.820 align:start position:0% whole range of problems about the size 00:03:27.820 --> 00:03:30.810 align:start position:0% whole range of problems about the size of<00:03:28.120> the<00:03:28.239> loss<00:03:29.100> but<00:03:30.100> if<00:03:30.220> we're<00:03:30.340> going<00:03:30.489> to<00:03:30.610> do 00:03:30.810 --> 00:03:30.820 align:start position:0% of the loss but if we're going to do 00:03:30.820 --> 00:03:33.810 align:start position:0% of the loss but if we're going to do that<00:03:31.030> we<00:03:31.870> first<00:03:32.170> have<00:03:32.440> to<00:03:32.590> transform<00:03:33.459> the 00:03:33.810 --> 00:03:33.820 align:start position:0% that we first have to transform the 00:03:33.820 --> 00:03:36.570 align:start position:0% that we first have to transform the normal<00:03:34.390> distribution<00:03:35.049> into<00:03:35.560> the<00:03:35.890> standard 00:03:36.570 --> 00:03:36.580 align:start position:0% normal distribution into the standard 00:03:36.580 --> 00:03:39.600 align:start position:0% normal distribution into the standard normal<00:03:36.820> distribution<00:03:38.010> let's<00:03:39.010> see<00:03:39.190> how<00:03:39.310> we<00:03:39.370> do 00:03:39.600 --> 00:03:39.610 align:start position:0% normal distribution let's see how we do 00:03:39.610 --> 00:03:42.660 align:start position:0% normal distribution let's see how we do that<00:03:40.739> the<00:03:41.739> standard<00:03:42.190> normal<00:03:42.220> distribution 00:03:42.660 --> 00:03:42.670 align:start position:0% that the standard normal distribution 00:03:42.670 --> 00:03:45.539 align:start position:0% that the standard normal distribution has<00:03:43.329> a<00:03:43.360> mean<00:03:43.480> of<00:03:43.720> 0<00:03:44.170> and<00:03:44.260> a<00:03:45.100> standard<00:03:45.130> deviation 00:03:45.539 --> 00:03:45.549 align:start position:0% has a mean of 0 and a standard deviation 00:03:45.549 --> 00:03:48.870 align:start position:0% has a mean of 0 and a standard deviation equal<00:03:46.450> to<00:03:46.540> 1<00:03:46.780> we<00:03:47.590> can<00:03:47.709> look<00:03:48.040> at<00:03:48.190> the<00:03:48.280> area<00:03:48.700> under 00:03:48.870 --> 00:03:48.880 align:start position:0% equal to 1 we can look at the area under 00:03:48.880 --> 00:03:51.600 align:start position:0% equal to 1 we can look at the area under the<00:03:49.209> curve<00:03:49.239> by<00:03:50.170> converting<00:03:50.680> into<00:03:51.220> what<00:03:51.489> are 00:03:51.600 --> 00:03:51.610 align:start position:0% the curve by converting into what are 00:03:51.610 --> 00:03:55.259 align:start position:0% the curve by converting into what are called<00:03:51.870> z-scores<00:03:52.870> an<00:03:53.519> any<00:03:54.519> normal 00:03:55.259 --> 00:03:55.269 align:start position:0% called z-scores an any normal 00:03:55.269 --> 00:03:58.140 align:start position:0% called z-scores an any normal distribution<00:03:55.500> can<00:03:56.500> be<00:03:56.530> converted<00:03:57.060> using<00:03:58.060> the 00:03:58.140 --> 00:03:58.150 align:start position:0% distribution can be converted using the 00:03:58.150 --> 00:04:02.660 align:start position:0% distribution can be converted using the transformation<00:03:58.959> that<00:03:59.200> Z<00:04:00.100> equals<00:04:00.750> X<00:04:01.750> minus<00:04:01.989> mu 00:04:02.660 --> 00:04:02.670 align:start position:0% transformation that Z equals X minus mu 00:04:02.670 --> 00:04:05.980 align:start position:0% transformation that Z equals X minus mu divided<00:04:03.670> by<00:04:03.820> Sigma 00:04:05.980 --> 00:04:05.990 align:start position:0% 00:04:05.990 --> 00:04:09.040 align:start position:0% where<00:04:06.380> X<00:04:06.860> is<00:04:07.370> the<00:04:07.670> score<00:04:08.180> of<00:04:08.360> the<00:04:08.480> original 00:04:09.040 --> 00:04:09.050 align:start position:0% where X is the score of the original 00:04:09.050 --> 00:04:12.970 align:start position:0% where X is the score of the original normal<00:04:09.410> distribution<00:04:10.180> mu<00:04:11.180> is<00:04:11.480> the<00:04:12.110> mean<00:04:12.590> of 00:04:12.970 --> 00:04:12.980 align:start position:0% normal distribution mu is the mean of 00:04:12.980 --> 00:04:16.360 align:start position:0% normal distribution mu is the mean of the<00:04:13.160> original<00:04:13.670> normal<00:04:14.090> distribution<00:04:15.370> Sigma 00:04:16.360 --> 00:04:16.370 align:start position:0% the original normal distribution Sigma 00:04:16.370 --> 00:04:19.240 align:start position:0% the original normal distribution Sigma the<00:04:16.910> standard<00:04:17.360> deviation<00:04:17.989> of<00:04:18.200> the<00:04:18.770> original 00:04:19.240 --> 00:04:19.250 align:start position:0% the standard deviation of the original 00:04:19.250 --> 00:04:22.630 align:start position:0% the standard deviation of the original normal<00:04:19.640> distribution<00:04:20.270> and<00:04:20.739> Z<00:04:21.739> is<00:04:22.400> the 00:04:22.630 --> 00:04:22.640 align:start position:0% normal distribution and Z is the 00:04:22.640 --> 00:04:27.030 align:start position:0% normal distribution and Z is the standardized<00:04:23.240> variable<00:04:24.080> to<00:04:24.620> be<00:04:24.770> found 00:04:27.030 --> 00:04:27.040 align:start position:0% standardized variable to be found 00:04:27.040 --> 00:04:30.450 align:start position:0% standardized variable to be found be<00:04:27.730> aware<00:04:28.230> whilst<00:04:29.230> any<00:04:29.620> normal<00:04:30.280> distribution 00:04:30.450 --> 00:04:30.460 align:start position:0% be aware whilst any normal distribution 00:04:30.460 --> 00:04:33.450 align:start position:0% be aware whilst any normal distribution can<00:04:31.270> be<00:04:31.300> transformed<00:04:32.170> using<00:04:32.740> this<00:04:32.860> formula 00:04:33.450 --> 00:04:33.460 align:start position:0% can be transformed using this formula 00:04:33.460 --> 00:04:37.140 align:start position:0% can be transformed using this formula the<00:04:34.300> formula<00:04:34.510> will<00:04:35.170> not<00:04:35.680> convert<00:04:36.340> a<00:04:36.670> skewed 00:04:37.140 --> 00:04:37.150 align:start position:0% the formula will not convert a skewed 00:04:37.150 --> 00:04:41.000 align:start position:0% the formula will not convert a skewed distribution<00:04:37.590> into<00:04:38.590> one<00:04:38.800> that<00:04:38.950> is<00:04:39.010> not<00:04:39.430> skewed 00:04:41.000 --> 00:04:41.010 align:start position:0% distribution into one that is not skewed 00:04:41.010 --> 00:04:43.650 align:start position:0% distribution into one that is not skewed so<00:04:42.010> we're<00:04:42.160> looking<00:04:42.460> at<00:04:42.580> our<00:04:42.700> theft<00:04:43.150> problem 00:04:43.650 --> 00:04:43.660 align:start position:0% so we're looking at our theft problem 00:04:43.660 --> 00:04:46.920 align:start position:0% so we're looking at our theft problem because<00:04:44.650> the<00:04:44.860> theft<00:04:45.220> data<00:04:45.690> conforms<00:04:46.690> to<00:04:46.780> a 00:04:46.920 --> 00:04:46.930 align:start position:0% because the theft data conforms to a 00:04:46.930 --> 00:04:52.510 align:start position:0% because the theft data conforms to a normal<00:04:47.590> distribution 00:04:52.510 --> 00:04:52.520 align:start position:0% 00:04:52.520 --> 00:04:55.390 align:start position:0% as<00:04:52.699> the<00:04:52.819> storm<00:04:53.060> losses<00:04:53.509> on<00:04:54.050> average<00:04:54.590> about<00:04:54.860> 200 00:04:55.390 --> 00:04:55.400 align:start position:0% as the storm losses on average about 200 00:04:55.400 --> 00:04:58.360 align:start position:0% as the storm losses on average about 200 pounds<00:04:55.729> a<00:04:55.849> day<00:04:56.440> and<00:04:57.440> we<00:04:57.560> know<00:04:57.650> the<00:04:57.860> standard 00:04:58.360 --> 00:04:58.370 align:start position:0% pounds a day and we know the standard 00:04:58.370 --> 00:05:02.550 align:start position:0% pounds a day and we know the standard deviation<00:04:59.060> of<00:04:59.180> the<00:04:59.360> daily<00:04:59.810> loss<00:04:59.990> is<00:05:00.620> 30<00:05:01.009> pounds 00:05:02.550 --> 00:05:02.560 align:start position:0% deviation of the daily loss is 30 pounds 00:05:02.560 --> 00:05:04.960 align:start position:0% deviation of the daily loss is 30 pounds now<00:05:03.560> let's<00:05:03.770> see<00:05:03.889> if<00:05:03.949> we<00:05:04.069> can<00:05:04.250> solve<00:05:04.490> a<00:05:04.789> number 00:05:04.960 --> 00:05:04.970 align:start position:0% now let's see if we can solve a number 00:05:04.970 --> 00:05:07.809 align:start position:0% now let's see if we can solve a number of<00:05:05.150> problems<00:05:05.270> for<00:05:05.960> the<00:05:06.050> store<00:05:06.259> owner<00:05:06.819> first 00:05:07.809 --> 00:05:07.819 align:start position:0% of problems for the store owner first 00:05:07.819 --> 00:05:10.420 align:start position:0% of problems for the store owner first what<00:05:08.569> are<00:05:08.660> the<00:05:08.750> chances<00:05:09.289> that<00:05:09.530> the<00:05:09.979> store<00:05:10.250> on 00:05:10.420 --> 00:05:10.430 align:start position:0% what are the chances that the store on 00:05:10.430 --> 00:05:13.180 align:start position:0% what are the chances that the store on any<00:05:10.550> given<00:05:10.880> day<00:05:11.000> will<00:05:11.479> lose<00:05:11.690> more<00:05:12.050> than<00:05:12.319> 250 00:05:13.180 --> 00:05:13.190 align:start position:0% any given day will lose more than 250 00:05:13.190 --> 00:05:18.760 align:start position:0% any given day will lose more than 250 pounds<00:05:15.520> second<00:05:16.930> what<00:05:17.930> are<00:05:18.020> the<00:05:18.080> chances<00:05:18.710> that 00:05:18.760 --> 00:05:18.770 align:start position:0% pounds second what are the chances that 00:05:18.770 --> 00:05:23.710 align:start position:0% pounds second what are the chances that the<00:05:19.190> storm<00:05:19.520> will<00:05:19.729> lose<00:05:19.970> between<00:05:21.160> 250<00:05:22.160> and<00:05:22.720> 350 00:05:23.710 --> 00:05:23.720 align:start position:0% the storm will lose between 250 and 350 00:05:23.720 --> 00:05:25.800 align:start position:0% the storm will lose between 250 and 350 pounds 00:05:25.800 --> 00:05:25.810 align:start position:0% pounds 00:05:25.810 --> 00:05:30.730 align:start position:0% pounds third<00:05:27.550> what's<00:05:28.550> the<00:05:28.759> minimum<00:05:29.270> amount<00:05:29.590> that<00:05:30.590> the 00:05:30.730 --> 00:05:30.740 align:start position:0% third what's the minimum amount that the 00:05:30.740 --> 00:05:33.610 align:start position:0% third what's the minimum amount that the store<00:05:31.039> can<00:05:31.310> expect<00:05:31.759> to<00:05:31.940> lose<00:05:32.150> the<00:05:33.050> majority<00:05:33.590> of 00:05:33.610 --> 00:05:33.620 align:start position:0% store can expect to lose the majority of 00:05:33.620 --> 00:05:38.620 align:start position:0% store can expect to lose the majority of the<00:05:33.800> time<00:05:34.039> let's<00:05:34.490> say<00:05:35.199> 95%<00:05:36.199> of<00:05:36.319> the<00:05:36.440> days<00:05:37.630> we 00:05:38.620 --> 00:05:38.630 align:start position:0% the time let's say 95% of the days we 00:05:38.630 --> 00:05:42.040 align:start position:0% the time let's say 95% of the days we want<00:05:38.810> to<00:05:38.900> know<00:05:39.020> the<00:05:39.139> probability<00:05:39.470> P<00:05:40.400> that<00:05:41.330> X<00:05:41.569> is 00:05:42.040 --> 00:05:42.050 align:start position:0% want to know the probability P that X is 00:05:42.050 --> 00:05:45.879 align:start position:0% want to know the probability P that X is greater<00:05:42.470> than<00:05:42.740> 250<00:05:43.550> pounds<00:05:44.090> and<00:05:44.409> to<00:05:45.409> find<00:05:45.710> this 00:05:45.879 --> 00:05:45.889 align:start position:0% greater than 250 pounds and to find this 00:05:45.889 --> 00:05:48.100 align:start position:0% greater than 250 pounds and to find this we'll<00:05:46.130> have<00:05:46.400> to<00:05:46.580> transform<00:05:47.360> the<00:05:47.690> normal 00:05:48.100 --> 00:05:48.110 align:start position:0% we'll have to transform the normal 00:05:48.110 --> 00:05:51.730 align:start position:0% we'll have to transform the normal distribution<00:05:49.240> into<00:05:50.240> a<00:05:50.479> standardized<00:05:51.380> normal 00:05:51.730 --> 00:05:51.740 align:start position:0% distribution into a standardized normal 00:05:51.740 --> 00:05:56.020 align:start position:0% distribution into a standardized normal distribution<00:05:52.099> and<00:05:52.819> find<00:05:53.479> the<00:05:53.599> z-score<00:05:55.030> thus 00:05:56.020 --> 00:05:56.030 align:start position:0% distribution and find the z-score thus 00:05:56.030 --> 00:05:59.830 align:start position:0% distribution and find the z-score thus we<00:05:56.240> look<00:05:56.479> for<00:05:56.690> the<00:05:56.780> probability<00:05:57.259> P<00:05:57.919> of<00:05:58.340> Z<00:05:59.120> being 00:05:59.830 --> 00:05:59.840 align:start position:0% we look for the probability P of Z being 00:05:59.840 --> 00:06:04.790 align:start position:0% we look for the probability P of Z being greater<00:05:59.990> than<00:06:00.949> X<00:06:01.340> minus<00:06:01.639> mu<00:06:02.479> over<00:06:03.289> Sigma 00:06:04.790 --> 00:06:04.800 align:start position:0% greater than X minus mu over Sigma 00:06:04.800 --> 00:06:07.999 align:start position:0% greater than X minus mu over Sigma which<00:06:05.490> is<00:06:05.639> the<00:06:05.789> probability<00:06:06.030> that<00:06:06.750> Sid<00:06:07.560> is 00:06:07.999 --> 00:06:08.009 align:start position:0% which is the probability that Sid is 00:06:08.009 --> 00:06:13.879 align:start position:0% which is the probability that Sid is greater<00:06:08.759> than<00:06:09.530> 250<00:06:11.180> -<00:06:12.180> 200<00:06:12.840> the<00:06:13.020> average<00:06:13.590> store 00:06:13.879 --> 00:06:13.889 align:start position:0% greater than 250 - 200 the average store 00:06:13.889 --> 00:06:18.309 align:start position:0% greater than 250 - 200 the average store loss<00:06:14.300> over<00:06:15.300> 30<00:06:15.659> the<00:06:16.379> standard<00:06:16.770> deviation 00:06:18.309 --> 00:06:18.319 align:start position:0% loss over 30 the standard deviation 00:06:18.319 --> 00:06:21.800 align:start position:0% loss over 30 the standard deviation which<00:06:19.319> means<00:06:19.710> we<00:06:20.460> want<00:06:20.699> the<00:06:20.909> probability<00:06:21.300> that 00:06:21.800 --> 00:06:21.810 align:start position:0% which means we want the probability that 00:06:21.810 --> 00:06:26.990 align:start position:0% which means we want the probability that Z<00:06:22.409> is<00:06:22.680> greater<00:06:23.220> than<00:06:23.490> one<00:06:24.180> point<00:06:24.210> 6<00:06:24.780> 7<00:06:25.940> now<00:06:26.940> if 00:06:26.990 --> 00:06:27.000 align:start position:0% Z is greater than one point 6 7 now if 00:06:27.000 --> 00:06:29.300 align:start position:0% Z is greater than one point 6 7 now if we<00:06:27.120> look<00:06:27.300> up<00:06:27.449> one<00:06:27.990> point<00:06:28.319> six<00:06:28.650> seven<00:06:28.919> in<00:06:29.190> our 00:06:29.300 --> 00:06:29.310 align:start position:0% we look up one point six seven in our 00:06:29.310 --> 00:06:31.850 align:start position:0% we look up one point six seven in our standardized<00:06:30.060> normal<00:06:30.360> table<00:06:31.050> we<00:06:31.080> get<00:06:31.319> a<00:06:31.379> value 00:06:31.850 --> 00:06:31.860 align:start position:0% standardized normal table we get a value 00:06:31.860 --> 00:06:37.760 align:start position:0% standardized normal table we get a value of<00:06:31.940> naught<00:06:32.940> point<00:06:33.409> naught<00:06:34.580> 475<00:06:35.930> that<00:06:36.930> is<00:06:37.080> the 00:06:37.760 --> 00:06:37.770 align:start position:0% of naught point naught 475 that is the 00:06:37.770 --> 00:06:39.950 align:start position:0% of naught point naught 475 that is the answer<00:06:38.130> is<00:06:38.250> four<00:06:39.000> point<00:06:39.330> seven<00:06:39.599> five<00:06:39.900> percent 00:06:39.950 --> 00:06:39.960 align:start position:0% answer is four point seven five percent 00:06:39.960 --> 00:06:43.520 align:start position:0% answer is four point seven five percent of<00:06:40.470> the<00:06:40.560> time<00:06:40.800> on<00:06:41.310> any<00:06:41.699> given<00:06:41.970> day<00:06:42.349> there's<00:06:43.349> are 00:06:43.520 --> 00:06:43.530 align:start position:0% of the time on any given day there's are 00:06:43.530 --> 00:06:45.439 align:start position:0% of the time on any given day there's are just<00:06:43.770> less<00:06:43.979> than<00:06:44.009> five<00:06:44.400> percent<00:06:44.430> chance<00:06:45.060> that 00:06:45.439 --> 00:06:45.449 align:start position:0% just less than five percent chance that 00:06:45.449 --> 00:06:47.870 align:start position:0% just less than five percent chance that the<00:06:45.750> store<00:06:46.199> will<00:06:46.440> lose<00:06:46.680> more<00:06:47.069> than<00:06:47.400> two 00:06:47.870 --> 00:06:47.880 align:start position:0% the store will lose more than two 00:06:47.880 --> 00:06:51.800 align:start position:0% the store will lose more than two hundred<00:06:48.000> and<00:06:48.240> fifty<00:06:48.539> pounds 00:06:51.800 --> 00:06:51.810 align:start position:0% 00:06:51.810 --> 00:06:53.690 align:start position:0% now<00:06:52.440> let's<00:06:52.650> look<00:06:52.770> at<00:06:52.890> the<00:06:53.010> possibility<00:06:53.670> that 00:06:53.690 --> 00:06:53.700 align:start position:0% now let's look at the possibility that 00:06:53.700 --> 00:06:56.840 align:start position:0% now let's look at the possibility that the<00:06:54.060> loss<00:06:54.390> in<00:06:54.750> the<00:06:54.900> day<00:06:55.140> will<00:06:56.100> be<00:06:56.310> somewhere 00:06:56.840 --> 00:06:56.850 align:start position:0% the loss in the day will be somewhere 00:06:56.850 --> 00:07:01.520 align:start position:0% the loss in the day will be somewhere between<00:06:56.960> 250<00:06:57.960> and<00:06:58.230> 350<00:06:59.040> pounds<00:07:00.290> we'll<00:07:01.290> do<00:07:01.410> this 00:07:01.520 --> 00:07:01.530 align:start position:0% between 250 and 350 pounds we'll do this 00:07:01.530 --> 00:07:05.660 align:start position:0% between 250 and 350 pounds we'll do this in<00:07:01.710> three<00:07:01.950> steps<00:07:02.270> step<00:07:03.270> one<00:07:03.920> we<00:07:04.920> know<00:07:05.190> that<00:07:05.550> the 00:07:05.660 --> 00:07:05.670 align:start position:0% in three steps step one we know that the 00:07:05.670 --> 00:07:09.200 align:start position:0% in three steps step one we know that the probability<00:07:05.970> of<00:07:06.690> more<00:07:07.650> than<00:07:08.010> 250<00:07:08.730> pounds 00:07:09.200 --> 00:07:09.210 align:start position:0% probability of more than 250 pounds 00:07:09.210 --> 00:07:13.640 align:start position:0% probability of more than 250 pounds being<00:07:09.420> lost<00:07:09.720> is<00:07:10.020> naught<00:07:10.740> point<00:07:11.190> naught<00:07:11.930> 475<00:07:12.930> we 00:07:13.640 --> 00:07:13.650 align:start position:0% being lost is naught point naught 475 we 00:07:13.650 --> 00:07:16.190 align:start position:0% being lost is naught point naught 475 we just<00:07:13.980> did<00:07:14.250> that<00:07:14.490> in<00:07:14.760> the<00:07:15.210> first<00:07:15.420> problem<00:07:15.630> so 00:07:16.190 --> 00:07:16.200 align:start position:0% just did that in the first problem so 00:07:16.200 --> 00:07:19.130 align:start position:0% just did that in the first problem so the<00:07:16.320> probability<00:07:17.040> of<00:07:17.310> a<00:07:18.210> loss<00:07:18.510> of<00:07:18.690> less<00:07:19.110> than 00:07:19.130 --> 00:07:19.140 align:start position:0% the probability of a loss of less than 00:07:19.140 --> 00:07:23.870 align:start position:0% the probability of a loss of less than 250<00:07:20.010> is<00:07:20.340> 1<00:07:21.300> minus<00:07:21.930> the<00:07:21.960> probability<00:07:22.290> that<00:07:23.250> X<00:07:23.520> is 00:07:23.870 --> 00:07:23.880 align:start position:0% 250 is 1 minus the probability that X is 00:07:23.880 --> 00:07:27.290 align:start position:0% 250 is 1 minus the probability that X is greater<00:07:24.090> than<00:07:24.360> 250<00:07:25.130> 1<00:07:26.130> minus<00:07:26.640> naught<00:07:27.030> point 00:07:27.290 --> 00:07:27.300 align:start position:0% greater than 250 1 minus naught point 00:07:27.300 --> 00:07:30.620 align:start position:0% greater than 250 1 minus naught point zero<00:07:27.660> four<00:07:27.990> seventy<00:07:28.440> five<00:07:28.700> equals<00:07:29.700> naught 00:07:30.620 --> 00:07:30.630 align:start position:0% zero four seventy five equals naught 00:07:30.630 --> 00:07:34.620 align:start position:0% zero four seventy five equals naught point<00:07:30.960> nine<00:07:31.500> five<00:07:31.800> two<00:07:32.160> five 00:07:34.620 --> 00:07:34.630 align:start position:0% 00:07:34.630 --> 00:07:38.910 align:start position:0% step<00:07:35.410> two<00:07:35.620> now<00:07:36.270> find<00:07:37.270> the<00:07:37.450> probability<00:07:38.230> of<00:07:38.500> the 00:07:38.910 --> 00:07:38.920 align:start position:0% step two now find the probability of the 00:07:38.920 --> 00:07:43.110 align:start position:0% step two now find the probability of the loss<00:07:39.130> being<00:07:39.400> more<00:07:39.880> than<00:07:40.240> 350<00:07:41.820> which<00:07:42.820> is<00:07:43.000> the 00:07:43.110 --> 00:07:43.120 align:start position:0% loss being more than 350 which is the 00:07:43.120 --> 00:07:47.750 align:start position:0% loss being more than 350 which is the probability<00:07:43.800> that<00:07:44.800> Z<00:07:45.220> is<00:07:45.520> greater<00:07:46.210> than<00:07:46.650> X 00:07:47.750 --> 00:07:47.760 align:start position:0% probability that Z is greater than X 00:07:47.760 --> 00:07:52.620 align:start position:0% probability that Z is greater than X minus<00:07:48.760> mu<00:07:49.060> over<00:07:49.570> Sigma<00:07:49.600> in<00:07:50.320> our<00:07:50.560> case<00:07:51.630> 350 00:07:52.620 --> 00:07:52.630 align:start position:0% minus mu over Sigma in our case 350 00:07:52.630 --> 00:07:56.730 align:start position:0% minus mu over Sigma in our case 350 minus<00:07:53.410> 200<00:07:54.010> over<00:07:54.220> 30<00:07:55.500> which<00:07:56.500> is<00:07:56.530> the 00:07:56.730 --> 00:07:56.740 align:start position:0% minus 200 over 30 which is the 00:07:56.740 --> 00:08:00.230 align:start position:0% minus 200 over 30 which is the probability<00:07:57.130> that<00:07:57.580> said<00:07:57.880> is<00:07:58.060> greater<00:07:58.390> than<00:07:58.630> 5 00:08:00.230 --> 00:08:00.240 align:start position:0% probability that said is greater than 5 00:08:00.240 --> 00:08:02.940 align:start position:0% probability that said is greater than 5 which<00:08:01.240> is<00:08:01.300> someone<00:08:01.840> likely<00:08:02.080> that 00:08:02.940 --> 00:08:02.950 align:start position:0% which is someone likely that 00:08:02.950 --> 00:08:09.240 align:start position:0% which is someone likely that approximates<00:08:03.760> to<00:08:03.880> 0<00:08:05.790> so<00:08:06.790> step<00:08:07.060> 3<00:08:08.250> the 00:08:09.240 --> 00:08:09.250 align:start position:0% approximates to 0 so step 3 the 00:08:09.250 --> 00:08:12.900 align:start position:0% approximates to 0 so step 3 the probability<00:08:09.720> that<00:08:10.720> X<00:08:10.990> will<00:08:11.290> lie<00:08:11.470> between<00:08:11.910> 250 00:08:12.900 --> 00:08:12.910 align:start position:0% probability that X will lie between 250 00:08:12.910 --> 00:08:14.940 align:start position:0% probability that X will lie between 250 and<00:08:12.940> 350 00:08:14.940 --> 00:08:14.950 align:start position:0% and 350 00:08:14.950 --> 00:08:20.190 align:start position:0% and 350 is<00:08:16.080> one<00:08:17.080> minus<00:08:17.830> the<00:08:18.760> probability<00:08:18.790> of<00:08:19.510> X<00:08:19.930> being 00:08:20.190 --> 00:08:20.200 align:start position:0% is one minus the probability of X being 00:08:20.200 --> 00:08:24.120 align:start position:0% is one minus the probability of X being less<00:08:20.350> than<00:08:20.830> 250<00:08:21.570> plus<00:08:22.570> the<00:08:22.800> probability<00:08:23.800> of<00:08:23.830> X 00:08:24.120 --> 00:08:24.130 align:start position:0% less than 250 plus the probability of X 00:08:24.130 --> 00:08:29.640 align:start position:0% less than 250 plus the probability of X being<00:08:24.460> more<00:08:25.240> than<00:08:25.450> 350<00:08:26.640> which<00:08:27.640> is<00:08:28.080> 1<00:08:29.080> minus 00:08:29.640 --> 00:08:29.650 align:start position:0% being more than 350 which is 1 minus 00:08:29.650 --> 00:08:34.640 align:start position:0% being more than 350 which is 1 minus naught<00:08:30.520> point<00:08:30.790> 5<00:08:31.120> 2<00:08:31.330> 5<00:08:31.650> plus<00:08:32.650> 0<00:08:33.300> which<00:08:34.300> equals 00:08:34.640 --> 00:08:34.650 align:start position:0% naught point 5 2 5 plus 0 which equals 00:08:34.650 --> 00:08:41.890 align:start position:0% naught point 5 2 5 plus 0 which equals naught<00:08:35.650> point<00:08:35.950> naught<00:08:36.540> 475 00:08:41.890 --> 00:08:41.900 align:start position:0% 00:08:41.900 --> 00:08:43.870 align:start position:0% in<00:08:42.440> this<00:08:42.560> last<00:08:42.800> problem<00:08:43.099> were<00:08:43.339> interested<00:08:43.789> in 00:08:43.870 --> 00:08:43.880 align:start position:0% in this last problem were interested in 00:08:43.880 --> 00:08:45.910 align:start position:0% in this last problem were interested in the<00:08:44.060> left<00:08:44.300> hand<00:08:44.630> tail<00:08:45.050> of<00:08:45.380> the<00:08:45.560> normal 00:08:45.910 --> 00:08:45.920 align:start position:0% the left hand tail of the normal 00:08:45.920 --> 00:08:50.620 align:start position:0% the left hand tail of the normal distribution<00:08:46.180> the<00:08:47.180> lowest<00:08:47.630> 5%<00:08:49.330> now<00:08:50.330> given 00:08:50.620 --> 00:08:50.630 align:start position:0% distribution the lowest 5% now given 00:08:50.630 --> 00:08:53.560 align:start position:0% distribution the lowest 5% now given that<00:08:50.750> a<00:08:50.839> lower<00:08:51.110> tail<00:08:51.529> value<00:08:52.100> of<00:08:52.270> minus<00:08:53.270> one 00:08:53.560 --> 00:08:53.570 align:start position:0% that a lower tail value of minus one 00:08:53.570 --> 00:08:56.829 align:start position:0% that a lower tail value of minus one point<00:08:53.870> six<00:08:54.290> five<00:08:54.560> gives<00:08:55.370> a<00:08:55.490> tail<00:08:55.730> area<00:08:56.270> of<00:08:56.510> five 00:08:56.829 --> 00:08:56.839 align:start position:0% point six five gives a tail area of five 00:08:56.839 --> 00:09:01.290 align:start position:0% point six five gives a tail area of five percent<00:08:57.380> we<00:08:58.130> have<00:08:58.810> minus<00:08:59.810> one<00:08:59.990> point<00:09:00.230> six<00:09:00.589> five 00:09:01.290 --> 00:09:01.300 align:start position:0% percent we have minus one point six five 00:09:01.300 --> 00:09:08.430 align:start position:0% percent we have minus one point six five equals<00:09:02.300> x<00:09:03.170> minus<00:09:04.100> 200<00:09:04.700> over<00:09:05.150> thirty<00:09:07.420> minus 00:09:08.430 --> 00:09:08.440 align:start position:0% equals x minus 200 over thirty minus 00:09:08.440 --> 00:09:12.370 align:start position:0% equals x minus 200 over thirty minus forty<00:09:09.440> nine<00:09:09.589> point<00:09:09.860> five<00:09:10.190> is<00:09:10.810> therefore<00:09:11.810> X 00:09:12.370 --> 00:09:12.380 align:start position:0% forty nine point five is therefore X 00:09:12.380 --> 00:09:14.870 align:start position:0% forty nine point five is therefore X minus<00:09:12.860> 200 00:09:14.870 --> 00:09:14.880 align:start position:0% minus 200 00:09:14.880 --> 00:09:19.280 align:start position:0% minus 200 x<00:09:15.270> equals<00:09:15.690> a<00:09:16.680> hundred<00:09:17.640> and<00:09:17.730> fifty<00:09:18.120> point<00:09:19.020> five 00:09:19.280 --> 00:09:19.290 align:start position:0% x equals a hundred and fifty point five 00:09:19.290 --> 00:09:23.420 align:start position:0% x equals a hundred and fifty point five oh<00:09:20.360> so<00:09:21.360> the<00:09:21.510> store<00:09:21.750> can<00:09:22.020> expect<00:09:22.440> to<00:09:22.650> lose<00:09:22.860> at 00:09:23.420 --> 00:09:23.430 align:start position:0% oh so the store can expect to lose at 00:09:23.430 --> 00:09:25.700 align:start position:0% oh so the store can expect to lose at least<00:09:23.880> a<00:09:24.150> hundred<00:09:24.600> and<00:09:24.810> fifty<00:09:25.140> pounds<00:09:25.350> and 00:09:25.700 --> 00:09:25.710 align:start position:0% least a hundred and fifty pounds and 00:09:25.710 --> 00:09:32.540 align:start position:0% least a hundred and fifty pounds and fifty<00:09:26.010> pence<00:09:26.220> on<00:09:26.600> 95<00:09:27.600> percent<00:09:27.990> of<00:09:28.080> the<00:09:28.170> days<00:09:31.550> if 00:09:32.540 --> 00:09:32.550 align:start position:0% fifty pence on 95 percent of the days if 00:09:32.550 --> 00:09:34.340 align:start position:0% fifty pence on 95 percent of the days if we<00:09:32.730> know<00:09:32.850> the<00:09:33.000> data<00:09:33.150> conforms<00:09:33.750> to<00:09:33.840> a<00:09:33.960> normal 00:09:34.340 --> 00:09:34.350 align:start position:0% we know the data conforms to a normal 00:09:34.350 --> 00:09:36.560 align:start position:0% we know the data conforms to a normal distribution<00:09:34.670> and<00:09:35.670> we<00:09:35.730> know<00:09:35.970> the<00:09:36.090> mean<00:09:36.330> and 00:09:36.560 --> 00:09:36.570 align:start position:0% distribution and we know the mean and 00:09:36.570 --> 00:09:39.350 align:start position:0% distribution and we know the mean and the<00:09:37.290> standard<00:09:37.320> deviation<00:09:37.730> we<00:09:38.730> can<00:09:38.910> derive 00:09:39.350 --> 00:09:39.360 align:start position:0% the standard deviation we can derive 00:09:39.360 --> 00:09:41.300 align:start position:0% the standard deviation we can derive considerable<00:09:40.050> volumes<00:09:40.500> of<00:09:40.680> information 00:09:41.300 --> 00:09:41.310 align:start position:0% considerable volumes of information 00:09:41.310 --> 00:09:44.780 align:start position:0% considerable volumes of information about<00:09:41.490> losses<00:09:41.850> in<00:09:42.300> libraries<00:09:43.170> or<00:09:43.470> shops<00:09:44.070> or<00:09:44.550> a 00:09:44.780 --> 00:09:44.790 align:start position:0% about losses in libraries or shops or a 00:09:44.790 --> 00:09:49.030 align:start position:0% about losses in libraries or shops or a book<00:09:45.240> store<00:09:45.540> and<00:09:45.810> so<00:09:46.200> on<00:09:46.910> but<00:09:47.910> it's<00:09:48.060> not<00:09:48.390> just 00:09:49.030 --> 00:09:49.040 align:start position:0% book store and so on but it's not just 00:09:49.040 --> 00:09:52.790 align:start position:0% book store and so on but it's not just information<00:09:50.040> about<00:09:50.130> losses<00:09:50.840> we<00:09:51.840> can<00:09:52.050> also<00:09:52.230> see 00:09:52.790 --> 00:09:52.800 align:start position:0% information about losses we can also see 00:09:52.800 --> 00:09:56.150 align:start position:0% information about losses we can also see many<00:09:53.700> other<00:09:53.850> things<00:09:54.350> the<00:09:55.350> distribution<00:09:56.040> of 00:09:56.150 --> 00:09:56.160 align:start position:0% many other things the distribution of 00:09:56.160 --> 00:09:59.030 align:start position:0% many other things the distribution of wealth<00:09:56.400> and<00:09:56.670> income<00:09:57.200> the<00:09:58.200> probability<00:09:59.010> of 00:09:59.030 --> 00:09:59.040 align:start position:0% wealth and income the probability of 00:09:59.040 --> 00:10:01.790 align:start position:0% wealth and income the probability of returns<00:09:59.610> for<00:10:00.480> some<00:10:00.690> investment<00:10:01.290> in<00:10:01.380> the<00:10:01.530> stock 00:10:01.790 --> 00:10:01.800 align:start position:0% returns for some investment in the stock 00:10:01.800 --> 00:10:04.430 align:start position:0% returns for some investment in the stock market<00:10:02.340> the<00:10:03.210> amount<00:10:03.300> of<00:10:03.630> intelligence<00:10:04.350> that 00:10:04.430 --> 00:10:04.440 align:start position:0% market the amount of intelligence that 00:10:04.440 --> 00:10:08.810 align:start position:0% market the amount of intelligence that people<00:10:04.890> have<00:10:05.070> the<00:10:05.520> list<00:10:05.790> is<00:10:06.060> endless<00:10:07.820> the 00:10:08.810 --> 00:10:08.820 align:start position:0% people have the list is endless the 00:10:08.820 --> 00:10:11.300 align:start position:0% people have the list is endless the normal<00:10:09.330> distribution<00:10:09.510> then<00:10:10.110> is<00:10:10.350> one<00:10:11.070> of<00:10:11.190> the 00:10:11.300 --> 00:10:11.310 align:start position:0% normal distribution then is one of the 00:10:11.310 --> 00:10:29.390 align:start position:0% normal distribution then is one of the most<00:10:11.550> important<00:10:12.210> concepts<00:10:12.810> its<00:10:13.380> statistics 00:10:29.390 --> 00:10:29.400 align:start position:0% 00:10:29.400 --> 00:10:31.460 align:start position:0% you