## Thursday, April 8, 2010

### Chapter 16 : Data Handling Lesson 2

Dear 107s,

The job of data collection is definitely not an easy one. It requires detail planning and thinking.

Based on your experience today, I will like you to think about the following questions and post your responses under the Comment section.
1) What are some of the difficulties you have encountered today?
2) What some of things you could have done better?
3) How do you ensure that the data you collected is as accurate as possible?

#### 18 comments:

1. 1) We had difficulties counting some vehicles as many of them appeared at the same time.
2) The video and photo taking of the roads and vehicles
3) We can separate our teammates in to two groups, one counting two lanes of road and another counting the other two lanes

2. 1) The vehicles are moving and that makes it very difficult for us to count accurately.

2)I could try using other methods to record the number of vehicles passing

3)We can station the whole group together and collect data in pairs. Then after the data collection, we compare. If we have different results, we find the average.

Darius Low

3. 1. Most of the vehicles were speeding past and also there were too many lanes so I could not concentrate.

2.I could have followed the given time intervals to take pictures more closely to minimize error.

3.We could have many people working on the same thing as even though it is not that efficient, we would get a better result.

4. 1. My group leader decided that we would videotape the cars for one minute before stopping and repeating the process. However,this way many of the cars were shown in two videos, hence the results were not very accurate.
2.We could have took turns to videotaped the cars and note the same cars so that when we count the number it will be more accurate.
3. We must average the amount of cars in a minute so that the results will be more reliable.

5. 1) Many vehicles sped past us too quickly before we could count them, not to mention that a few cars were more "powerful" and faster than other cars.

2) We should have 1 person counting the vehicles one direction of the traffic while another person counts the vehicles on the opposite direction.

3) We can cross reference the information or compare the traffic condition taken by both groups in the team to confirm the traffic conditions.

6. 1. we had extreme difficulty trying to count the cars that passed by as they sped past us quite quickly
2. we could have videotaped the traffic and counted the number of cars i the video as an alternative rather than just counting out the cars that passed by as we may make a mistake
3. we can exchange information and average out the result to determine the average number of cars per minuite

7. 1) During intervals, the number of cars increased drastically and there were many to count.
2)I could have used a tripod and took a video for the whole duration so as to get a more reliable answer.
3) We can compare them with our team mates' results and see if they tally or not.

Jun Jie

8. 1) The cars travelled very fast that I could barely count it, while the busses came too slowly for my readings to be accurate.
2) I could maximize my time & take videos then go back to school to count the number of vehicles.
3) We can give a time limit, then count the number of vehicles in that time limit. Example: Take a video of 1 min. In that time, count the number of targeted vehicles.

9. 1)There were a lot of cars so some cars may be counted more than once or some cars missed out.Some of the cars were counted when they were quite a distance away from us so the result may not be accurate.
2)We could have done more planning to spread the work around and take more readings.
3)We can average out our results to get a more accurate and reliable result.

10. 1. Our timing to record the data (take photo) is not synchronized by either pairs.
2. We could have assigned a start time to start recording the data (taking photo) and from there, 3 minute intervals between each photo.
3. We have to record the data (take photo) from and of the same location per person and repeat a number of times and get an average.

11. 1) We had difficulty counting exactly how many of each type of vehicles were on the road.
2) We could have been more focused on the job.
3) The two pairs can double check their answers with each other and if the answers are the same, the data is accurate.

12. 1. There are many difficulties which I encountered during the collection of data on the bridge. These includes:
- There are many vehicles of different types coming all at once and my group lost count easily because of trying to count different vehicles at one time.
- We also lost count because there is quite some distance involved. Therefore the same vehicle we had counted would still be there for some time even after we had counted other vehicles(eg. We see a car coming in the distance and counted it. After counting another car in the distance, we down and see the same red car and mistake it for another one.)
- My group could not count all the vehicles coming at one point of time. We had to record down only type of vehicle at one time and therefore the results obtained is not accurate.
- (This is a problem for me only)At first, I planned to use the camera to take videos of the vehicles, but soon after taking for a while, I realised that my phone ran out of memory space and I ended up having to press numbers in my phone to keep track of the records. (eg. Writing 111110111110111...) This caused another problem because I had to focus on both the pressing of numbers and the counting of the vehicles.

2. I feel that we could work better in a team and maybe split ourselves up so that each of us can focus on one type of vehicle at one time. I could also have brought paper and pen for recording down as a backup. This is much more efficient as it not only reduces the time taken at each interval, it also enables us to obtain better and more accurate results

3. We can try as far as possible to put in our best effort to take videos of each part of the road, so that even if we lose count, we still have the videos as a guide for our records. We can also use these videos to double-check our work to make sure that the results are as accurate as possible. I think that all it takes is for the group to put in their best effort in trying to record the results by focusing and not getting distracted

13. 1) There were many cars and they were very fast so they were hard to count. We also forgot to bring pen and paper.

2) We could split the job-for example one guy count the left lanes and another guy count the right lanes. I could also have remembered to bring more pens.

3) We counted each vehicle twice and counted the average.

14. We had difficulties counting each subsequent vehicles that passes by the overhead bridges as it is easy to lose count and the schedule of the time of photo taken was not monitored perfectly. The vehicles is hard to be verified when they are at the end of the photo, which is eventually blurred.

We could have taken the video of the whole duration and we could have a better and precise timed interval for photos to be taken.

We can take a video of the whole duration and count the number of vehicles. We can specify what type of vehicles we are looking out for and include it in our table. By looking at the time of the event will help to determine if it is accurate. This way we would get a more specific answer and will be less likely to make mistakes.

15. 1. People were unprepared, did not bring things that they needed to bring. Therefore it was very messy.
2. We could have distributed the manpower better.
3. We tried time and time over again and when we compile the information. We can get the average.

16. 1. The cars are very fast and it is very hard to count them and sometimes when counting half-way, we lost count of the vehicles and have to start counting from the start again.

2. We could have printed out the template earlier.

3. We would take videos that are about 2.5 to 3 minutes long.

17. 1. The cars were speeding past me before we even had the chance to count them, and I often counted wrongly, counting more or less at times.
2. I could have distributed the tasks out and be more organized.
3. We would take more videos at the same time.

18. 1) What are some of the difficulties you have encountered today?
There is some kind of pattern which happens in 3 mins interval when we ere supposed to take photographs. However when we take them, there are not many vehicles. The unexpected is after we finished, there is suddenly an increase of numbers of vehicles. Must be the traffic light.
2) What some of things you could have done better?
The priority of the task ahead instead of getting distracted.
3) How do you ensure that the data you collected is as accurate as possible?
Instead of counting the number of vehicles at that particular time, for example 10 AM --> 10 cars. 10.05 AM --> 15 cars
we should take a video record it down, count the total number of vehicles and average it out to the time intervals. In that way, there is no misconception that one moment there is a lot of cars, then next no cars.