Math (Prof. Frank ONLY)

Module 1 SLP 1

I collected the data on the time it takes to cook meals each day. I have collected the data for 10 consecutive days. The independent variable in this study is the number of day and the dependent variable is the meal cooking time. Each day, I would take the reading twice; once in the morning while we cook our lunch and once in the afternoon while we (myself and my wife) cook our dinner. We shall use a stopwatch to note the times. We shall start the stopwatch at the moment we start cooking the meals and stop it the moment when we finish cooking. Each time we shall note the reading in the stopwatch. At the end of the day, we shall add up the times that we have altogether spent cooking on that particular day. This will be our data for a single day. We shall continue this process for 10 consecutive days. At the end of the experiment, we shall have 10 observations or data points.

The time spent to cook meals each day can be considered as an independent event as the time spent to cook meals on a particular day is, in general, not affected by the time spent in cooking meals on some other day. We expect the data to be normally distributed with a mean and standard deviation of meal cooking times. As with normal distributions, we expect the distribution to resemble a bell-shaped curve. Arrival of guests in the house can significantly increase the meal cooking times and this can impart positive skewness in the data distribution. Likewise, eating outs during the weekends can significantly decrease the meal cooking times and this can impart negative skewness in the data distribution.

At the end of the experiment, we shall be able to calculate the experimental probability of spending a particular time in cooking meals on a day.

We need to increase the number of days from 10 to about 30 to 35 in order for the data to provide a valid representation of the time spent in cooking meals on a day. This is because 10 data points makes too small a sample size for any valid representation. We need to increase this sample size or the number of days of collecting the data, in order to make any valid inference based on the results of the experiment.

The 10 day data collected on the time spent in cooling is in the table below. The time is in minutes and was collected for a period of 10 days.

Day	Time spent in cooking (Mins)
4/1	22
4/2	21
4/3	25
4/4	19
4/5	22
4/6	23
4/7	24
4/8	22
4/9	25
4/10	20