Due to the complex mixture of factors controlling N, together with the differences in trends recorded for particles within different size ranges, developing an air quality strategy at metro systems is a great challenge.
For example, a commonly used approach is to plot the trends in the outcome against age groups for different birth cohorts, and period effects are inferred from the differences in trends between cohorts [4].
These minor differences in trends lead to an overall weak correlation.
There were also differences in trends of resistance associated to specific animal species.
The estimates show both differences in the magnitude of changes and differences in trends due to differences in activity data.
Returning to Table 3, which considers cities separately, we notice interesting differences in trends in the black-white wage gap.
There are important regional differences in trends and seasonal patterns according to location (e.g. Arctic core vs. periphery) that are relevant to statistical analysis and forecasts.
The X ijt matrix contains individual-specific variables and household and village variables to condition the differences in trends to observable characteristics.
As mentioned above, while there is decline in Arctic sea ice overall, there are considerable regional differences in trends and seasonal ice extent.
The key challenges now are to improve the accuracy of various parameters and to reduce the differences in trends between models and observations.
To compare differences in trends in reported surgical experience of residents in obstetrics and gynecology in the United States insofar as abdominal, vaginal, and laparoscopic hysterectomy.
